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A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to -18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (O/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

Roasted piglet (Porcheddu) is one of the most appreciated traditional Sardinian dishes obtained from suckling animals slaughtered at 8-12 kg of body weight (BW). The traditional cooking method is timeconsuming; this dish is eaten only when there is enough time for its preparation (cooking time of about 2 h). The Porcheddu is appreciated by both local and foreign consumers and there is also an increasing interest, for this traditional dish, by extra regional consumers and markets. Actually, since the occurrence of African swine fever (ASF), the trade of pigs and pig meat products is not permitted from Sardinia. The Council Directive 2002/99/EC provided a derogation for states member to authorize the production, processing and distribution of products of animal origin when a Heat treatment at a minimum temperature of 80°C, which must be reached throughout the meat is applied. The overall framework of this study was to evaluate an innovative process to obtain a traditional dish the Porcheddu suitable to achieve extra-regional markets and meet the demand of modern consumers and to assess the effect of carcass weight on the processing yield of suckling piglets, thermally treated, to obtain a ready-to-eat roast dish. [ABSTRACT FROM AUTHOR]

The feedstuffs used in dairy animals must be able to give consumers confidence about the wholesomeness of milk with regard to aflatoxin contamination. The aim of this study was to determine the excretion patterns of aflatoxin M1 (AFM1) in the milk of dairy goats fed a single dose of pure aflatoxin B1 (AFB1), which can occasionally occur if feeds are infected by hot-spot growth of molds that produce aflatoxins. Five dairy goats in midlactation were administered 0.8 mg of AFB1 orally. Individual milk samples were collected for 84 h after AFB1 dosage. Aflatoxin M1 was found in milk in the highest concentration. In all goats, AFM1 was not detected in milk before AFB1 administration, but was detected in the first milking following AFB1 administration. The excretion pattern of AFM1 concentration in milk was very similar in all goats even if the values of the concentration differed between animals. The peak values for AFM1 concentration in milk was observed in milk collected during the milking at 3 and 6 h. After the peak, the AFM1 in milk disappeared with a trend that fitted well a monoexponential decreasing function, and the toxin was not detected after 84 h. Only about 0.17% of the amount of AFB1 administered was detected as AFM1 in milk, and about 50% of this was excreted in the first liter of milk yielded after AFB1 intake. Correct procedures to prevent growth of molds, and consequent AFB1 contamination, on the feedstuffs for lactating goats represent the key to providing consumers a guarantee that milk is not contaminated by AFM1. [ABSTRACT FROM AUTHOR]

Dairy products offer an important source of iodine for humans, particularly infants and children. An adequate iodine content in the diet of lactating animals must guarantee a suitable milk iodine concentration. In this experiment, the effects of iodine supplementation of dairy goat diets on the iodine concentration, milk yield, and milk composition of goat milk were studied. Thirty crossbred dairy goats of the Sarda population were divided into 3 groups supplemented with 0 (control group), 0.45 (group 1), or 0.90 (group 2) mg of KI/d per goat. The dose of KI (76.5% of iodine) was dissolved in water and orally administered with a syringe every day for 10 wk. Mean milk iodine concentrations were 60.1 ± 50.5, 78.8 ± 55.4, and 130.2 ± 62.0 μg/L (mean ± SD) in the control group, group 1, and group 2, respectively. The extent of iodine enrichment in milk was approximately 31% in group 1 and 117% in group 2 compared with the control group. Milk yield was not influenced by KI supplementation and averaged 1,229, 1,227, and 1,179 g/d in groups 0, 1, and 2, respectively. Milk urea nitrogen concentration was significantly lower in the KI-supplemented groups (32 and 33 mg/dL in groups 1 and 2, respectively) than in the control group (37 mg/dL). Iodine supplementation of dairy goat diets can increase milk iodine content without adverse effects on milk production traits. [ABSTRACT FROM AUTHOR]

An experiment was carried out to investigate 1) the transfer of aflatoxin M1 (AFM1) into the milk of dairy ewes fed diets naturally contaminated with aflatoxin B1 (AFB1); 2) the effect of the addition of dried yeast culture in the diet on this transfer; and 3) the alteration of enzymatic activities in the liver of ewes fed diets contaminated with AFB1. Twenty-four Sarda dairy ewes were divided in 4 groups and fed a concentrate mix containing 4 amounts of wheat meal naturally contaminated with aflatoxins. The diet of the control group had no wheat meal, whereas that of treated groups had low, medium, or high amounts of contaminated wheat, which corresponded to 1.13, 2.30, and 5.03 μg of AFB1/kg of feed, respectively. The experiment lasted 14 d. On d 8 to 14 from the beginning of the trial, 12 g/d of a commercial dried yeast product (DYP) of Kluyveromyces lactis was added to the diet of each ewe. The AFM1 concentration in individual milk samples and the blood serum metabolites were measured periodically. The presence of AFM1 was first detected in milk on d 1 of administration, and then its concentration increased and approached a steady-state condition on d 3 simultaneously in all treated groups. The AFM1 in milk at the steady-state condition, which was linearly related to the AFB1 intake, was 39.72, 50.38, and 79.29 ng/L in the low-aflatoxin, medium-aflatoxin, and high-aflatoxin groups, respectively. The AFM1 concentration in milk of the high-aflatoxin group was approximately 1.5-fold greater than the European Commission maximum tolerance level (50 ng/kg). The addition of DYP to the diet did not affect the AFM1 concentration in milk. After the withdrawal of the contaminated concentrate mix, the AFM1 mean concentrations decreased quickly and were no longer detected after 3 d in all treated groups. Daily milk yield and composition did not differ because of aflatoxin treatment. Blood serum parameters (creatinine, glutamic oxalacetic transaminase, glutamic pyruvic transaminase, gamma glutamyl transferase, alkaline phosphatase, lactate dehydrogenase, cholesterol, protein, urea, calcium, and phosphorus) were not influenced by AFB1 intake. Therefore, the effect of DYP on certain blood parameters (gamma glutamyl transferase, urea, creatinine, and calcium) could not be attributed to amelioration of the aflatoxin-contaminated diet. In conclusion, diet contamination by AFB1 near the European Union tolerance level (0.005 mg/kg) in complete feed for dairy animals (e.g., high-aflatoxin group) can result in an AFM1 milk concentration higher than the European Commission maximum tolerance level. Transfer of aflatoxin from feed to milk was not affected by dietary addition of a commercial DYP. [ABSTRACT FROM AUTHOR]

The aim of this research was to determine the effect of adding extruded linseed cake to the dry diet of goats on the concentrations of conjugated linoleic acid (CLA) and vaccenic acid (VA) in milk fat. Thirty crossbreed dairy goats were divided into 3 groups. Their diet was supplemented with 0% (control group), 5% (low group), or 10% (high group) of extruded linseed cake (ELC), which supplied 0, 16, and 32 g/d of linseed fat, respectively. The milk fat percentage (overall mean 3.5%) and yield did not differ with the different diets, but fatty acid composition was affected by the ELC supplements. The inclusion of ELC in the diets did not influence the concentration of fatty acids from C6:0 to C12:0. The concentrations of C14:0 and C16:0 decreased as the quantity of ELC supplements increased. The concentrations (mg/100 mg of total fatty acid methyl esters) of VA (0.70, 1.23, and 1.39 in control, low, and high groups respectively) and cis-9,trans-11 CLA (0.63, 0.96, and 1.05 in control, low, and high groups, respectively) were increased by ELC supplements. The milk fat content of VA and cis- 9,trans-11 CLA were closely correlated (R² = 0.82). Desaturation of VA in the mammary gland to produce cis-9,trans-11 CLA was higher in the control group than in the groups with ELC diets. Extruded linseed cake supplementation to lactating goats may enhance the nutritional profile of milk lipids. [ABSTRACT FROM AUTHOR]

An experiment was carried out using dairy ewes to study the transfer of aflatoxin B1 (AFB1) from feed to milk and from milk to cheese. The effects of AFB1 on liver function and hematological parameters were also investigated. Fifteen ewes were assigned to treatments in replicated 3 x 3 Latin squares. The experimental groups received 32, 64, or 128 µg/d of pure AFB1 for 7 d followed by 5 d of clearance. On the sixth day of the first period, the total daily milk produced by each ewe was collected separately and processed into cheese. The results indicate that the level of AFB1 used did not adversely affect animal health and milk production traits. The aflatoxin M1 (AFM1) concentrations in milk approached a steady-state condition in all treated groups between 2 and 7 d after the start of treatment. The mean AFM1 concentrations of treated groups in steady-state condition (184.4, 324.7, and 596.9 ng/kg in ewes fed 32, 64, or 128 µg of AFB1, respectively) were significantly affected by the AFB1 doses. The AFM1 concentration was linearly related to the AFB1 intake/ kg of BW. The carry-over values of AFB 1 from feed into AFM1 in milk (0.26 to 0.33%) were not influenced by the AFB1 doses. The AFM1 concentrations in curd and whey were linearly related to the AFM1 concentrations in the unprocessed milk. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the amount of aflatoxin M2 in milk after feeding aflatoxin B1 to lactating dairy ewes. Materials and methods; Results and discussion; Conclusions.

The organic carbon of biosolids from civil wastewater treatment plants binds persistent organic pollutants (POPs), such as polychlorodibenzo -dioxins and -furans (PCDD/Fs), dioxin and non-dioxin -like polychlorobiphenyls (DL and NDL-PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorooctane sulfonic acid (PFOS). The use of such biosolids, derived digestates and composts as top soil improvers (TSIs) may transfer POPs into the food chain. We evaluated the potential carry-over of main bioavailable congeners from amended soil-to-milk of extensive farmed sheep. Such estimates were compared with regulatory limits (food security) and human intakes (food safety). The prediction model was based on farming practices, flocks soil intake, POPs toxicokinetics, and dairy products intake in children, of the Mediterranean area. TSI contamination ranged between 0.20–113 ng WHO-TEQ/kg dry matter for PCDD/Fs and DL-PCBs (N = 56), 3.40–616 μg/kg for ∑ 6 NDL-PCBs (N = 38), 0.06–17.2 and 0.12–22.3 μg/kg for BDE no. 47 and no. 99, 0.872–89.50 μg/kg for PFOS (N = 27). For a 360 g/head/day soil intake of a sheep with an average milk yield of 2.0 kg at 6.5% of fat percentage, estimated soil quality standards supporting milk safety and security were 0.75 and 4.0 ng WHO-TEQ/kg for PCDD/Fs and DL-PCBs, and 3.75 and 29.2 μg/kg for ∑ 6 NDL-PCBs, respectively. The possibility to use low-contaminated TSIs to maximize agriculture benefits and if the case, to progressively mitigate highly contaminated soils is discussed. [ABSTRACT FROM AUTHOR]

Grape seed is a by-product of the winery and distillery industry which could be used in animal nutrition. To test the hypothesis that dietary supplementation with this by-product can decrease the biohydrogenation (BH) of healthy fatty acids (FA), the present study evaluated the effects of grape seed supplementation, alone or combined with linseed, on ruminal BH processes in dairy sheep. In this 60-d trial, 24 lactating Sarda dairy ewes were assigned to four homogeneous groups and fed as follows: (1) control diet (CON), (2) a diet supplemented with 300 g/d per head of grape seed (GS), (3) a diet supplemented with 220 g/d per head of extruded linseed (LIN), (4) and a diet supplemented with a mix of both grape seed and linseed (300 and 220 g/d per head, respectively) (MIX). Ammonia, pH, volatile fatty acids (VFA) and FA composition were determined in rumen liquor at three sampling dates (20, 40 and 60 d). Rumen pH was not influenced by diet (P>0.05). The ammonia content was increased (P<0.05) in GS and MIX compared with LIN and CON. The molar proportions of acetate and propionate and their ratio were not affected by the diet (P>0.05), whereas the molar proportion of butyrate was the lowest in MIX. Rumenic acid (RA; CLA cis- 9, trans- 11) concentration increased in GS compared with CON (0.78 vs. 0.45 mg/100 mg FA; P<0.05), whereas the percentage of vaccenic acid (VA; C18:1 trans- 11) tended to increase (P<0.10) in GS compared with CON. The concentration of VA was higher in MIX than in CON (8.18 vs. 3.77 mg/100 mg FA; P<0.05), whereas RA did not differ between the same groups. The concentration of linoleic acid (LA; C18:2 n –6) decreased and stearic acid (SA; C18:0) increased in all supplemented groups, whereas linolenic acid (LNA; C18:3 n –3) decreased in the two groups receiving grape seed compared with CON and LIN. The concentration of total odd- and branched-chain fatty acids (OBCFA) decreased in all supplemented groups compared with CON (P<0.05), evidencing that grape seed and linseed supplementation influenced the ruminal BH processes. Grape seed was able to increase the accumulation of RA when supplemented alone, and of VA when combined with linseed; however, the rumen accumulation of SA in both groups supplemented with grape seed evidenced that this by-product was not effective in decreasing the BH of dietary polyunsaturated fatty acids (PUFA). [ABSTRACT FROM AUTHOR]

Abstract: The relationship between goat milk fatty acid composition, especially trans-11 C18:1 (vaccenic acid, VA), conjugated linoleic acid (CLA) and n −3 fatty acids, and that of the meat from their suckling kids was investigated by feeding the dams a diet supplemented with whole cottonseed (COT) or extruded linseed (LIN). Fifteen Sarda goats, fed 1.2 kg/day per head of concentrate and hay ad libitum, were divided into two groups and supplemented during weeks 4 and 5 post-partum with 32 g/day per head of fat from LIN and COT, which have high C18:3 and C18:2 content, respectively. Fifteen kids were fed exclusively by suckling maternal milk until slaughtering (at 9–10 kg of body weight and approximately 6 weeks of age). Twenty-four hour after slaughter, the longissimus dorsi (LD) muscle was removed from each carcass. Fatty acid profiles of milk and LD were significantly affected by diets. Compared to COT, feeding LIN changed the milk fatty acid profiles by decreasing the proportion of C16:0 and increasing the contents of VA, C18:3 n −3 (linolenic acid) and total CLA, including cis-9, trans-11-, trans-11, cis-13-, trans-11, trans-13- and trans, trans isomers. The concentrations of VA, cis-9, trans-11 C18:2 (rumenic acid, RA) and linolenic acid in milk and those in kid muscle were strongly correlated. The fatty acid profile of meat from suckling kids was effectively modified by manipulating the diet of the dams. [Copyright &y& Elsevier]

The seasonal variation in conjugated linoleic acid (CLA) and vaccenic acid (VA) concentrations in sheep dairy products and the extent of their transfer from milk fat to cheese and ricotta fat were investigated. Samples were collected from 2 sheep milk processing plants in North Sardinia (Italy) every 2 wk from March through June. Concentrations of fatty acids (FA) in fresh cheese and ricotta fat were primarily dependent on the fatty acid content of the unprocessed raw milk. The content of c9,t11-CLA averaged 1.73, 1.69, and 1.75 mg/100 mg of FA methyl esters (FAME), respectively, for milk, cheese, and ricotta, and differed significantly between cheese and ricotta. The content of VA averaged 3.40, 3.33, and 3.43 mg/100 mg of FAME, respectively for milk, cheese, and ricotta. The FA composition of dairy products was markedly affected by period of sampling: the mean c9,t11-CLA and VA concentration decreased from March (2.20 and 4.52 mg/100 mg of FAME) to June (1.14 and 1.76 mg/100 mg of FAME) in all dairy products. No differences in c9,t11-CLA and VA concentration of dairy products were observed between the 2 dairy companies obtaining milk from the same geographical origin. The seasonal changes in CLA and VA in milk fat were probably related to changes in pasture quality. [ABSTRACT FROM AUTHOR]

The aim of this study was to test the effect of replacing soybean hulls with different doses of cocoa husk (CH) on milk production traits and the hematological profile of dairy ewes. Twenty-four mid-lactating Sarda dairy ewes were allotted to 3 homogeneous experimental groups (8 animals per group divided into 4 pens). Each group received a total mixed ration as a basal diet and a supplement that differed among groups. The first group was supplemented with 100 g of soybean hulls/d per head (SBH group). In the second group, soybean hulls were replaced with 50 g of CH/d (CH50 group). In the third group, soybean hulls were replaced with 100 g of CH/d per head (CH100 group). The study lasted 8 wk, with 3 wk of adaptation and 5 wk for the experimental period. The replacement of soybean hulls with 50 and 100 g of CH/d did not affect dry matter intake, milk production, and milk coagulation properties. Milk fat, protein, casein, and somatic cell count concentration and curd-firming time showed a significant interaction between treatment and sampling date. During the experiment, the somatic cell counts were lower in both the CH50 and CH100 groups than in the SBH group. Most of the hematological parameters were not affected by treatments except for basophiles, which were significantly higher in the SBH group than in the CH50 and CH100 groups. In conclusion, CH can be substituted for soybean hulls in the diet of dairy sheep without adverse effects on milk production or apparent negative effects on animal health conditions. [ABSTRACT FROM AUTHOR]

Summary: In the present study, a sample of 88 animals belonging to four local (Modicana, Sarda, Sardo‐Bruna and Sardo‐Modicana) and one cosmopolitan (Italian Brown Swiss) cattle breeds were genotyped with a medium density SNP beadchip and compared to investigate their genetic diversity and the existence of selection signatures. A total of 43 012 SNPs distributed across all 29 autosomal chromosomes were retained after data quality control. Basic population statistics, Wright fixation index and runs of homozygosity (ROH) analyses confirmed that the Italian Brown Swiss genome was shaped mainly by selection, as underlined by the low values of heterozygosity and minor allele frequency. As expected, local cattle exhibited a large within‐breed genetic heterogeneity. The FST comparison revealing the largest number of significant SNPs was Sardo‐Bruna vs. Sardo‐Modicana, whereas the smallest was observed for Italian Brown Swiss vs. Sardo‐Modicana. Modicana exhibited the largest number of detected ROHs, whereas the smallest was observed for Sardo‐Modicana. Signatures of selection were detected in genomic regions that harbor genes involved in milk production traits for Italian Brown Swiss and fitness traits for local breeds. According to the results of multi‐dimensional scaling and the admixture analysis the Sardo‐Bruna is more similar to the Sarda than to the Italian Brown Swiss breed. Moreover, the Sardo‐Modicana is genetically closer to the Modicana than to the Sarda breed. Results of the present work confirm the usefulness of single nucleotide polymorphisms in deciphering the genetic architecture of livestock breeds. [ABSTRACT FROM AUTHOR]

Exhausted myrtle berries (EMB) is a by-product of the maceration process of myrtle ( Myrtus communis L.) berries to produce a commercial liqueur called Mirto. This study evaluated the effect of the dietary inclusion of EMB on milk production traits, milk coagulation properties, liver and kidney metabolic activity and nitrogen balance in lactating dairy ewes. Thirty Sarda dairy ewes were randomly assigned to 3 dietary treatments consisting of a control diet (CON), a diet supplemented with 50 g/d per head of EMB (EMB50), or a diet supplemented with 100 g/d per head of EMB (EMB100). The study lasted 13 weeks, with 2 weeks of adaptation period and 11 weeks of experimental period. Milk yield was measured and milk samples were collected weekly and analyzed for fat, protein, casein, lactose, milk urea (MU) content and somatic cell count (SCC). Milk samples collected every two weeks were analyzed for milk coagulation properties. Blood samples were collected on d 0, 15, 30, 45 and 60 of the experiment by jugular vein puncture and analyzed for hematological parameters, albumin, alkaline phosphatase (ALP), bilirubin, creatinine, gamma-glutamyltransferase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), protein, blood urea (BU), and serum protein fractions. Dietary treatments did not affect milk yield, composition and coagulation properties, except for MU, which decreased as the dose of EMB in the diet increased, and SCC. Diets did not influence hematological, kidney and liver parameters, except for BU content and blood protein, which decreased with the inclusion of EMB in the diet. The reduction in MU and BU as EMB dose increased suggests that the EMB use might positively affect the dietary nitrogen use. The limited variation in milk production traits, and hematological and metabolic parameters suggests that EMB can be included in the diet of dairy ewes without adverse effects on milk production and health status. [ABSTRACT FROM AUTHOR]

Infections by gastrointestinal nematodes negatively affect small ruminant health and at the same time cause substantial economic losses worldwide. Because resistance to conventional anthelmintic compounds is growing, target studies evaluating the effectiveness of alternative ingredients of botanical origin on gastrointestinal nematodes are needed. In this study, we evaluated the in vitro anthelmintic activity of Ruta chalepensis L. extracts on the third-stage larvae of sheep gastrointestinal nematodes. A methanol extract showed the highest anthelmintic activity, with an EC50 = 0.10 ± 0.06 mg/ml after 96 h, while the essential oil had an EC50 = 1.45 ± 1.22 mg/ml after 48 h. Moreover, three secondary metabolites of the essential oil, i.e. 2-decanone, 2-nonanone and 2-undecanone, showed EC50 values of 0.07 ± 0.06, 0.25 ± 0.29 and 0.88 ± 0.73 mg/ml at 24 h, respectively. The present study indicated that the R. chalepensis methanol extract, the essential oil and its metabolites 2-decanone, 2-nonanone and 2-undecanone showed promising anthelmintic activity on gastrointestinal nematodes. [ABSTRACT FROM AUTHOR]

The collection of milk from dairy sheep has to be balanced with the need for the sheep to feed their lambs at the start of their lives. In Sardinia the sheep nurse their lambs for the first 30 days of their lives when the lambs are slaughtered to produce the traditional PGI (Protected Geographical Indication) Sardinian lamb. In this study the traditional Total Suckling (TS) system was compared with a Partial Suckling (PS) method in which the sheep were separated from the lambs during the day, milked in the evening, and then were allowed to nurse the lambs overnight. Since the removal of milk enhances milk production, a larger milk yield in the TS group was expected compared to the PS group. The production and composition of the milk were measured during the suckling period and for four weeks after lamb weaning. The growth rates of the lambs and the characteristics of their carcasses were measured after slaughter and an economic evaluation of the milk production to compare the two systems was conducted. Sheep in the Partial Suckling group produced 562 g of milk/day more than the sheep in the TS group during the suckling period and 168 g/day more milk than the sheep in the PS group after the lambs were slaughtered. This resulted in extra returns of about 10 €/ewe compared to the traditional TS technique. Although the milk fat concentration was lower in the milk of the PS sheep during the nursing period (4.6% vs. 6.3%; P < 0.01) this rose to 5.4% as soon as the lambs were slaughtered and was not different from that of the TS group (5.6%; P > 0.05). There were no significant differences in the characteristics of the carcasses of the two groups of lambs, with the exception of the cold dressing percentage, which was significantly lower in carcasses from the PS group (60% vs. 65.5%; P < 0.05). It can be therefore concluded that PS allows harvesting more milk than the TS traditionally adopted by Sardinian shepherds thus resulting in greater returns from the sale of milk. In addition, this rearing system did not affect the production and quality of meat from the lambs. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of the dietary inclusion of grape seed, alone or in combination with linseed, on milk production traits, immune response, and liver and kidney metabolic activity of lactating ewes. Twenty-four Sarda dairy ewes were randomly assigned to 4 dietary treatments consisting of a control diet (CON), a diet containing 300 g/d per head of grape seed (GS), a diet containing 220 g/d per head of extruded linseed (LIN), and a diet containing a mix of 300 g/d per head of grape seed and 220 g/d per head of extruded linseed (MIX). The study lasted 10 wk, with 2 wk of adaptation period and 8 wk of experimental period. Milk yield was measured and samples were collected weekly and analyzed for fat, protein, casein, lactose, pH, milk urea nitrogen, and somatic cell count. Blood samples were collected every 2 wk by jugular vein puncture and analyzed for hematological parameters, for albumin, alkaline phosphatase, bilirubin, creatinine, gamma glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, protein, blood urea nitrogen, and for anti-albumin IgG, IL-6, and lymphocyte T-helper (CD4+) and lymphocyte T-cytotoxic (CD8+) cells. On d 0, 45, and 60 of the trial, lymphocyte response to phytohemagglutinin was determined in vivo on each animal by measuring skinfold thickness (SFT) at the site of phytohemagglutinin injection. Humoral response to chicken egg albumin was stimulated by a subcutaneous injection with albumin. Dietary treatments did not affect milk yield and composition. Milk urea nitrogen and lactose were affected by diet x period. Diets did not influence hematological, kidney, and liver parameters, except for blood urea nitrogen, which decreased in LIN and increased in MIX compared with CON and GS. Dietary treatments did not alter CD4+, CD8+, and CD4+-to-CD8+ ratio. The SFT was reduced in GS and MIX and increased in LIN compared with CON. The IgG and IL-6 were affected by diet x period. The reduction in IgG on d 60 and SFT in ewes fed GS suggests an immunomodulatory effect of this residue. The limited variation in milk and hematological and metabolic parameters suggests that GS and LIN can be included, alone or in combination, in the diet of dairy ewes without adverse effects on milk production and health status. [ABSTRACT FROM AUTHOR]

The effects of short-term feed restriction on milk yield and milk composition of Sarda dairy ewes were studied in a 17-d experiment. Twenty sheep were housed in individual pens and divided in two isoproductive groups. Ten ewes (feed restricted group, FRG) were fed a total mixed ration pelleted diet (TMR-PD) ad libitum (average intake of 2.5 kg/head per day) for 7 days (preliminary period), followed by 3 days of feed restriction of 50% of their previous intake (1.25 kg/head per day of TMR-PD) and 7 days of recovery. The other ten ewes (control, C group) were fed TMR-PD ad libitum during all the experimental period (average intake of 2.5 kg/head per day). There were no differences in milk yield between the two groups during the preliminary period (1485 and 1493 g/d for FRG and C group, respectively). Milk yield for the FRG decreased during the feed restriction period and averaged 72% of the values of the C group (1009 vs 1389 g/d, P≤0.001). Milk yield of the FRG was not completely restored during the 7-d recovery period, remaining lower than that of the C group (1278 vs 1451 g/d, P=0.12). Fat percentage tended to increase in FRG during the feed restriction period (5.87% vs 5.27%, P=0.08), and remained higher than that of the C group during recovery (6.04% vs 5.20%, P≤0.01). No effects of feed restriction on protein percentage (5.52% vs 5.53% for FRG and C group, respectively) were observed. SCC was lower in the FRG than in the C group during the preliminary period (Ln SSC 4.51 vs 4.71, P=0.06), increased by more than 4 fold during the feed restriction period (Ln SSC 5.34 vs 4.76, P=0.02) and remained higher during the recovery period (Ln SSC 5.4 vs 4.8, P=0.10). Short-term feed restriction caused a permanent drop in milk production and an increase in SCC on dairy ewes. [ABSTRACT FROM AUTHOR]

During feed restriction, changes in metabolism occur and often result in the mobilization of energy from the adipose tissue. The objective of this work was to evaluate changes in the fatty acid (FA) profile of milk fat during short-term feed restriction in dairy ewes. Six ewes (3 at low-body condition score and 3 at high-BCS) were fed a complete pelleted diet (CPD) ad libitum (average intake of 2.5 kg/head per d) for 7 days, followed by 3 days of feed restriction of 50% of their previous intake (feed restriction group, FRG). Other 6 ewes (control, C group), divided into 3 low-BCS and 3 high-BCS sheep, were always fed CPD ad libitum (average intake of 2.5 kg/head per d). The CPD composition was (on a DM basis) 38.3% NDF, 16.0% CP and 4.5% EE (of which 2% of palm oil). The data of the 3-d treatment were analysed by a mixed model using BCS, group and their interaction as fixed factors and ewe as random factor. Milk fat content was higher in the FRG than in the C group (5.92 vs 4.67%), whereas fat yield was similar between groups. No effects of short-term feed restriction on C4-C14 fatty acids were observed. The FRG showed a lower content of C16:0 (26.46 vs 29.59%; P≤0.05) and cis9,cis12 C18:2 (4.42 vs 5.38%; P≤0.10) and a higher content of cis9 C18:1 (20.81 vs 17.56%; P≤0.05) than the C group. The content of total CLA (1.47 and 1.27 in the FRG and C group, respectively) was not influenced by the feed restriction treatment. The extent of variation in milk fatty acid profile in FRG group (expressed as percentage respect to C group) was influenced by BCS of ewes. The results suggest that feed restriction for a 3-d period is enough to cause changes in the FA profile of milk fat. The different responses observed in animals with high and low BCS was probably due to a different extent of body store mobilization when feed restriction occurred. [ABSTRACT FROM AUTHOR]