Search

Measurements of milk yield (MY), somatic cell score (SCS), percentage of fat (FP), protein (PP), lactose (LP), casein (CP) and percentage of palmitic (C16:0), stearic (C18:0), oleic (C18:1), total saturated (SFA), unsaturated (UFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids in milk from 5,224 Holstein cows were evaluated as a function of a temperature and humidity index (THI). Legendre orthogonal polynomials from second to seventh order were tested. The best fit order for MY, PP and C18:0 was the third, whereas the second for all other traits. The heritability estimates decreased for MY (0.31 to 0.14), FP (0.28 to 0.16), LP (0.43 to 0.30), SCS (0.14 to 0.09), SFA (0.33 to 0.22) and C16:0 (0.31 to 0.26), whereas increased for CP (0.32 to 0.42), MUFA (0.08 to 0.13), UFA (0.07 to 0.11) and C18:1 (0.07 to 0.11) as the THI level increased. For PP, heritabilities (0.26 to 0.39) presented larger values in intermediate THI. For PUFA and C18:0, heritabilities were approximately constant (0.13 to 0.14 and 0.15, respectively). However, the greatest variations may have been the result of the limitations of Legendre polynomials at the extreme points of the curve, and the pattern of heritabilities curves was approximately constant for the evaluated traits. Spearman's rank correlations between breeding values in extreme THI levels were greater than 0.80 for all traits considering all animals, only cows and only bulls. When considering the top 1% and the top 50% animals (only cows, only bulls and all), Spearman correlations smaller than 0.70 were found, suggesting reranking of the animals. Although there was little variation in the variance components over THI, it is possible that there is no heat stress in the animals studied, because, on average, there was no great impact of the thermal load on the traits. One possible explanation is the use of herds with little climatic difference among herds, as well as the use of fans and sprinklers into the barns. However, the THI levels may be important factors in the selection process, as reranking of animals was verified.

We conducted a study to identify the fecal metabolite profle and its proximity to the ruminal metabolism of Nelore steers based on an untargeted metabolomic approach. Twenty-six Nelore were feedlot with same diet during 105 d. Feces and rumen fuid were collected before and at slaughter, respectively. The metabolomics analysis indicated 49 common polar metabolites in the rumen and feces. Acetate, propionate, and butyrate were the most abundant polar metabolites in both bio-samples. The rumen presented signifcantly higher concentrations of the polar compounds when compared to feces (P< 0.05); even though, fecal metabolites presented an accentuated representability of the ruminal fuid metabolites. All fatty acids present in the ruminal fuid were also observed in the feces, except for C20:2n6 and C20:4n6. The identifed metabolites ofer information on the main metabolic pathways (higher impact factor and P< 0.05), as synthesis and degradation of ketone bodies; the alanine, aspartate and glutamate metabolisms, the glycine, serine; and threonine metabolism and the pyruvate metabolism. The fndings reported herein on the close relationship between the ruminal fuid and feces metabolic profles may ofer new metabolic information, in addition to facilitating the sampling for metabolism investigation in animal production and health routines. Made available in DSpace on 2021-12-13T15:00:43Z (GMT). No. of bitstreams: 1 ComparativeUntargetedMetabolome.pdf: 1971534 bytes, checksum: 04cf77d8b820aee368be3ff254d22a28 (MD5) Previous issue date: 2021

Evaluation of genetic and phenotypic trends is important to monitor the evolution of dairy cattle breeding programs. Traits that are not commonly included as selection goals should also be monitored, especially when they have some effect on consumer health, such as milk fatty acids profile. Thus, the aim was to evaluate the genetic and phenotypic trends of the milk fatty acids composition on a Holstein dairy cattle population, from three farms, reared in a tropical environment. Monthly records of palmitic (C16:0), stearic (C18:0), oleic (C18:1), total saturated (SFA), unsaturated (UFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids content in milk (g/100 g of milk), were collected of 2047 Holstein cows from three Brazilian farms between May and December of 2012. The pedigree file contained 7963 animals of seven generations. Genetic and phenotypic trends were obtained by linear regression of breeding values or phenotypic values, respectively, over generations. Single-trait analyses were performed and the breeding values were estimated using Bayesian approach. All traits showed negative phenotype trend (−0.02723 g/100 g of milk to −0.00395 g/100 g of milk), indicating reduction of the phenotypic value over generations. According to the genetic trends for MUFA and PUFA (−0.00023 and −0.00005, respectively, in g/100 g of milk) the breeding values of the animals were reduced throughout the generations, while for SFA, C16:0 and C18:0 the genetic trends (0.00134, 0.00052 and 0.00013, respectively, in g/100 g of milk) showed an increase in breeding values, possibly due to correlated effects originated from selection protocols applied to the herd. The linear regression coefficients of the genetic values in the generations were not significant for UFA and C18:1 (p-value > 0.6226 and p-value > 0.9708, respectively). Significant genetic and phenotypic trends of small magnitude were obtained, which may be a consequence of the absence of direct selection for these traits in these populations. Genetic and phenotypic gains for fatty acids profile in milk should be monitored to guide breeding programs in their selection objectives. It is suggested to investigate the causes of possible correlated response in the studied populations.

The current study was carried out to examine the effect of cottonseed processing and chitosan supplementation on lamb performance, digestibility and nitrogen digestion. Eighty uncastrated Santa Inês lambs (23 ± 2.2 kg average weight, 4 months old) were distributed in a completely randomized design in a 2 × 2 factorial arrangement that consisted of two cottonseed processing forms (whole or ground) and two chitosan levels (0 or 136 mg/kg live weight). Higher dry matter and organic matter apparent digestibility coefficient (ADC) was achieved with the diets containing the whole cottonseed. Ether extract ADC was higher in the animals fed the chitosan-containing diet. There was an interaction effect on the ADC of neutral detergent fibre corrected for ash and protein, which increased with chitosan inclusion associated with the whole cottonseed. The lambs that received the treatment containing the whole cottonseed showed higher microbial protein synthesis. Chitosan addition increased nitrogen retention. The animals fed chitosan-containing diets showed higher microbial protein synthesis. There was an interaction effect on microbial protein synthesis. Whole cottonseed associated with chitosan in lamb diets increases ether extract ADC and microbial protein synthesis.

Intake, digestibility, nitrogen (N) balance, microbial protein synthesis, weight gain, yields of the main commercial cuts and carcass morphometric measurements were evaluated in lambs fed diets containing different levels of chitosan. Sixty Santa Inês crossbred sheep with an average body weight (BW) of 24 ± 2.2 kg were assigned to three treatments (diets containing 0, 136 or 272 mg chitosan/kg BW) in a completely randomized design. There was no effect of chitosan on dry matter (DM) intake. Ingested and retained N showed a quadratic response, with the highest values estimated at the chitosan levels of 142 and 152 mg/kg BW, respectively. Similar to N balance, microbial protein synthesis showed the same quadratic response, in which the level of 136 mg/kg BW resulted in higher synthesis when compared with the other levels. No effect of chitosan was detected on average daily gain, final weight, or carcass variables (hot carcass weight, cold carcass weight, yield of commercial cuts and morphometric measurements of the carcass). Conformation, visceral fat content and fatness of carcasses were also not altered by the use of chitosan. Chitosan improves the digestibility of DM, crude protein and neutral detergent fibre, and increases N balance and microbial protein synthesis but does not change the production performance of feedlot lambs.

This study evaluated the effect of roughage:concentrate (R:C) ratio associated with a variable particle size of physically effective neutral detergent fibre (peNDF8) in the forage (Tifton-85 hay) on the performance, carcass traits and meat quality of lambs. Seventy-two 4-month-old, non-castrated Santa Ines male lambs (23.5 ± 2.32 kg BW) were distributed in a completely randomized design, in a 2 × 2 factorial arrangement [two peNDF8 hay particle sizes (13 and 6 mm) and two R:C ratios (700:300 and 500:500 g/kg DM total)]. DMI, DM, NFC and TDN digestibility's, N-intake and N-faecal excretion were affected by the R:C ratio (P < 0.05). However, the N-retained was not affected by the studied variables (P > 0.05). It was observed an interaction (P < 0.05) between the peNDF8 and R:C ratios for final BW, average daily gain (ADG), colour parameters and pH 24 h. The lower roughage ratio provided greater (P < 0.05) concentrations of C14:1, C16:1–cis9, C18:1–cis9, ΣMUFA, Σn–6:Σn–3 and hypocholesterolemic/hypercholesterolemic index, enzymatic activity Δ9desaturase-C16 and -C18. Lambs fed a lower roughage diet had improved performance and feed efficiency, however, presented reduced polyunsaturated fatty acids (PUFA) concentrations in the meat, especially Σn–3 family. Higher roughage diet and larger peNDF8 particle size improved the concentrations of PUFA while decreased Σn–6:Σn–3 ratio in meat. Larger peNDF8 particle size associated with higher roughage proportion, have reduced animal performance however, it increased protein concentration, a* and C* colour parameter without affecting fatty acids profile of Longissimus lumborum muscle.

Results of nutrient requirements as determined in dose-response trials are valid only for fish within the same size range of that of experimental model fish. This study used the factorial approach to estimate digestible energy (DE) and digestible protein (DP) requirements for maintenance and growth of pacu ( Piaractus mesopotamicus ). Juvenile pacu (63.5 ± 1.27 g) were stocked in a recirculation system (26.89 ± 0.36 °C) for 58 days, and fed two daily meals. One diet contained 6.96 % lipids (LF) and another 9.98 % lipids (HF), both diets formulated to contain 32 % crude protein, theoretical dietary energy level for maintenance (52.23 kJ DE kg−0.80 d−1), in a completely randomized, 2 × 5 factorial experimental design. The apparent digestibility coefficients of energy and protein were 84.66 ± 0.27 % and 89.20 ± 0.61 %, respectively, determined in specific assays for the HF diet, while for the LF diet, the values were 84.52 ± 0.37 % and 89.19 ± 0.16 %, respectively. The analysis of growth and carcass composition data revealed that dietary requirements of digestible energy and protein for maintenance were not influenced by dietary lipid levels; however, requirements of growth digestible energy were higher for fish fed the LF diet (1.39) than for fish fed the HF diet (1.29). The requirement of DP for growth, expressed as g of DP per g of deposited protein, were higher for fish fed the LF diet than for fish fed the HF diet (1.70 vs 1.58).

A total of 96 genetically lean immunocastrated male pigs were used in a 98-day study to evaluate the effects of including 3% soybean oil (SO), canola oil (CO), or fish oil (FO) in the diets vs. feeding a standard commercial diet with 1.5% SO (control) on growth performance, carcass and meat quality traits, consumer acceptability, and intramuscular fatty acid composition of the longissimus lumborum (LL) muscle. Pigs were blocked by initial body weight (BW; 28.44 ± 2.95 kg) and assigned to one of four treatments, with six replicate pens per treatment and four pigs per pen. Pig BW and pen feed disappearance were recorded weekly. At the conclusion of the study, pigs were slaughtered, carcass characteristics were measured, and a sample of the LL was removed for meat quality assessment, fatty acid composition analysis, and overall liking evaluation. Dietary treatments had no effect on overall growth performance and pig carcasses. Although loins from pigs fed diets containing either 3% SO or CO had decreased (P = 0.05) Warner-Bratzler shear force, only the addition of 3% SO to pig diets resulted in loin chops that were rated higher (P

This study aimed to examine the productive and metabolic parameters, carcass and meat characteristics of lambs fed sorghum silage treated with urea and Lactobacillus buchneri. Forty whole male Santa Ines lambs fed a diet with a 50:50 roughage: concentrate ratio, and randomly assigned to four groups considering roughage treatments SS - sorghum silage without additive; SSI - sorghum silage with inoculant (Lactobacillus buchneri, 105 CFU/g fresh matter); SSU - sorghum silage with urea [1% dry matter (DM)]; or SSUI - sorghum silage with urea and inoculant. The experiment was a completely randomized design with ten replicates, each animal represented an experimental unit. The intakes of DM (DMI) (P

Made available in DSpace on 2019-10-04T12:15:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-09-03 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Mineral content affects the biological processes underlying beef quality. Muscle mineral concentration depends not only on intake-outtake balance and muscle type, but also on age, environment, breed, and genetic factors. To unveil the genetic factors involved in muscle mineral concentration, we applied a pairwise differential gene expression analysis in groups of Nelore steers genetically divergent for nine different mineral concentrations. Here, based on significant expression differences between contrasting groups, we presented candidate genes for the genetic regulation of mineral concentration in muscle. Functional enrichment and protein-protein interaction network analyses were carried out to search for gene regulatory processes concerning each mineral. The core genetic regulation for all minerals studied, except Zn, seems to rest on interactions between components of the extracellular matrix. Regulation of adipogenesis-related pathways was also significant in our results. Antagonistic patterns of gene expression for fatty acid metabolism-related genes may explain the Cu and Zn antagonistic effect on fatty acid accumulation. Our results shed light on the role of these minerals on cell function. Univ Fed Sao Carlos, Dept Evolutionary Genet & Mol Biol, Sao Carlos, SP, Brazil Univ Sao Paulo, Dept Anim Sci, ESALQ, Piracicaba, Brazil Embrapa Pecuaria Sudeste, Sao Carlos, SP, Brazil Univ Sao Paulo, Phys Inst Sao Carlos, Sao Carlos, SP, Brazil Sao Paulo State Univ, Anim Sci Dept, Lab Mol Genet, Jaboticabal, Brazil Bahia Fed Inst Educ Sci & Technol, Ilheus, Brazil Univ Queensland, Fac Sci, Sch Chem & Mol Biosci, Brisbane, Qld, Australia NGS Solucoes Genom, Rua Ajudante Albano 847, Piracicaba, SP, Brazil Sao Paulo State Univ, Anim Sci Dept, Lab Mol Genet, Jaboticabal, Brazil FAPESP: 2012/23638-8

Background: The impact of extreme changes in weather patterns in the economy and humanity welfare are some of the biggest challenges that our civilization is facing. From the anthropogenic activities that contribute to climate change, reducing the impact of farming activities is a priority, since its responsible for up to 18% of greenhouse gases linked to such activities. To this end, we tested if the ruminal and fecal microbiomes components of 52 Brazilian Nelore bulls, belonging to two experimental groups based on the feed intervention, conventional (A) and byproducts based diet (B), could be used as biomarkers for methane (CH4) emission.Results: We identified a total of 5,693 Amplicon Sequence Variants (ASVs) in the Nelore bulls microbiomes from the experimental group B. Statistical analysis showed that the microbiome populations were significantly different among treatment groups. Differential abundance (DA) analysis with the ANCOM approach identified 30 bacterial and 15 archaea ASVs as DA among treatment groups. Random forest models, using either bacteria or archaea ASVs as predictors, were able to predict the treatment group with high accuracy (r2>0.85). Association analysis using Mixed Linear Models indicate that bacterial and archaea ASVs are linked to the CH4 emission phenotype, of which the most prominent were the ruminal ASV 40 and fecal ASV 35. These ASVs contributed to a 9.7% increase and 7.3% decrease of the variation in CH4 emission, respectively, which indicated their potential as targets for feed interventions and/or biomarkers.Conclusion: The feed composition induced significant differences in abundance and richness of ruminal and fecal microbial populations. The dietary treatment based on industrial byproducts applied had an impact on the microbiome diversity of bacteria and archaea, but not on protozoa. Microbiome components (ASVs) of bacteria and archaea can be successfully used to predict the treatment group, thus giving support to the hypothesis that the feed intervention modulate microbiome abundance and diversity. Microbiome components were associated with CH4 emission in both microbiomes. Therefore, both ruminal and fecal ASVs can be used as biomarkers for methane production and emission.

The objective of this study was to evaluate the effects of the association of cottonseed processing method with chitosan on carcass traits and meat quality of lambs finished in feedlot. Eighty lambs with an average body weight of 20.6 kg, with 04 months of age, were distributed in a completely randomized design, in a 2 x 2 factorial arrangement. The factors were represented by two cottonseed processing method (whole or ground) and two levels of chitosan (0 and 136 mg/kg BW). The association of cottonseed processing method with chitosan in the lamb diet did not affect (P>0.05) carcasses traits. The pH, color, cooking losses, shear force, and proximate composition of meat were also not affected (P>0.05) by the processing method of cottonseed or its association with chitosan in the lamb diets. There was an increase in palmitoleic (c9-C16:1; P = 0.01) and conjugated linoleic (P = 0.02) fatty acids when ground cottonseed was associated with chitosan. Ground cottonseed associated with chitosan increases the concentration of unsaturated fatty acids in the meat of feedlot lambs.

MicroRNAs (miRNAs) are key regulators of gene expression, potentially affecting several biological processes, whose function can be altered by sequence variation. Hence, the integration of single nucleotide polymorphisms (SNP) and miRNAs can explain individual differences in economic traits. To provide new insights into the effects of SNPs on miRNAs and their related target genes, we carried out a multi-omic analysis to identify SNPs in miRNA mature sequences (miR-SNPs) associated with fatty acid (FA) composition in the Nelore cattle. As a result, we identified 3 miR-SNPs in different miRNAs (bta-miR-2419-3p, bta-miR-193a-2, and bta-miR-1291) significantly associated with FA traits (p-value &lt, 0.02, Bonferroni corrected). Among these, the rs110817643C&gt, T, located in the seed sequence of the bta-miR-1291, was associated with different &omega, 6 FAs, polyunsaturated FA, and polyunsaturated:saturated FA ratios. Concerning the other two miR-SNPs, the rs43400521T&gt, C (located in the bta-miR-2419-3p) was associated with C12:0 and C18:1 cis-11 FA, whereas the rs516857374A&gt, G (located in the bta-miR-193a-2) was associated with C18:3 &omega, 6 and ratio of &omega, 6/&omega, 3 traits. Additionally, to identify potential biomarkers for FA composition, we described target genes affected by these miR-SNPs at the mRNA or protein level. Our multi-omics analysis outlines the effects of genetic polymorphism on miRNA, and it highlights miR-SNPs and target candidate genes that control beef fatty acid composition.

A gordura do leite é composta, predominantemente, por ácidos graxos. O leite bovino apresenta alta concentração de ácidos graxos saturados, alguns associados ao aumento do risco de doenças cardiovasculares em humanos. Porém, muitos desses, possuem efeitos neutros ou positivos sobre a saúde, assim como alguns ácidos graxos insaturados. O perfil da gordura do leite de bovinos pode ser alterado por suplementação lipídica de maneira rápida e eficiente, porém, verifica-se também variação genética nesse perfil e o melhoramento genético se torna mais relevante do que a suplementação por apresentar resultados permanentes. Esta revisão de literatura teve como objetivo reunir os principais resultados referentes aos aspectos genéticos do perfil de ácidos graxos no leite de bovinos.

Fatty acid (FA) content affects the sensorial and nutritional value of meat and plays a significant role in biological processes such as adipogenesis and immune response. It is well known that, in beef, the main FAs associated with these biological processes are oleic acid (C18:1 cis9, OA) and conjugated linoleic acid (CLA-c9t11), which may have beneficial effects on metabolic diseases such as type 2 diabetes and obesity. Here, we performed differential expression and co-expression analyses, weighted gene co-expression network analysis (WGCNA) and partial correlation with information theory (PCIT), to uncover the complex interactions between miRNAs and mRNAs expressed in skeletal muscle associated with FA content. miRNA and mRNA expression data were obtained from skeletal muscle of Nelore cattle that had extreme genomic breeding values for OA and CLA. Insulin and MAPK signaling pathways were identified by WGCNA as central pathways associated with both of these fatty acids. Co-expression network analysis identified bta-miR-33a/b, bta-miR-100, bta-miR-204, bta-miR-365-5p, btamiR-660, bta-miR-411a, bta-miR-136, bta-miR-30-5p, bta-miR-146b, bta-let-7a-5p, bta-let-7f, bta-let-7, bta-miR 339, bta-miR-10b, bta-miR 486, and the genes ACTA1 and ALDOA as potential regulators of fatty acid synthesis. This study provides evidence and insights into the molecular mechanisms and potential target genes involved in fatty acid content differences in Nelore beef cattle, revealing new candidate pathways of phenotype modulation that could positively benefit beef production and human consumption. Made available in DSpace on 2019-07-25T01:02:05Z (GMT). No. of bitstreams: 1 APCoexpressionnetworks.pdf: 1517209 bytes, checksum: c6c99bbfd9721e2c08e0d765e8b03b88 (MD5) Previous issue date: 2019 Article 651. Na publicação: Adhemar Zerlotini, Luciana C.A. Regitano.

Context Reproductive technologies may either contribute to the increase of genetic gains or inbreeding levels in dairy cattle breeding programs and herds. In general, studies have evaluated the impacts of inbreeding on traditional traits, such as production and reproduction. However, studies on novel traits, such as milk fatty acids profile, are scarce in the literature. Aim We aimed to evaluate the impact of inbreeding levels on milk fatty acids profile measured in a Brazilian Holstein cattle population. Methods Monthly records of the percentages (%) of palmitic, stearic, oleic, total saturated, unsaturated, monounsaturated and polyunsaturated fatty acids in milk were collected from 2047 Holstein cows between May and December 2012. The pedigree file contained 7963 animals over seven generations. The inbreeding trend was evaluated by linear regression of inbreeding coefficients on generations. The inbreeding impacts on breeding and phenotypic values were evaluated by linear regression of breeding values and phenotypic values on generations respectively. Breeding values were obtained by a Bayesian approach based on an animal model that included the systematic effect of contemporary group, cubic effect of days in milk as a covariate, and the random direct additive genetic and animal permanent environmental effects. Key results The average inbreeding coefficient was 0.28% for all animals, and 1.39% for inbred animals. Inbreeding tended to increase 0.24% per generation (P-value 0.18, 0.10, 0.16, 0.26, 0.51 and 0.09 respectively); whereas for polyunsaturated fatty acids, they were significant (P-value 0.33, 0.78, 0.48, 0.32 and 0.07 respectively). However, they were significant for saturated and palmitic fatty acids (P-values

Background Despite the health concerns and nutritional importance of fatty acids, there is a relative paucity of studies in the literature that report genetic or genomic parameters, especially in the case of sheep populations. To investigate the genetic architecture of fatty acid composition of sheep, we conducted genome-wide association studies (GWAS) and estimated genomic heritabilities for fatty acid profile in Longissimus dorsi muscle of 216 male sheep. Results Genomic heritability estimates for fatty acid content ranged from 0.25 to 0.46, indicating that substantial genetic variation exists for the evaluated traits. Therefore, it is possible to alter fatty acid profiles through selection. Twenty-seven genomic regions of 10 adjacent SNPs associated with fatty acids composition were identified on chromosomes 1, 2, 3, 5, 8, 12, 14, 15, 16, 17, and 18, each explaining ≥0.30% of the additive genetic variance. Twenty-three genes supporting the understanding of genetic mechanisms of fat composition in sheep were identified in these regions, such as DGAT2, TRHDE, TPH2, ME1, C6, C7, UBE3D, PARP14, and MRPS30. Conclusions Estimates of genomic heritabilities and elucidating important genomic regions can contribute to a better understanding of the genetic control of fatty acid deposition and improve the selection strategies to enhance meat quality and health attributes.

The effect of tumbling with brines on different portions of the biceps femoris muscle was evaluated for the quality of beef from cattle older than 30 mo. Six biceps femoris muscles were divided into portions: origin (OP), insertion 1(IP1), and insertion 2 (IP2). The portions were sliced into steaks and were treated with no tumbling (control), tumbling with brine (BR), and tumbling with brine and hydrolyzed soy protein (BR+HSP). The steaks were vacuum packaged and stored for 1 and 12 d and then analyzed for pH, yield, color, cooking loss, and shear force. The control steaks from the OP had higher (P < 0.05) pH and shear force values and lower (P < 0.05) L* values than the control steaks from IP2. The pH and a* and b* values increased (P < 0.05) and the L* values and cooking loss decreased (P < 0.05) when the steaks were tumbled with BR and BR+HSP. Overall, substantial variation was found for the variables among the different portions of the biceps femoris muscle. Based on the lower lightness (low exudation) and greater yellow and red intensity (less oxidation) of the meat, the tumbling with brines improved the meat quality. However, the hydrolyzed soy protein incorporated into the brine did not increase the effect compared with using the brine alone for most of the variables.

Background Lipids are a class of molecules that play an important role in cellular structure and metabolism in all cell types. In the last few decades, it has been reported that long-chain fatty acids (FAs) are involved in several biological functions from transcriptional regulation to physiological processes. Several fatty acids have been both positively and negatively implicated in different biological processes in skeletal muscle and other tissues. To gain insight into biological processes associated with fatty acid content in skeletal muscle, the aim of the present study was to identify differentially expressed genes (DEGs) and functional pathways related to gene expression regulation associated with FA content in cattle. Results Skeletal muscle transcriptome analysis of 164 Nellore steers revealed no differentially expressed genes (DEGs, FDR 10%) for samples with extreme values for linoleic acid (LA) or stearic acid (SA), and only a few DEGs for eicosapentaenoic acid (EPA, 5 DEGs), docosahexaenoic acid (DHA, 4 DEGs) and palmitic acid (PA, 123 DEGs), while large numbers of DEGs were associated with oleic acid (OA, 1134 DEGs) and conjugated linoleic acid cis9 trans11 (CLA-c9t11, 872 DEGs). Functional annotation and functional enrichment from OA DEGs identified important genes, canonical pathways and upstream regulators such as SCD, PLIN5, UCP3, CPT1, CPT1B, oxidative phosphorylation mitochondrial dysfunction, PPARGC1A, and FOXO1. Two important genes associated with lipid metabolism, gene expression and cancer were identified as DEGs between animals with high and low CLA-c9t11, specifically, epidermal growth factor receptor (EGFR) and RNPS. Conclusion Only two out of seven classes of molecules of FA studied were associated with large changes in the expression profile of skeletal muscle. OA and CLA-c9t11 content had significant effects on the expression level of genes related to important biological processes associated with oxidative phosphorylation, and cell growth, survival, and migration. These results contribute to our understanding of how some FAs modulate metabolism and may have protective health function. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3306-x) contains supplementary material, which is available to authorized users.

Knowledge on fasting heat production (HEf) of fish is key to develop bioenergetics models thus improving feeding management of farmed species. The core of knowledge on HEf of farmed, neotropical fish is scarce. This study assessed the effect of body mass and water temperature on standard metabolism and fasting heat production of pacu, Piaractus mesopotamicus, an omnivore, Neotropical fresh water characin important for farming and fisheries industries all through South American continent. An automated, intermittent flow respirometry system was used to measure standard metabolic rate (SMR) of pacu (17 - 1,050 g) at five water temperatures: 19, 23, 26, 29 and 33 °C. Mass specific SMR increased with increasing water temperature but decreased as function of body mass. The allometric exponent for scaling HEf was 0.788, and lied in the range recorded for all studied warm-water fish. The recorded van't Hoff factor (Q10) for pacu (2.06) shows the species low response to temperature increases. The model HEf = 0.04643×W0.7882×T1.837 allows to predict HEf (kJ d-1) from body mass (W, kg) and water temperature (T, °C), and can be used in bioenergetical models for the species.

The objective of this study was to identify species of yeasts in samples of high moisture corn (HMC) and corn silage (CS) collected from farms throughout the United States. Samples were plated and colonies were isolated for identification using DNA analysis. Randomly selected colonies were also identified by fatty acid methyl esters (FAME) and by physiological substrate profiling (ID 32C). For CS, Candida ethanolica, Saccharomyces bulderi, Pichia anomala, Kazachstania unispora, and Saccharomyces cerevisiae were the predominant yeasts. Pichia anomala, Issatchenkia orientalis, S. cerevisiae, and Pichia fermentans were the prevalent species in HMC. The 3 identification methods were in agreement at the species level for 16.6% of the isolates and showed no agreement for 25.7%. Agreement in species identification between ID 32C and DNA analysis, FAME and ID 32C, and FAME and DNA analysis was 41.1, 14.4, and 2.2%, respectively. Pichia anomala and I. orientalis were able to grow on lactic acid, whereas S. cerevisiae metabolized sugars (galactose, sucrose, and glucose) but failed to use lactic acid. The yeast diversity in CS and HMC varied due to type of feed and location. Differences in species assignments were seen among methods, but identification using substrate profiling generally corresponded with that based on DNA analysis. These findings provide information about the species that may be expected in silages, and this knowledge may lead to interventions that control unwanted yeasts.

The objectives of this study were to determine the effects of using different buffer sources and monensin on total tract apparent digestibility of nutrients and ruminal constituents of feedlot lambs fed high grain diets. Twenty-four lambs cannulated in the rumen were used in a randomized complete block design. Animals were fed diets containing 90% concentrate and 10% hay with addition of two limestone sources of different particle sizes and sodium bicarbonate, with or without monensin addition. Experimental treatments were arranged in a 2 × 3 factorial, with two monensin (0 or 30 mg/kg of diet) and three buffers: L = 1.3% limestone; FL = 1.3% filler limestone, and L + SB = 1.3% limestone + 1% sodium bicarbonate (DM basis). Dry matter, organic matter and crude protein digestibilities were higher (P

The aim of this work was to study the chemical composition, botanical origin and the antioxidant activity of ethanolic extracts of bee pollen. The antioxidant activity was measured by 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH•) scavenging method and β-carotene-linoleic assay. The pollen extracts were purified using a XAD2 resin and the amount of phenolic compounds and flavonoids were identified by reverse phase-high performance liquid chromatography (RP-HPLC) and gas chromatography–mass spectrometry (GC–MS) analyses. The phenolic content of bee pollen extracts before and after the resin were 38.6 and 17.8 mg/g of gallic acid equivalent in bee pollen, respectively. Two different flavonoids (rutin and myricetin) which can be accounted by the high antioxidant activity of bee pollen extracts were identified and quantified. The total antioxidant capacity measured by the DPPH• radical method increased significantly in bee pollen extracts purified with hydrophobic resin: 24.84–94.75% (Palmeira). All samples we...

Attempts to improve beef tenderness through supplementation with dietary vitamin D3 have been challenged by null results and negative impacts on animal performance and carcass traits. Because vitamin D3 is also synthesised by the animal via ultraviolet radiation from sunlight, the effectiveness of supplementation with dietary vitamin D3 may be modulated by the degree of exposure of the animal to sunlight. Hence, this work aimed to verify whether dietary vitamin D3 modifies meat quality without negatively affecting animal performance and carcass traits in B. indicus beef cattle that were either exposed to or protected from natural sunlight. Forty-two (411 ± 38 kg) Nellore-type castrated males were fed a high-concentrate diet for 45 days after assignment to a treatment group. The treatments comprised combinations of three levels of vitamin D3 [ViTD — none (V0) or 2 × 106 IU of vitamin D3 administered for either 2 (V2) or 8 (V8) consecutive days pre-slaughter] and two shading conditions (SHADE — unshaded or shaded). The post-mortem (pm) measurements were taken in the Longissimus thoracis et lumborum muscle. The animal performance and carcass traits were unaffected by ViTD or SHADE. The V2 treatment increased the Myofibrillar Fragmentation Index in shaded animals compared to unshaded ones. Animals under shade had higher muscle calcium concentration. There was no effect of either ViTD or SHADE on the shear force. The L* values were higher at 24 h pm than at 0 and 1 h pm, with no differences among the animals in the ViTD or SHADE groups. Higher a* values were observed among animals in the V8 group than in the V0 group, and higher b* values were observed among animals in the V8 group than in the V2 or V0 groups, which were not different. In conclusion, ViTD and SHADE did not affect animal performance, carcass traits or shear force, whereas animals receiving a lower ViTD dosage and SHADE exhibited altered myofibrillar fragmentation. ViTD affected the colour parameters, and changes in the lightness of the beef related to the time pm were found in meat from animals under SHADE.

Sensory analysis, instrumental color, pH, and thiobarbituric acid reactive substances (TBARS) were determined on cooked chicken meat with and without grape seed extract during refrigerated storage. The effectiveness of extracts of winery grape residue from the grape varieties ‘Isabel’ and ‘Niagara’ were tested to evaluate their effectiveness at delaying lipid oxidation in cooked chicken meat and stored under refrigeration (4±1°C). The samples were aerobically and vacuum packaged and stored for 14 days. ‘Isabel’ grape extract (IGE) and ‘Niagara’ grape extract (NGE) proved effective at promoting oxidative stability when applied at concentrations of 40 or 60 mg of gallic acid equivalents (GAE)/kg, with results similar to the synthetic antioxidant butylated hydroxytoluene (BHT). The antioxidant efficiency of the extracts was highly dependent on the concentration used. The addition of grape-residue extracts combined with vacuum packaging proved to be a good method for increasing lipid stability in cooked chicken meat stored under refrigeration.

The aim of this study was to evaluate the superovulatory (SOV) response of Sindhi (Bos indicus) donors submitted to an ovarian follicular superstimulatory protocol replacing the last two doses of pFSH by eCG. Forty-eight SOV treatments were performed in a crossover design in 19 nulliparous and primiparous females that were randomly divided into two groups: FSH (n=24), which consisted of eight pFSH injections, or FSH/eCG (n=24), which consisted of six pFSH injections followed by two eCG injections. Each female underwent two or three SOV treatments that consisted of an i.m. injection of 2mg estradiol benzoate and the insertion of an intravaginal progesterone-releasing device on Day 0. On Day 4, superstimulatory treatments were initiated and 100mg pFSH was divided into twice daily decreasing doses over a 4-day period. In the FSH/eCG group, the last two doses of pFSH were replaced by two doses of eCG (150 IU eCG each). At the time of the fifth and sixth injections of FSH, 0.150 mg PGF(2α) was injected i.m. The intravaginal progesterone-releasing device was removed at the time of the last FSH or eCG injection and ovulation was induced with 0.2 mg GnRH 18 h later. All females were artificially inseminated with frozen-thawed semen from the same bull 6 and 18 h after GnRH treatment. Seven days after GnRH treatment, embryos/ova were recovered and classified. Follicular superstimulatory (number of follicles ≥6mm at the time of the last FSH or eCG injection) and SOV (CL number) responses were determined by transrectal ultrasonography. Data were analyzed using generalized linear models and results were presented as least squares means±standard error. The FSH/eCG group had higher superstimulatory (33.8±3.9 compared to 23.8±2.6 follicles; P=0.03) and SOV (16.8±2.9 compared to 10.8±2.1 CL; P=0.10) responses. Although the number of total ova/embryos was not different between groups (8.2±1.8 compared to 5.9±1.4 for FSH/eCG and FSH groups, respectively; P=0.25), the number (5.8±1.3 compared to 2.6±0.7; P=0.02) and percentage (75.6±5.7 compared to 53.2±9.7%; P=0.05) of transferable embryos was greater for the FSH/eCG females. Therefore, there was improvement in follicular superstimulatory and SOV responses and embryo quality in FSH/eCG-treated females.

In this study, we investigated the microbial community (bacteria and protozooplankton) of a Brazilian reservoir that receives neutralized acid mine drainage flowing from piles of earth produced during uranium extraction. Thus, this research represents an attempt to fill a gap in the information on the ecology of freshwater microorganisms in tropical oligotrophic habitats, in particular in systems affected by high levels of the uranium. During the study, we observed very low chlorophyll a contents and protozooplankton cell densities and biomass. These cell densities were between 0 and 89 cells L −1 and were lower than those frequently reported for oligotrophic freshwater lakes. In contrast, bacterial densities were normal or even slightly high, between 1.85 to 6.0 × 10 9 cells L −1 . The present study has demonstrated very low protozooplankton cell densities and biomass in oligotrophic reservoir under the influence of acidic mining effuents and of high levels of ionizing radiation. It is likely that the ciliate cell densities and biomasses recorded in this study, which fall significantly below the previously published values, can be explained by the chronic fractionated exposure of these protozoa to the high levels of uranium to this system.

This study was aimed to evaluate the penetration behaviour of different brines with tumbled beef steaks from the biceps femoris muscle, specifically their interactions with pH and effects on yield. Six muscles from different animals, divided into origin (OP) and insertion (IP) portions, were cut into 60 steaks of 2.5 cm thickness and tumbled for 30 or 60 min. The steaks were tumbled with two brines, with (WTB/ HSP) or without (WTB) hydrolysed soy protein (HSP), and steaks that were not tumbled with brine or water were used as controls. Brine penetration was verified by measuring the amount of dye-containing brine (absorbance at 627 nm) recovered from homogenates of four thin (2 mm) slices from the surface of the beef steaks after tumbling. The WTB/HSP steaks exhibited greater (P < 0.05) brine penetration when tumbled for 60 min than for 30 min. The OP steaks showed greater yield and lower pH (P < 0.05) than IP steaks. HSP-added brine increased the water absorption and retention in the first slices of the steaks, and its efficiency was increased with a longer tumbling time. The portion of the biceps femoris muscle used influenced brine absorption and retention, impacting meat yield.

Objetivou-se avaliar o efeito de características físicas (densidade, solubilidade, tamanho médio de partículas e capacidade de retenção de água) sobre a fração efetivamente degradada in situ da matéria seca dos farelos de soja, canola, amendoim e algodão. Avaliou-se também a taxa de passagem de sólidos utilizando-se quatro ovinos castrados da raça Santa Inês canulados no rúmen. Amostras de 100 g de cada farelo proteico marcado com dicromato de sódio foram introduzidas no rúmen, e mantidas durante seis tempos de incubação (0, 3, 6, 12, 24 e 48 horas.) Os tempos de colheita de fezes foram de 0, 9, 12, 24, 36, 48, 72 e 96 horas. Os parâmetros de solubilidade e capacidade de retenção de água modificaram a fração efetivamente degradada. A menor densidade e a maior proporção de parede celular do farelo de canola proporcionaram menor taxa de passagem dessa fonte proteica. Somente a capacidade de retenção de água influenciou a taxa de passagem de sólidos dos ingredientes avaliados. A solubilidade, a capacidade de retenção de água, o tamanho médio de partículas e a densidade devem ser utilizados na avaliação de alimentos para estudos de degradação e cinética ruminal. A introdução de novas características físicas na biblioteca de ingredientes de sistemas de avaliação de alimentos pode auxiliar na interpretação e na predição de parâmetros metabólicos. It was aimed to evaluate in this work the effects of physical characteristics (density, solubility, average particle size and water holding capacity) on in situ effective degraded fraction of the dry matter of soybean meal, canola meal, peanut meal, and cottonseed meal. It was also evaluated the passage rate of solids using four Santa Ines castrated wethers cannulated in the rumen. Samples with 100 g of each protein meal marked with sodium dichromate were put in the rumen and kept in there during six times of incubation (0, 3, 6, 12, 24, and 48 hours). Fecal collection times were 0, 9, 12, 24, 36, 48, 72 and 96 hours. Parameters of solubility and water holding capacity changed the effectively degraded fraction. The lowest density and the highest proportion of the cellular wall of canola meal provided the lowest passage rate of this protein source. Only water holding capacity influenced solid passage rate of the evaluated ingredients. The solubility, water holding capacity, average particle size and density should be used in the diet feed evaluation for degradation and ruminal metabolism studies. Introduction of new physical characteristics in the ingredient library of food evaluation system may help to interpret and to predict metabolic parameters.

O objetivo deste estudo foi comparar a cinética de sêmen bovino criopreservado não sexado, sexado X e sexado Y antes e depois da seleção espermática por gradiente de Percoll. Amostras criopreservadas de sêmen não sexado (grupo NS) e sexado X (grupo SX) e Y (grupo SY) por citometria de fluxo, de quatro touros, foram avaliadas quanto à motilidade e à cinética espermática com o "computer-assisted semen analysis" (CASA) e o restante da amostra de cada grupo foi submetido à seleção espermática em gradiente de Percoll (45:60%). Após a seleção, foram realizadas as mesmas avaliações que antes da passagem pelo Percoll. A motilidade do grupo NS foi superior à dos grupos SX e SY e não foi observada diferença entre os grupos SX e SY nos parâmetros de cinética espermática obtidos pelo CASA, antes ou após a passagem pelo Percoll. Foi observado aumento na motilidade para todos os grupos como efeito da seleção pelo Percoll. O processo de sexagem por citometria de fluxo afeta a cinética espermática, e a passagem pelo Percoll aumenta a motilidade do sêmen sexado e não sexado sem alterar a cinética do sêmen não sexado. The objective of this study was to compare the kinetics of bovine cryopreserved nonsexed, sexed for X and sexed for Y sperm cells before and after selection using Percoll gradient. Cryopreserved nonsexed (NS group) semen samples and sexed for X (SX group) and for Y (SY group) by flow cytometry, from four different sires, were analyzed for motility by computer-assisted semen analysis (CASA), and the remainder of the sperm samples for each group was submitted to Percoll (45:60%) gradient selection. After Percoll selection, the same sperm analyses done before the passing through Percoll gradient were performed. Sperm motility was higher in the NS group than in the SX and SY groups, and no differences were observed between these last two groups for any of the sperm parameters evaluated by CASA, either before or after Percoll selection. Percoll increased motility for all groups. Changes in other characteristics evaluated by CASA were observed only in the NS group. Sex-sorting procedure by flow cytometry affected sperm kinetics, and Percoll gradient selection increases motility in sexed and nonsexed sperm without affecting the kinetics of nonsexed sperm.

Information about genetic parameters is essential for selection decisions and genetic evaluation. These estimates are population specific; however, there are few studies with dairy cattle populations reared under tropical and sub-tropical conditions. Thus, the aim was to obtain estimates of heritability and genetic correlations for milk yield and quality traits using pedigree and genomic information from a Holstein population maintained in a tropical environment. Phenotypic records (nA‚Â =A‚Â 36A‚Â 457) of 4203 cows as well as the genotypes for 57A‚Â 368 single nucleotide polymorphisms from 755 of these cows were used. Covariance components were estimated using the restricted maximum likelihood method under a mixed animal model, considering a pedigree-based relationship matrix or a combined pedigree-genomic matrix. High heritabilities (around 0.30) were estimated for lactose and protein content in milk whereas moderate values (between 0.19 and 0.26) were obtained for percentages of fat, saturated fatty acids and palmitic acid in milk. Genetic correlations ranging from -0.38 to -0.13 were determined between milk yield and composition traits. The smaller estimates compared to other similar studies can be due to poor environmental conditions, which may reduce genetic variability. These results highlight the importance in using genetic parameters estimated in the population under evaluation for selection decisions.

In order to better understand vitamin D3 in cattle metabolism, we quantified 1alpha-HYD and 24-HYD gene expression. In the kidneys of 35 male Nellore cattle, these were divided into a control group and two treatment groups (2 x 10(6) international units of vitamin D3 administered for 2 or 8 consecutive days pre-slaughter). Vitamin D3 supplementation resulted in a significant increase in 1alpha-HYD gene expression; however, significantly increased 24-HYD gene expression was only detected in cattle that had 8 days of supplementation. The finding of upregulation of 24-HYD due to vitamin D supplementation is in line with the expected rise in 24,25-di-hydroxy-vitamin D3 synthesis observed when plasma vitamin D3 concentrations are high, stimulating excretion by the organism. On the other hand, upregulation of 1alpha-HYD was unexpected, since vitamin D3 supplementation has been reported to impact these two genes in opposite directions. We conclude that vitamin D3 metabolism in these animals is more complex than previously reported.

Considering the milk fatty acid influence on human health, the aim of this study was to compare gas chromatography (GC) and Fourier transform infrared (FTIR) spectroscopy for the determination of these compounds. Fatty acid content (g/100 g of fat) were obtained by both methods and compared through Pearson’s correlation, linear Bayesian regression, and the Bland–Altman method. Despite the high correlations between the measurements ( r = 0.60–0.92), the regression coefficient values indicated higher measures for palmitic acid, oleic acid, unsaturated and monounsaturated fatty acids and lower values for stearic acid, saturated and polyunsaturated fatty acids estimated by GC in comparison to FTIR results. This inequality was confirmed in the Bland–Altman test, with an average bias varying from −8.65 to 6.91 g/100 g of fat. However, the inclusion of 94% of the samples into the concordance limits suggested that the variability of the differences between the methods was constant throughout the range of measurement. Therefore, despite the inequality between the estimates, the methods displayed the same pattern of milk fat composition, allowing similar conclusions about the milk samples under evaluation.

O objetivo deste experimento foi avaliar a qualidade nutricional de silagens de sorgo de portes alto, médio e baixo, com diferentes combinações de colmo+folhas/panícula (100:00, 80:20, 60:40, 40:60, 20:80 e 00:100), por meio de análises laboratoriais. A planta inteira foi utilizada como controle. Os híbridos foram cultivados e ensilados aos 104 dias de idade em silos de laboratório de PVC, com 10 cm de diâmetro e 40 cm de comprimento (três repetições por tratamento). Os silos foram abertos aos 56 dias após a ensilagem. Os teores de proteína bruta e a digestibilidade in vitro da matéria seca, dos fenóis totais e dos constituintes da parede celular pelo método seqüencial foram determinados. As diferenças foram verificadas por intermédio do teste SNK para fenóis totais, sendo realizada análise de regressão para os demais resultados. Os valores de carboidratos solúveis do material original foram baixos para a maioria dos tratamentos, porém isto não prejudicou a fermentação, pois houve utilização de carboidratos adicionais, como hemicelulose e celulose, durante a ensilagem, sendo a queda destes maior na panícula e em colmo+folhas, respectivamente. Os valores de fenóis totais aumentaram com a ensilagem, apesar de não ter ocorrido redução concomitante na DIVMS. A inclusão de panícula na planta reduziu os teores dos constituintes da parede celular e aumentou os valores de DIVM, indicando que uma planta de sorgo para produzir silagem de boa qualidade deve ter, no mínimo, 40% de panícula e baixos teores de lignina, fenóis totais e constituintes da fibra. The objective of this experiment was to evaluate the fermentative quality of sorghum silage of small, medium and high size with different stem+leafs/head proportions (100:00, 80:20, 60:40, 40:60, 20:80, 00:100), by means of lab analysis. The whole plant was used as control. The hybrids were cultivated and ensiled at 104 days of age in PVC lab silos measuring 10-cm of diameter by 40-cm of length (three replications per treatment). Silos were opened 56 days after the ensilage. The crude protein (CP) contents and the in vitro dry matter disappearance (IVDMD), total phenols, constituents of cell wall by sequential method. The differences were compared using SNK test for total phenols, being realized regression analysis for the other results. Original material soluble carbohydrates values were low for the majority of the treatments, but this did not prejudice the fermentation, because additional carbohydrates like hemicellulose and cellulose were used during ensilage, being the fall of these high in the heads and stem+leaves, respectively. Total phenol values increased with the ensilage, besides decrease in IVDMD did not occur, concomitantly. The heads addition to the plant reduced cell wall constituents and increased IVDMD values, indicating that, to produce good quality silage, a sorghum plant shall has, at least, 40% of heads and low lignin, tannins and cell wall constituents values.

Dietary rumen-protected fat rich in linoleic acid may affect the superovulatory response and embryo yield; however, its effects on in vivo embryo cryotolerance are unknown in zebu cattle. The present study evaluated the production and cryotolerance after freezing or vitrification of embryos from Nelore heifers supplemented with rumen-protected polyunsaturated fatty acids (PUFA). Forty heifers kept in pasture were randomly distributed into two groups according to the type of feed supplement (F, supplement with rumen-protected PUFA, predominantly linoleic; C, control fat-free supplement with additional corn). Supplements were formulated to be isocaloric and isonitrogenous. Each heifer underwent both treatments in a crossover design with 70 days between replicates. After 50 days feeding, heifers were superovulated. Embryos were evaluated morphologically and vitrified or frozen. After thawing or warming, embryo development was evaluated in vitro. There was no difference between the F and C groups (P > 0.10) in terms of embryo production. Regardless of the cryopreservation method used, Group C embryos had a greater hatching rate after 72 h in vitro culture than Group F embryos (44.3 ± 4.2% (n = 148) vs 30.9 ± 4.0% (n = 137), respectively; P = 0.04). Moreover, vitrified and frozen embryos had similar hatching rates (P > 0.10). In conclusion, dietary rumen-protected PUFA rich in linoleic acid did not improve embryo production and compromised the cryotolerance of conventionally frozen or vitrified embryos from Nelore heifers.

The objective in this experiment was to determine the effects of feeding diets with canola, sunflowerorcastor oils on intake, nutrient apparent digestibility and ruminal constituents of crossbred Dorper × Santa Ines sheep. Four rumen-cannulated animals of 90.2±11.4 kg average body weight were assigned to a 4 × 4 latin square. Animals remained individually in cages for the metabolism assay and were fed diets containing roughage at 500 g/kg and concentrate based on ground corn and soybean meal also at 500 g/kg. No oil was added to the control diet, whereas the others had canola, sunfloweror castor oils at 30 g/kg (DM basis). There was no difference for the intake of DM and nutrients, except for ether extract, which was greater when animals received oil. The digestibility coefficientsofdrymatter,organicmatter,crudeprotein,non-fiber carbohydrates and neutral detergent fiber were not changed; however, the addition of oil increased the ether extractdigestibility. The values of total digestible nutrients (TDN, g/kg of DM), digestible energy (DE, Mcal/kg of DM), TDN intake and DE intake also did not change with the addition of lipids. Concerning the ruminal constituents, the addition of vegetable oils reduced the concentrations of acetate, butyrate and total short-chain fatty acids. Adding canola, sunflowerorcastoroilsat 30 g/kg in diets with 500 g roughage/kg and 500 g concentrate/kg does not impair the intake or digestibility of nutrients in sheep, although it reduces the concentration of short-chain fatty acids in the rumen.Key Words: ammonia, lipids, metabolism, short-chain fatty acids

Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 ± 1 °C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P < 0.05) in the psychrotrophic bacterial count as from the 7th day of refrigerated storage, for the MDCM samples irradiated at the dose rate of 4.04 kGy/h. With respect to the attribute of oxidized odor, the samples irradiated with a dose rate of 0.32 kGy/h showed a stronger intensity and were significantly different (P < 0.05) from the sample irradiated with a dose rate of 4.04 kGy/h on days 0 and 2 of refrigerated storage. Irradiation with a dose rate of 4.04 kGy/h (3 kGy) was shown to be the best condition for the processing of MDCM according to the evaluation of all the variables, under the conditions of this study. Practical Application: The results obtained for the application of different dose rates of ionizing radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

Objetivou-se com este estudo avaliar os efeitos da adição de bicarbonato de sódio ou de fontes de calcário com diferentes granulometrias na ração, associadas ou não a monensina sódica, sobre o desempenho e as características de carcaça de cordeiros confinados recebendo dietas contendo alta proporção de concentrado. Quarenta e dois cordeiros Santa Inês com peso inicial de 21 ± 3 kg e 88 ± 5 dias de idade foram distribuídos em blocos completos casualizados em arranjo fatorial 2 × 3, com seis tratamentos e sete repetições. Os animais foram alimentados com rações contendo 90% de concentrado, 10% de feno de "coastcross", uma fonte de calcário (calcário calcítico ou calcário calcítico tipo filler) ou bicarbonato de sódio (NaHCO3), com ou sem adição de monensina sódica (30 mg/kg da MS). Não foi observada influência dos agentes tamponantes no consumo de matéria seca e no ganho de peso médio diário. Entretanto, a conversão alimentar dos animais alimentados com as rações contendo monensina sódica (3,32 kg MS/kg de ganho) foi melhor que naqueles que consumiram as rações sem esse aditivo (3,58 kg MS/kg de ganho). Não houve efeito dos agentes tamponantes nos parâmetros de carcaça avaliados, observando-se valores médios de 50,4%; 2,4%; 13,9 cm² e 1,9 mm para o rendimento de carcaça quente, a perda por resfriamento, a área de olho-de-lombo e a espessura de gordura, respectivamente. A adição de monensina melhora a conversão alimentar e pode aumentar a rentabilidade do sistema de produção de cordeiros confinados. The objective of this study was to assess the effects of adding sodium bicarbonate or limestone sources with different particle sizes to the diet, and their interaction with sodium monensin, on the performance and carcass characteristics of feedlot lambs fed fed high grain diets. Forty two Santa Ines lambs were used with 21 ± 3 kg initial average body weight and 88 ± 5 days old in feedlot, placed a randomized complete block design in a 2 × 3 factorial arrangement with six treatments and seven replications. Animals were fed diet containing 90% concentrate, 10% "coastcross" hay, with one source of limestone (limestone or "filler" limestone) or sodium bicarbonate (NaHCO3), with or without monensin (30 mg/kg DM). No influence was observed of the buffering agents on dry matter intake or average daily gain. However, the feed conversion of the animals fed diet containing sodium monensin (3.34 kg DM/kg gain) was better than those fed diets containing monensin (3.32 kg DM/kg gain) compared to diets without monensin (3.58 kg DM/kg gain). There was no effect of the buffering agents on the carcass characteristics assessed: the mean values were 50.4%, 2.42%, 13.9 cm² and 1.9 mm hot carcass weight, chilling losses, longissimus muscle area and fat thickness, respectively. Adding monensin to the diet improves feed conversion and may make the feedlot lambs system more profitable.

Made available in DSpace on 2021-07-14T10:28:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02. Added 1 bitstream(s) on 2021-07-14T11:31:12Z : No. of bitstreams: 1 S1516-35982009000200003.pdf: 68765 bytes, checksum: 3d48f1e5ea45295319f919948a07a32c (MD5) Objetivou-se avaliar o valor nutritivo, o perfil fermentativo e as perdas de silagens de capim-marandu submetidas aos efeitos de absorventes de umidade e aditivos. Utilizou-se o delineamento inteiramente casualizado, em arranjo fatorial 3 × 5, com três teores de matéria seca (obtidos com adição de polpa cítrica (PCP) ou casca de soja (CSP), ambas peletizadas, em comparação à ausência de aditivos) e cinco aditivos (ausência ou presença de inoculante bacteriano, benzoato de sódio ou ácido fórmico 62% ou 44%). O arranjo resultou em 15 silagens, com 4 repetições, portanto 60 silos experimentais. Avaliaram-se o valor nutritivo, as perdas por gases e efluente e a recuperação de matéria seca (MS). A adição de polpa cítrica ou casca de soja peletizada elevou os teores de MS (29,4 e 28,9%), o que reduziu a produção de efluente (4,1 e 3,8 kg/t MV) e disponibilizou substratos fermentescíveis aos microrganismos, fato confirmado pela maior capacidade fermentativa e pela digestibilidade das silagens. Os aditivos à base de ácido fórmico foram mais efetivos em preservar carboidratos solúveis e proteína, o que culminou em maior digestibilidade. Esses aditivos também reduziram as perdas por gases e elevaram a recuperação de MS. O inoculante contendo bactérias homoláticas não diferiu desses aditivos quanto à digestibilidade das silagens e ainda reduziu as perdas por gases. Entre os aditivos, o benzoato foi o menos efetivo em alterar o padrão fermentativo das silagens de capim-marandu. O valor nutritivo e as perdas da silagem com teor de umidade original, não aditivada, podem ser considerados satisfatórios, contudo, a polpa cítrica e principalmente a casca de soja peletizadas se mostraram opção interessante e devem ser mais estudadas. O uso de aditivos contendo ácido fórmico também deve ser mais explorado com gramíneas tropicais, pois promove benefícios ao longo de todo processo fermentativo. The objective of this trial was to evaluate the nutritional value, fermentation profile and dry matter losses of Palisadegrass silages ensiled with either dried citrus pulp, soybean hulls, chemical or microbial additives. The trial was carried out in a completely randomized experimental design and in a factorial arrangement (3 × 5), with three dry matter levels (wet forage or forage ensiled with pelleted citrus pulp or pelleted soybean hulls) and five additives (without or with the presence of bacterial inoculants or the addition of: sodium benzoate, formic acid in the concentration of 62% or 44%), totalizing 15 treatments and 60 experimental silos. The variables analyzed were: nutritional value, losses due to gases and effluents, and dry matter recovery. The use of dried citrus pulp or soybean hulls at the ensiling time increased the dry matter content (29.4 and 28,9%) and decreased the effluent production (4.1 and 3.8 kg/t of fresh matter), also providing fermentable substrate to microorganisms, resulting in increased fermentation coefficient and digestibility of silages. The use of formic acid resulted in silages with higher digestibility and increased water-soluble carbohydrates and crude protein content. This additive was also effective in reducing the losses due to gases and, as a result, increased the total dry matter recovery. The treatment containing homolactic bacteria showed similar trend of increasing the digestibility and reducing the losses due to gases. The use of sodium benzoate was less effective in altering the fermentation pattern of tropical silages. The nutritional value and total dry matter losses of silages ensiled without additives can be considered satisfactory. However, wet forage ensiled with dried citrus pulp and, mainly, with soybeans hulls showed the best results. Treatments containing formic acid had a beneficial effect on the fermentation profile of tropical grass silages. Universidade Estadual Paulista Universidade de São Paulo, ESALQ Universidade Estadual Paulista

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:20Z No. of bitstreams: 1 S1516-35982008000900006.pdf: 61242 bytes, checksum: 689e42b7a41b325d6e2838328d196309 (MD5) Made available in DSpace on 2013-08-22T19:07:20Z (GMT). No. of bitstreams: 1 S1516-35982008000900006.pdf: 61242 bytes, checksum: 689e42b7a41b325d6e2838328d196309 (MD5) Previous issue date: 2008-09-01 Made available in DSpace on 2013-09-30T20:11:45Z (GMT). No. of bitstreams: 2 S1516-35982008000900006.pdf: 61242 bytes, checksum: 689e42b7a41b325d6e2838328d196309 (MD5) S1516-35982008000900006.pdf.txt: 46998 bytes, checksum: 7e9b9c2f711fd5fbe20e67b798ac99f1 (MD5) Previous issue date: 2008-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:18:14Z No. of bitstreams: 2 S1516-35982008000900006.pdf: 61242 bytes, checksum: 689e42b7a41b325d6e2838328d196309 (MD5) S1516-35982008000900006.pdf.txt: 46998 bytes, checksum: 7e9b9c2f711fd5fbe20e67b798ac99f1 (MD5) Made available in DSpace on 2014-05-20T15:18:14Z (GMT). No. of bitstreams: 2 S1516-35982008000900006.pdf: 61242 bytes, checksum: 689e42b7a41b325d6e2838328d196309 (MD5) S1516-35982008000900006.pdf.txt: 46998 bytes, checksum: 7e9b9c2f711fd5fbe20e67b798ac99f1 (MD5) Previous issue date: 2008-09-01 Avaliou-se o efeito do uso de aditivos químicos nas perdas de matéria seca, no perfil fermentativo e no valor nutritivo de silagens de cana-de-açúcar. O experimento foi realizado em delineamento inteiramente casualizado com quatro repetições por tratamento (sete tratamentos). Os seguintes aditivos foram utilizados na confecção das silagens: controle (sem aditivo), L. buchneri, óxido e carbonato de cálcio em doses de 1,0 e 1,5% da massa verde e sulfato de cálcio a 1,0% da massa verde, diluídos em 40 litros de água por tonelada de forragem. As variáveis analisadas foram: perdas totais e gasosas, produção de efluente, recuperação de matéria seca, composição química e valor nutritivo. As menores perdas fermentativas e gasosas foram observadas nas silagens com óxido ou carbonato de cálcio, que resultaram em maior taxa de recuperação de matéria seca. da mesma forma, as silagens tratadas com estes aditivos apresentaram maior teor de carboidratos solúveis residuais e de ácido lático e reduzida fermentação alcoólica. As silagens tratadas com óxido e carbonato apresentaram, no momento da abertura, maior teor de cinzas, menor concentração de componentes fibrosos e maiores coeficientes digestibilidade da matéria seca e da matéria orgânica. O teor de proteína encontrado nessas silagens foi semelhante ao observado na forragem fresca. A ensilagem de cana-de-açúcar com L. buchneri e sulfato de cálcio possibilitou a obtenção de desempenho similar ao determinado com a silagem sem aditivos. Silagens tratadas com carbonato e óxido de cálcio apresentam maior desempenho durante o processo fermentativo. The objective of this trial was to evaluate the effects of chemical additives in the dry matter losses, fermentation profile, and nutritive value of sugar cane silages. The trial was carried out in a completely randomized experimental design with four replicates per treatment. The following additives were applied to the fresh forage during the ensiling: control (without additive), L. buchneri, calcium oxide and calcium carbonate,1.0 and 1.5% (wet basis) each, and calcium sulfate 1.0% (wet basis), all of them diluted in to 40 L of water per ton of fresh forage. The variables analyzed were: total and gaseous dry matter losses, dry matter recovery, fermentation end products, and nutritive value. The use of calcium oxide or calcium carbonate were effective in reducing dry matter losses and gaseous production and had the highest dry matter recovery rate. Both silages had also low ethanol content and, as a result, had greater concentrations of residual water soluble carbohydrates and lactic acid. The addition of calcium oxide and calcium carbonate at the time of ensiling produced silages with higher nutritive value compared with all other treatments, due to the increase of ash content and dry matter and organic digestibility and also, by reducing the fiber content. The crude protein content range was similar to the values observed in the fresh forage. The treatments with L. buchneri and calcium sulfate were ineffective in altering the fermentation process of sugar cane silages and became similar to the control silages. In summary, the overall analysis pointed out that the treatment containing calcium oxide and calcium carbonate improved the fermentation and storage process. USP ESALQ USP ESALQ Departamento de Zootecnia USP ESALQ Departamento de Ciências Exatas Unesp Unesp

The objectives of this study were the in situ dry degradability (ISD) determination of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF) of fresh (FSC) or ensiled sugar cane (SCS), as well as corn silage (CS), under different ruminal conditions. Two Holstein cows fitted with ruminal canulas were utilized (live weight of 450 kg) and fed diets formulated to obtain different ruminal conditions by the inclusion of two forage sources: FSC or SCS. The ISD nutrients were evaluated by the use of 20 x 40 cm nylon bags, with 50 µm porosity, being the different forages incubated in natura at 0, 12, 24, 48, 72 and 96 hours. Treatments consisted of a 3 x 2 hierarchy design (3 forages x 2 ruminal conditions). Rumen fluid samples were taken for the evaluation of rumen pH and ammonia-N. Sampling time significantly affected ruminal pH (p < 0.05). Differences were observed (p < 0.05) for the soluble fraction (a), potentially degradable fraction, undegradable fraction and potential degradability of the DM of the forages. As for degradation of NDF and ADF of forages incubated under different ruminal conditions, differences (p < 0.05) were observed only for the “a” fraction. The ruminal condition resulting from ensiled sugar cane was favorable for the degradability of the evaluated forages.

O estudo foi realizado para avaliar o efeito da estação do ano, do teor de matéria seca (MS) e da inoculação bacteriana sobre o valor nutritivo de silagens de Brachiaria brizantha cv. Marandu. O delineamento experimental foi o inteiramente casualizado, disposto em arranjo fatorial (2 × 3 × 3), com duas estações do ano (verão e inverno), três teores de MS (com ou sem emurchecimento ou adição de polpa cítrica peletizada, PCP) e ausência ou presença de inoculante (Lactobacillus plantarum ou Lactobacillus buchneri), perfazendo 18 tratamentos, cada um com quatro repetições. As silagens foram confeccionadas em baldes de plástico de 20 L. Após 90 dias do fechamento, os silos foram abertos para as avaliações. O emurchecimento elevou os teores de matéria seca (MS), fibra em detergente neutro (FDN) e lignina (LIG) em ambas as estações, porém não alterou o coeficiente de digestibilidade verdadeira in vitro da MS (DVIVMS) das silagens. A adição de PCP aumentou os teores de proteína bruta (PB) e carboidratos solúveis (CHO) e reduziu os teores de FDN, o que resultou em silagens com maior DVIVMS em ambas as estações. A inoculação não alterou a fração fibrosa e não aumentou a DVIVMS das silagens. As silagens de verão apresentaram maiores teores de PB e menores constituintes da parede celular, com exceção da hemicelulose (HEMI), o que resultou no maior coeficiente médio de DVIVMS dessas silagens. O baixo valor nutritivo das silagens de inverno contraria os resultados descritos na literatura, principalmente em virtude da maior idade de rebrotação do capim-marandu nesta estação. Desta forma, silagens de verão podem ser recomendadas como volumoso suplementar, principalmente quando acrescidas de PCP.

Objetivou-se avaliar a produção de massa seca das folhas, a relação folha/colmo e alguns índices de crescimento do capim-xaraés submetido a doses de nitrogênio (N) e potássio (K). O experimento foi conduzido em casa-de-vegetação no período de novembro/2004 a fevereiro/2005. Adotou-se esquema fatorial 4 ´ 3, perfazendo 12 combinações, as quais foram distribuídas em delineamento experimental inteiramente casualizado, com quatro repetições, perfazendo um total 48 unidades experimentais. Foram utilizadas quatro doses de N (0, 75, 150 e 225 mg dm-3) e três doses de K (0, 50 e 100 mg dm-3). Verificou-se efeito das doses de N na produção de massa seca das folhas e na produção de massa seca total, em todos os cortes, com maior produção nas doses mais elevadas de N, ao passo que o K influenciou essas variáveis apenas no segundo corte. A relação folha/colmo, a RAF, a AFE e a RPF somente foram significativas no terceiro corte da planta. Os efeitos das doses de foram decrescentes sobre essas variáveis, enquanto as doses de K agiram de modo antagônico às doses de N sobre a RAF e AFE. This work aimed to evaluate dry matter production, leaf/stem ratio and growth indexes of palisade grass cv. Xaraés grown under increasing nitrogen and potassium rates. The experiment was carried out in a greenhouse from November, 2004 until February, 2005. The experimental treatments consisted of a 4 ´ 3 factorial arrangement between nitrogen and potassium rates respectively. Nitrogen rates were 0, 75, 150, and 225 mg dm-3, whereas potassium rates were 0; 50 and 100 mg dm-3. The experiment design was completely randomized with four replications. It was verified a positive N fertilization effect both on leaf dry matter yield and total dry matter yield. Potassium influenced these same response variables only at the second harvest. The leaf/stem ratio, leaf area ratio (LAR), specific leaf area (SLA) and, leaf weight ratio (LWR) were affected by treatments only at the third harvest. Increasing N rates reduced these response variables (L/S, LAR, SLA, LWR) while potassium rates behaved in an antagonistic way on LAR and SLA.

The contents of total phenolics, flavonoids, and antioxidant activity of bee pollen ethanolic extract were determined and compared to those of commercial antioxidants. Bee pollen extract from the state of Rio Grande do Sul presented antioxidant activity statistically equal to that of α -tocopherol and higher than those of BHT and BHA. A statistically significant correlation was observed between the antioxidant activity and the total phenolics and total flavonoids contents of bee pollen extracts. HPLC technique made the identification of high contents of rutin and myricetin possible, which may partially explain the high antioxidant activity of Brazilian bee pollen.

Acute heat stress (AHS) modifies the structure of myofibrils affecting functional properties of meat, mainly the water holding capacity. This experiment aimed to identify changes in proteolysis and migration between the myofibrillar and sarcoplasmatic fractions due to pre-slaughter AHS. Myofibrillar fragmentation index (MFI), SDS-PAGE, western blot of vinculin (WB) and shear force (SF) were determined. Six hundred broilers (Gallus gallus) were slaughtered in three different days (ST). In each ST, groups of ten animals were placed in transport crates and submitted to AHS (35ºC, 75 - 85% RH) for 2 hours. Simultaneously, the non-stressed broilers (NS) were kept in thermoneutral environment (22ºC, 83 ± 6.6% RH) within the crates in the same density. After slaughter, the breast muscles were kept refrigerated until the withdrawal of all samples (0, 1, 2, 6 and 24 hours after slaughter). Sampling within AHS and NS birds was collected according to lightness value (normal L* < 49, and high > 51), except for determination of MFI and SF. The lightness was used later to perform SDS-PAGE and WB analyses. MFI kinetics showed that the fragmentation rate was superior in animals NS, indicating that AHS can harm proteolysis and rate of myofibrillar fragmentation. However, the extent of fragmentation did not change, as well as SF values. SDS-PAGE for Troponin fragments indicated a differentiated pattern between AHS and NS. The WB did not show alterations in vinculin fragmentation. Modifications in sarcoplasmatic fraction are observed in meat with high L*values, independent of environmental condition. O estresse térmico agudo (ET) causa alterações na estrutura das miofibrilas, afetando propriedades funcionais da carne, principalmente a capacidade de retenção de água. Identificaram-se mudanças na proteólise e migração entre as frações miofibrilar e sarcoplasmática, decorrentes do ET pré-abate, através do índice de fragmentação miofibrilar (MFI), SDS-PAGE para troponina (SDS), imunodetecção de vinculina (IV) e força de cisalhamento (FC). Seiscentos frangos (Gallus gallus) foram abatidos em três dias diferentes (DA). Em cada DA os animais foram colocados em caixas de transporte (10 aves/caixa) e submetidos a ET (35ºC, 75 - 85% UR)por 2 horas. Simultaneamente, o outro grupo de animais (NET) foi mantido em caixas em condição termoneutra (22ºC, 83 ± 6,6% UR) pelo mesmo período de tempo. Após o abate o músculo do peito foi coletado e mantido refrigerado, até a retirada de todas as amostras (0, 1, 2, 6 e 24 horas pós-abate). O valor de luminosidade (L* < 49, normal e > 51, alto), foi o parâmetro utilizado na amostragem para SDS e IV. A cinética do MFI demonstrou que a taxa de fragmentação foi superior nos animais NET, indicando que o estresse térmico pode prejudicar o processo de proteólise. Entretanto, a extensão da fragmentação não variou, bem como os valores de FC. No SDS ocorreram padrões diferenciados de fragmentação entre aves ET e NET. Modificações na fração sarcoplasmática foram observadas em amostras com L*, independentemente da condição ambiental.

Ensiling of sugar cane maycontribute to improve operational efficiency at farm level. However, the high ethanol levelfound in sugar cane ensiled without additive may reduce voluntary feed intake and mayaffect animal performance. This experiment was performed to evaluate the effects of freshsugar cane and sugar cane silage treated with microbial ( Lactobacillus buchneri ) or chemical(urea) additives on apparent digestibility of diets fed to lambs. Twelve Santa Ines lambs (49 ± 3 kg) were assigned to a complete randomized block design and fed a 50:50 (concentrate:roughage ratio) TMR. Experimental treatments were the roughage source: fresh sugar cane(FSC), sugar cane silage with L. buchneri (SCS + Lb), sugar cane silage with 1% urea (SCS1%) or sugar cane silage with 1.5% urea (SCS1.5%). NDF digestibility coefficient waslower (p 0.05) in nitrogen balance for all thecomparisons evaluated. The sugar cane ensiled improve NDF digestibility.

Testosterone metabolism occurs primarily in the liver, and circulating concentrations can be influenced by the amount and type of diet provided. Furthermore, there are reports of the influence of circadian rhythms on secretion of testosterone in ruminants. Based on evidence that supplementation with rumen-protected fat may increase circulating concentrations of steroid hormones (Guardieiro et al. 2010 Pesq. Agrop. Bras. 45, 408–414), this study aimed to evaluate the effect of the addition of rumen-protected fat, antioxidants, or both to the diet on serum testosterone concentration in bulls, and to assess whether there is variation in hormone concentrations at different times of the day after feeding. Forty-eight Nelore bulls were confined and assigned to four treatment groups according to the addition of rumen-protected fat, antioxidants, or both to the standard diet (sugarcane bagasse, citrus pulp, corn gluten meal, urea, and mineral salt): F) rumen-protected polyunsaturated fatty acids [PUFA; rich in linoleic, Megalac E®, QGN-Arm & Hammer, Rio de Janeiro, Brazil; 1.5% on dry matter (DM); n = 12]; A) antioxidant (a source of vitamin C and selenium, EconomasE®, Alltech Biotechnology, Buenos Aires, Argentina; 3 g/head/d; n = 12); FA) Megalac E® and EconomasE® (n = 12), or C) nothing (Control group; n = 12). After 75 days of offering diets, jugular blood samples were collected just before IV injections that were performed three times a day (7:00, 13:00, and 19:00 h) with saline (Control group, n = 24) or gonadotropin-releasing hormone (GnRH; 50 μg Gonadorelin, Fertagyl, MSD Saúde Animal, São Paulo, Brazil; GnRH group, n = 48) and 2 h afterward. Bulls were fed 1 h after the first IV GnRH/saline and the diets remained in the bunk for 17 h. Serum testosterone concentrations were measured by radioimmunoassay. Data were analysed by repeated-measures of GLIMMIX of SAS (SAS Institute Inc., Cary, NC, USA). As expected, the GnRH injections increased concentrations of testosterone after 2 h compared to saline (5.4 ± 0.16 v. 3.2 ± 0.16 ng mL–1; P