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The present study investigated the effect of heat-treated colostrum feeding on the bacterial colonization in calf small intestine of neonatal calves within the first 12h of life. Newborn Holstein bull calves (n=32) were assigned to 3 treatment groups and fed with either fresh colostrum (FC, n=12) or heat-treated (60°C, 60 min) colostrum (HC, n=12) soon after birth, whereas the control (NC, n=8) group did not receive colostrum or water. Small intestinal tissues and contents were collected from proximal jejunum, distal jejunum, and ileum at 6 and 12h after birth, following euthanasia. Quantitative real time-PCR was used to explore the colonization of total bacteria, Lactobacillus, Bifidobacterium, and Escherichia coli. The feeding of colostrum soon after birth increased the colonization of total bacteria in calf gut within the first 12h compared with NC. In contrast, the prevalence of Lactobacillus was lower in HC and FC compared to NC. Remarkable changes in the prevalence of small intestinal tissue-attached Bifidobacterium were observed with the feeding of HC, but not that in small intestinal contents. The prevalence of Bifidobacterium was 3.2 and 5.2 fold higher in HC than FC and NC, respectively, at 6h. Although the feeding of FC did not enhance the prevalence of tissue-attached Bifidobacterium at 6h compared with NC, it displayed a gradual increase over the time that was higher than NC, but similar to that of HC at 12h. Moreover, the colonization of E. coli was drastically reduced in HC calves compared with FC and NC. Thus, the present study suggests that the feeding of HC enhances the colonization of Bifidobacterium but lessens E. coli in the calf small intestine immediately postpartum compared with that of FC and NC. The increased colonization of beneficial bacteria along with the decreased colonization of potential pathogens in calf gut may also diminish the neonatal calf diarrhea when calves are fed heat-treated colostrum soon after birth.

Community sports settings are often sources of unhealthy foods for children. Many managers in these settings are reluctant to increase availability of healthy food options because they perceive that healthy foods are not profitable. This study assessed the independent contribution of increased availability of healthy foods to their sales in a community sport, commercial context. Change in revenues per patron was also examined.The availability of healthy items was increased from 9.1% at baseline (35 days) to 25.0% during the intervention period (40 days), returning to 9.1% postintervention (6 days). Purchases of all patrons who bought foods/beverages (n=17,262 items sold) from two concessions at an outdoor community pool were assessed from baseline to postintervention. Chi-square analyses assessed differences in the proportion of healthy and unhealthy items sold, as well as in the proportion of total revenues per patron across periods. A trained observer also recorded qualitative observations pertaining to a subset of patrons' (n=221) dietary behaviors and activities.Healthy items represented 7.7%, 22.7%, and 9.8% of sales during the preintervention, intervention, and postintervention periods, respectively (p0.01). Sales of healthy beverages exceeded sales of all other product types. The proportion of total revenues per patron did not differ by period.Food availability was an important environmental determinant of food purchasing behaviors in this community commercial context, given that sales of healthy foods closely mirrored their availability. Increased availability of healthy foods in community and commercial settings is important because concurrent changes within multiple environments will be required to improve children's dietary behaviors.

Residual Feed Intake (RFI) is a measure of energy efficiency. Developing an appropriate model to predict expected energy intake while accounting for multifunctional energy requirements of metabolic body weight (MBW), empty body weight (EBW), milk production energy requirements (MPER), and their nonlinear lactation profiles, is the key to successful prediction of RFI in dairy cattle. Individual daily actual energy intake and monthly body weight of 281 first-lactation dairy cows from 1 to 305 d in milk were recorded at the Dairy Research and Technology Centre of the University of Alberta (Edmonton, AB, Canada); individual monthly milk yield and compositions were obtained from the Dairy Herd Improvement Program. Combinations of different orders (1-5) of fixed (F) and random (R) factors were fitted using Legendre polynomial regression to model the nonlinear lactation profiles of MBW, EBW, and MPER over 301 d. The F5R3, F5R3, and F5R2 (subscripts indicate the order fitted) models were selected, based on the combination of the log-likelihood ratio test and the Bayesian information criterion, as the best prediction equations for MBW, EBW, and MPER, respectively. The selected models were used to predict daily individual values for these traits. To consider the body reserve changes, the differences of predicted EBW between 2 consecutive days were considered as the EBW change between these days. The smoothed total 301-d actual energy intake was then linearly regressed on the total 301-d predicted traits of MBW, EBW change, and MPER to obtain the first-lactation RFI (coefficient of determination=0.68). The mean of predicted daily average lactation RFI was 0 and ranged from -6.58 to 8.64 Mcal of NE(L)/d. Fifty-one percent of the animals had an RFI value below the mean (efficient) and 49% of them had an RFI value above the mean (inefficient). These results indicate that the first-lactation RFI can be predicted from its component traits with a reasonable coefficient of determination. The predicted RFI could be used in the dairy breeding program to increase profitability by selecting animals that are genetically superior in energy efficiency based on RFI, or through routinely measured traits, which are genetically correlated with RFI.

The effect of providing a lipid emulsion containing medium-chain triglyceride (MCT), soybean oil, and fish oil in critically ill infants is not widely studied. This study investigated lipid emulsion effects on plasma phospholipids and immune biomarkers.Thirty-two infants undergoing cardiopulmonary bypass (CPB) and dependent on parenteral nutrition (PN) were randomized to receive either soybean oil (control, n = 16) or a 50:40:10 mixture of MCT, soybean oil, and fish oil (treatment, n = 16). PN was administered for 3 days preoperatively and 10 days postoperatively. Fatty acids, procalcitonin (PCT), leukotriene B4 (LTB4), and lymphocytes were quantified at baseline, before surgery, and days 1, 7 and 10 after surgery.PCT was significantly lower in the treatment vs control group 1 day postoperatively (P = .01). The treatment group exhibited a lower ω-6 to ω-3 ratio (P = .0001) and a higher ω-3 concentration at all postoperative study periods (P = .001). Treatment resulted in higher (P.05) plasma phospholipid eicosapentaenoic acid (EPA) on days 7 and 10, while α-linolenic acid, arachidonic acid, and docosahexaenoic acid remained constant. An increase in plasma phospholipid EPA concentration was associated with a decrease in plasma phospholipid LTB4 concentration (P.05). On postoperative day 10, treatment infants with high Pediatric Risk of Mortality III scores exhibited a 45% lower lymphocyte concentration (P.05).These findings suggest that treating infants undergoing CPB with a lipid emulsion containing ω-3 improves fatty acid status and results in a lower inflammatory response after surgery. Overall, this alternative ω-3-enriched lipid emulsion may benefit clinical outcomes of critically ill infants after cardiac surgery.

There is concern in the beef industry that selecting bulls for feed efficiency based on residual feed intake (RFI) may have a negative impact on bull reproductive performance and fertility. Here we investigated the impact of selection of bulls for low RFI on breeding soundness evaluation (BSE), reproductive performance, and fertility of bulls under natural service in multi sire mating groups on pasture. Of the 412 RFI-tested bulls available, 98 (23.8%) were culled for performance, type, temperament, or other reasons, and 88 (21.4%) were culled for failing BSE, for an overall cull rate of 45.1%. From among the 314 bulls subjected to BSE, 32 (10.2%), 20 (6.4%), and 36 (11.4%) were culled for poor feet and legs, scrotal circumference, and semen quality, respectively. The BSE traits were not different (P > 0.10) between bulls categorized as either inefficient (+RFI) or efficient (-RFI), but the proportion of bulls that failed to meet the 60% minimum sperm motility requirement tended (P = 0.07) to be greater in the -RFI group than in the +RFI group (10.2% vs. 4.4%, respectively). In a subpopulation of 115 bulls, individual progressive sperm motility was greater (P < 0.05) in +RFI(85%) than - RFI(80%) bulls. A multi sire natural mating experiment was conducted during 2 consecutive breeding seasons (2006 to 2007 and 2007 to 2008) using 18 +RFI and 18 -RFI bulls. The overall calving rate (calves born/cows exposed) was 72.9%. Mean number of progeny per sire was significantly greater (P < 0.01) in -RFI bulls (18.3) than in +RFI bulls (11.8). Selection for feed efficiency based on RFI appears to have no detrimental impact on reproductive performance and fertility in beef bulls bred in multi sire groups on pasture. However, the decreased sperm motility and the greater number of progeny per sire associated with -RFI status need further investigation.

Summary Background & aims This study assessed the effects of administering a lipid emulsion containing eicosapentaenoic and docosahexaenoic acid before and after open-heart surgery on cytokine production and length of hospital stay in infants. Methods Thirty-two infants (40 ± 2.3 weeks gestational age; 10.6 days at time of surgery) undergoing open-heart surgery with cardiopulmonary bypass were randomized to receive an intravenous lipid emulsion with (treatment) or without (control) eicosapentaenoic and docosahexaenoic acid in this prospective, randomized, double-blind, controlled trial. Results Mean plasma TNF-α concentration was significantly (p = 0.003) lower in the treatment (5.9 pg/mL) compared to the control group (14.8 pg/mL). In infants without sepsis, plasma TNF-α did not differ according to treatment, however when sepsis developed, mean plasma TNF-α was 21.1 pg/mL and 1.5 pg/mL (p = 0.0007) in control and treatment groups, respectively. Plasma TNF-α was positively correlated with length of hospital stay in the control group (p = 0.01), and negatively correlated with length of stay in the treatment group (p = 0.004), with a significant time by treatment interaction (p = 0.02). Conclusions Providing a lipid emulsion containing eicosapentaenoic and docosahexaenoic acid reduces TNF-α concentrations in infants undergoing open-heart surgery. Lipid emulsions containing eicosapentaenoic and docosahexaenoic acid may ameliorate the inflammatory response among critically ill infants. This trial was registered at clinicaltrials.gov as NCT00336908.

The influence of rumen microbial structure and functions on host physiology remains poorly understood. This study aimed to investigate the interaction between the ruminal microflora and the host by correlating bacterial diversity with fermentation measurements and feed efficiency traits, including dry matter intake, feed conversion ratio, average daily gain, and residual feed intake, using culture-independent methods. Universal bacterial partial 16S rRNA gene products were amplified from ruminal fluid collected from 58 steers raised under a low-energy diet and were subjected to PCR-denaturing gradient gel electrophoresis (DGGE) analysis. Multivariate statistical analysis was used to relate specific PCR-DGGE bands to various feed efficiency traits and metabolites. Analysis of volatile fatty acid profiles showed that butyrate was positively correlated with daily dry matter intake ( P < 0.05) and tended to have higher concentration in inefficient animals ( P = 0.10), while isovalerate was associated with residual feed intake ( P < 0.05). Our results suggest that particular bacteria and their metabolism in the rumen may contribute to differences in host feed efficiency under a low-energy diet. This is the first study correlating PCR-DGGE bands representing specific bacteria to metabolites in the bovine rumen and to host feed efficiency traits.

A Macronutrient Preference Checklist (MPC) is a simple tool that assesses momentary macronutrient and taste preferences. The purpose of this study was to modify and validate an existing European 32-item MPC and adapt it for use in North America. A total of 160 subjects completed questionnaires (demographic survey, appetite assessment, MPC, and MPC items rated on a 9-pt hedonic scale) on two occasions (Part 1). The MPC showed good internal consistency (Cronbach's alpha values of 0.76, 0.72, 0.64, and 0.57 for the four macronutrient categories of high protein, high carbohydrate, high fat, and low energy) and high test–retest reliability, with strong correlations for all four macronutrient categories. A larger sample size (n = 239) was used to explore the influences of age, gender, and appetite on macronutrient and taste preference (Part 2). Subjects completed study questionnaires once. The influences of appetite, age, and gender on macronutrient preferences assessed with the MPC concur with the literature, confirming the tool's validity. The MPC was found to be a valid and reliable tool that may be used as a simple and efficient method of assessing momentary macronutrient and taste preferences in future research and clinical settings in North America.

Steaks from corn-fed and barley-fed beef were characterized by a trained panel, which rated corn-fed beef higher (p0.05) for tenderness attributes and overall flavor intensity. Canadian consumers preferred (p0.01) cooked and raw steaks from barley-fed beef, while Mexican consumers showed no preference (p0.05) for either type of finished beef. Japanese consumers showed a preference (p0.05) for the appearance of raw barley-fed steaks but a preference for cooked corn-fed steaks (p0.05). No differences (p0.05) were observed for Warner-Bratzler shear, marbling scores, cooking losses or Hunter colorimeter values. There was a trend for higher concentrations (p0.08) of the saturated fatty acids in the barley treatment, but no differences (p0.10) in mono or polyunsaturated fatty acids.

The objective was to evaluate different levels of sun-flower oil (SFO) in dairy rations to increase vaccenic (trans-11-18:1) and rumenic acids (cis-9,trans-11-18:2) in milk fat, and assess the content and composition of other trans-octadecenoic (trans-18:1) and conjugated linoleic acids (CLA) isomers. Eighty lactating Holstein cows were fed control diets for 4 wk and then placed on 4 diets for 38 d; milk fat was analyzed after 10 and 38 d. The treatments were: control, 1.5% SFO plus 0.5% fish oil (FO), 3% SFO plus 0.5% FO, and 4.5% SFO plus 0.5% FO. The forage-to-concentrate ratio was 50:50 and consisted of barley/alfalfa/hay silage and corn/barley grain concentrate. There were no differences in milk production. Supplementation of SFO/FO reduced milk fat compared with respective pretreatment periods, but milk protein and lactose levels were not affected. There was a linear decrease in all short- and medium-chain saturated fatty acids (SFA) in milk fat after 10 d (25.5, 24.1, 20.2, and 16.7%) and a corresponding linear increase in total trans-18:1 (5.2, 9.1, 14.1, and 21.3%) and total CLA (0.7, 1.9, 2.4, and 3.9%). The other FA in milk fat were not affected. Separation of trans-18:1 isomers was achieved by combination of gas chromatography (GC; 100-m highly polar capillary column) and prior separation of trans FA by silver ion-thin layer chromatography followed by GC. The CLA isomers were resolved by a combination of GC and silver ion-HPLC. The trans-11- and trans-10-18:1 isomers accounted for approximately 50% of the total trans-18:1 increase when SFO/FO diets were fed. On continued feeding to 38 d, trans-11-18:1 increased with 1.5% SFO/FO, stayed the same with 3%, and declined with 4.5% SFO/FO. Rumenic acid showed a similar pattern on continued feeding as trans-11-18:2; levels increased to 0.43, 1.5, 1.9, and 3.4% at 10 d and to 0.42, 2.15, 2.09, and 2.78% at 38 d. Rumenic acid was the major CLA isomer in all 4 diets: 66, 77, 78 and 85%. The CLA isomers trans-7,cis-9-, trans-9,cis-11-, trans-10,cis-12-, trans-11,trans-13-, and trans-9,trans-11-/trans-10,trans-12-18:2 also increased from 0.18 (control) to 0.52% (4.5% SFO/FO). Milk fat produced from 3% SFO/FO appeared most promising: trans-11-18:1 and cis-9,trans-11-18:2 increased 4.5-fold, total SFA reduced 18%, and moderate levels of trans-10-18:1 (3.2%), other trans-18:1 (6.6%) and CLA isomers (0.5%) were observed, and that composition remained unchanged to 38 d. The 4.5% SFO/FO diet produced higher levels of trans-11-18:1 and cis-9,trans-11-18:2, a 28% reduction in SFA, and similar levels of other trans-18:1 (9.2%) and CLA isomers (0.52%), but the higher levels of trans-11-18:1 and cis-9,trans-11-18:2 were not sustained. A stable milk fat quality was achieved by feeding moderate amounts of SFO (3% of DM) in the presence of 0.5% FO that had 4% vaccenic and 2% rumenic acids.

SUMMARYNine spring wheat cultivars, selected on the basis of height, tillering capacity and maturity, were grown in differing levels of natural weed presence at three locations in Edmonton and New Norway, Alberta between 2003 and 2004. The objectives of the study were to (1) identify competitive traits in wheat cultivars, (2) determine whether traits associated with competitive ability differ under increasing weed pressure and (3) assess cultivar stability in and adaptation to environments differing in yield potential and weed competition. Eight experimental environments (including conventionally and organically managed fields with and without common oats sown as a weed analogue) were grouped into low, medium and high weed pressure levels, based on mean total weed biomass. Tallness and early heading and maturity were related to increased grain yield at the highest weed level. Greater spikes/m2, tallness and early heading were associated with reduced weed biomass, depending on weed level. Principal component analysis (PCA) revealed that height accounted for a small amount of variation in low weed environments, yet was more important as weed pressure increased. Finlay–Wilkinson (Finlay & Wilkinson 1963) stability analysis demonstrated that cultivars responded differently in environments differing in yield potential and in weed pressure. Older wheat cultivars were generally more yield-stable across environments, while modern semidwarf cultivars were more sensitive to changes in weed level. The cultivar Park (released in 1963) was the most yield- and weed-stable cultivar, coupled with relatively high yields and average weed biomass accumulation, and may therefore be well adapted to low yielding or high weed environments.

This study was conducted to determine the optimum test duration and the effect of missing data on accuracy of measuring feed efficiency and its 4 related traits ADG, DMI, feed conversion ratio, and residual feed intake in beef cattle using data from 456 steers with 5,397 weekly averaged feed intakes and BW repeated measurements taken over 91 d. Data were collected using the GrowSafe System at the University of Alberta Kinsella Research Station. The changes and relative changes in phenotypic residual variances and correlations (Pearson and Spearman) among data from shortened test durations (7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, or 84 d) and a 91-d test were used to determine the optimum test duration for the 4 traits. The traits were fitted to a mixed model with repeated measures using SAS. Test durations for ADG, DMI, feed conversion ratio, and residual feed intake could be shortened to 63, 35, 42, and 63 d, respectively, without significantly reducing the accuracy of the tests when BW was measured weekly. The accuracy of the test was not compromised when up to 30% of the records were randomly removed after the first 35 d on test. These results have valuable and practical implications for performance and feed efficiency testing in beef cattle.

Background: In the current literature, no agreement exists on estimates for aromatic amino acid (phenylalanine plus tyrosine) requirements as measured by stable-isotope techniques. Objective: The goal of the present study was to determine the phenylalanine requirement in healthy men who were fed a diet without tyrosine by using the indicator amino acid oxidation method. Design: Five healthy men were assigned to receive in random order diets devoid of tyrosine and with 8 graded intakes of phenylalanine (5, 10, 15, 25, 35, 45, 60, and 70 mg.kg -1 . d -1 ). The phenylalanine requirement was measured by the rate of 13 CO 2 release (F 13 CO 2 ) from L-[1- 13 C]lysine oxidation. Results: The graded intakes of phenylalanine had no effect on lysine flux, as required for this method. The phenylalanine (ie, total aromatic amino acid) requirement, in the absence of tyrosine, was estimated to be 48 mg . kg -1 . d -1 by applying a two-phase linear regression crossover model to the F 13 CO 2 data. Conclusions: In the absence of tyrosine, the mean phenylalanine requirement is higher than the current FAO/WHO/UNU (1985) and Dietary Reference Intake (2002) recommendations.

Summary We initiated a proteomics-based approach to identify root proteins affected by salinity in pea (Pisum sativum cv. Cutlass). Salinity stress was imposed either on 2-wk old pea plants by watering with salt water over 6 wk or by germinating and growing pea seeds for 7 days in Petri dishes. Concentrations of NaCl above 75 mM had significant negative effects on growth and development of peas in both systems. Salinity-induced root proteome-level changes in pea were investigated by 2-D electrophoresis of proteins from control, 75 and 150 mM NaCl-treated plants and seedlings. The majority of the protein spots visualised showed reproducible abundance in root protein extracts from whole plants and seedlings. Of these proteins, 35 spots that exhibited significant changes in abundance due to NaCl treatment were selected for identification using ESI-Q-TOF MS/MS. The identities of these proteins, which include pathogenesis-related (PR) 10 proteins, antioxidant enzymes such as superoxide dismutase (SOD) as well as nucleoside diphosphate kinase (NDPK) are presented, and the roles of some of them in mediating responses of pea to salinity are discussed. This is the first report of salinity-induced changes in the root proteome of pea that suggests a potential role for PR10 proteins in salinity stress responses. Our findings also suggest the possible existence of a novel signal transduction pathway involving SOD, H2O2, NDPK and PR10 proteins with a potentially crucial role in abiotic stress responses.

Astringent and bitter sensations are characteristic sensory qualities of black tea. Three different classes of potential astringent reference standards (two concentrations each of alum and tannic acid and three fruit juices) were evaluated in this study. The perceived astringency, bitterness and sourness of each were profiled using computerized time-intensity and compared with the astringent intensity of a standardized brew of black tea. The differences in temporal profiles of potential reference standards across taste attributes were evident and intensity ratings were found to be dependent upon the stimulus and its concentration. Both concentrations of tannic acid were evaluated as the highest in perceived bitterness. For the juices, a strong sour taste was perceived in addition to astringency. It was concluded that the best reference standard for the astringency of black tea is a solution of 0.7 g/L alum as it is low in perceived bitterness and sourness.

Ninety-six weaned calves (48 bulls and 48 heifers) were allocated in a 2 ×2 ×2 arrangement to 3 treatments each with 2 levels: calves handled every 10 days or 20 days; an electric goad used or not used; and head gate restrained or not restrained. Behavior responses were measured by 5 incremental progressive force requirement (PFR) categories and transit time (TT). The PFRs were transformed to maximum force scores (MFS) for analysis (Snell, 1964). TT was the time taken for calves to move 11 m along a chute. During the study, 52%, 36%, 5%, 3%, and 5% of the cattle were observed in Categories 1, 2, 3, 4, and 5, respectively. Cattle handled every 10 days showed a 36.0% higher MFS (p < .03) and a 24.5% higher TT (p < .02) than cattle handled every 20 days. The MFS and TT for head gate-restrained calves were 33.0% (p < .03) and 15.5% higher (p < .02), respectively, compared to calves not restrained in the head gate. Cattle developed a reluctance to frequent handling early in the study and an aversion to head ga...

Four Alpine does were used in a 4 × 4 Latin square design to determine the effects of feeding canola oil at four levels: 0 (no oil), 2% (40 g), 4% (80 g) and 6% (120 g) of grain intake, on milk constituents, conjugated linoleic acid (CLA) and long chain fatty acids. Milk fat percent was highest and lowest ( p p > 0.05) on milk yield, percent protein and lactose, C 18:2 and C 18:3 fatty acids. The CLA in milk increased ( p −1 fat when does were fed 2 and 4% canola oil, respectively. There were linear and quadratic increases ( p 18:1 and a quadratic decrease ( p 16 in response to feeding incremental levels of canola oil. The ratio of C 18:0+18:1 to ≤C 16 increased ( p 18:1 to CLA and oleic acid in milk was 52.69 and 0.24, respectively. Changes in milk fat composition are feasible by feeding canola oil to goats, thereby producing a value-added product with a more favorable fatty acid profile.

BACKGROUND Infants with congenital heart lesions who undergo open heart surgery may experience physiologic and metabolic stress in the postoperative period, leading to altered metabolism and hypercatabolism. The purpose of this study was to determine the relationship between energy intake and hospital outcomes during the first 10 days following neonatal open heart surgery. MATERIALS AND METHODS A post hoc analysis of all patients in a prospective randomized controlled trial was performed. Nutrition intake and hospital outcomes were assessed in 32 infants (40 ± 2.2 weeks, 3.4 ± 0.5 kg) in the neonatal and pediatric intensive care units. Infants received parenteral nutrition (PN) for 1-4 days before and 10 days after open heart surgery. Infants were separated into those who received a cumulative energy intake of

Calf starters are usually offered to dairy calves to facilitate the weaning process, however, the effect of solid feed consumption on gut health has not been well studied. This study aimed to investigate the effect of calf starter feeding on the gut bacterial community and mucosal immune functions in dairy calves during weaning transition. Mucosal tissue and digesta samples were collected from rumen, jejunum, ileum, cecum, and colon upon slaughtering of calves (n=8) after feeding the experimental diets [milk replacer (MR) or milk replacer + calf starter (MR+S)] for 6 wk. Expression of toll-like receptor (TLR) 10 was downregulated along the gut, whereas TLR2 in colon and TLR6 along the gut were upregulated in MR+S-fed calves compared with MR-fed calves. Ileal TLR9 and TLR10 showed higher expression compared with the other regions regardless of the diet. Peptidoglycan recognition protein 1 demonstrated a diet- and gut-regional dependent expression pattern, whereas β-defensin did not. The diet and gut region also affected the expression of tight junction-regulating genes claudin 4 and occludin. Bacterial diversity tended to be different between the 2 diets, whereas the bacterial density was different among gut regions and sample type. The present study revealed that changes in bacterial diversity, expression of genes encoding host mucosal immune responses, and barrier functions were associated with the MR+S diet, and suggests that solid feed consumption may alter gut microbiome and host mucosal functions during weaning transition.

Limited knowledge of the structure and activities of the ruminal bacterial community prevents the understanding of the effect of population dynamics on functional bacterial groups and on host productivity. This study aimed to identify particular bacteria associated with host feed efficiency in steers with differing diets and residual feed intake (RFI) using culture-independent methods: PCR-denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR analysis. PCR-DGGE profiles were generated from the ruminal fluid of 55 steers fed a low-energy-density diet and then switched to a high-energy-density diet. Bacterial profile comparisons by multivariate statistical analysis showed a trend only for RFI-related clusters on the high-energy diet. When steers ( n = 19) belonging to the same RFI group under both diets were used to identify specific bacterial phylotypes related to feed efficiency traits, correlations were detected between dry matter intake, average daily gain, and copy numbers of the 16S rRNA gene of Succinivibrio sp. in low-RFI (efficient) steers, whereas correlations between Robinsoniella sp. and RFI ( P < 0.05) were observed for high-RFI (inefficient) animals. Eubacterium sp. differed significantly ( P < 0.05) between RFI groups that were only on the high-energy diet. Our work provides a comprehensive framework to understand how particular bacterial phylotypes contribute to differences in feed efficiency and ultimately influence host productivity, which may either depend on or be independent from diet factors.

The objective of this study was to examine the ethanol yield potential of three barley varieties (Xena, Bold, and Fibar) in comparison to two benchmarks, corn and wheat. Very high gravity (VHG; 30% solids) fermentations using both conventional and Stargen 001 enzymes for starch hydrolysis were carried out as simultaneous saccharification and fermentation. The grains and their corresponding dried distiller's grain with solubles (DDGS) were also analyzed for nutritional and value-added characteristics. A VHG traditional fermentation approach utilizing jet-cooking fermentation revealed that both dehulled Bold and Xena barley produced ethanol concentrations higher than that produced by wheat (12.3, 12.2, and 11.9%, respectively) but lower than that produced by corn (13.8%). VHG-modified Stargen-based fermentation of dehulled Bold barley demonstrated comparable performance (14.3% ethanol) relative to that of corn (14.5%) and wheat (13.3%). Several important components were found to survive fermentation and were concentrated in DDGS. The highest yield of phenolics was detected in the DDGS (modified Stargen 001, 20% solids) of Xena (14.6 mg of gallic acid/g) and Bold (15.0 mg of gallic acid/g) when the hull was not removed before fermentation. The highest concentration of sterols in DDGS from barley was found in Xena (3.9 mg/g) when the hull was included. The DDGS recovered from corn had the highest concentration of fatty acids (72.6 and 77.5 mg/g). The DDGS recovered from VHG jet-cooking fermentations of Fibar, dehulled Bold, and corn demonstrated similar levels of tocopherols and tocotrienols. Corn DDGS was highest in crude fat but was lowest in crude protein and in vitro energy digestibility. Wheat DDGS was highest in crude protein content, similar to previous studies. The barley DDGS was the highest in in vitro energy digestibility.

The early conception factor (ECF) lateral flow test was evaluated for its ability to accurately determine nonpregnant status in dairy cattle. Results of 2 field trials involving 191 cows and 832 tests indicated the probability that a cow can be correctly diagnosed as nonpregnant by using the ECF test is only about 50%. Agreement of test results between milk and serum obtained from the same cow was 57.5%. The ECF test was not consistent in identifying nonpregnancy when the same cows were tested repeatedly over a period of 4 weeks. We conclude that the ECF lateral flow test does not accurately identify nonpregnancy in dairy cattle.

Leucine tracer has been widely used for examining whole-body protein turnover in humans, but has not been evaluated as an indicator to be used in the indicator amino acid oxidation (IAAO) method. The goal of this study was to determine whether the L-[1- 13 C]leucine isotope is an acceptable indicator by comparing it with an established tracer, L-[1- 13 C]lysine. Healthy men (n = 7; 29.9 ± 4.8 y old) were fed in random order a diet with 7 graded intakes of phenylalanine without tyrosine. In the first study (n = 5), subjects were administered an excess leucine intake of 65 mg/(kg.d), and in the second study (n = 5), they were given the mean requirement of 45 mg/ (kg.d) to determine whether leucine intake affected the pattern of response. Previous IAAO studies using lysine and phenylalanine demonstrated a clear pattern in 13 CO 2 production, i.e., increasing test amino acid intake resulted in a linear decrease to plateau, with a readily discernable breakpoint indicating the requirement. This pattern of production of 13 CO 2 , indicates clear partitioning of the indicator amino acid between oxidation and protein synthesis. This was not observed with leucine at an intake of 65 mg/(kg.d). Conversely, at the lower leucine intake of 45 mg/(kg.d), a breakpoint was seen and a total aromatic amino acid requirement estimate that did not differ from that obtain using lysine as the indicator was obtained. In conclusion, leucine may be used as the indicator in the IAAO technique only when the daily intake leucine is given at its mean requirement level and the potential metabolic effects of other variables are taken into consideration.

The aim of this study was to investigate whether the phases of the menstrual cycle affect lysine requirement in healthy adult females, as determined by the indicator amino acid oxidation (IAAO) method. Five healthy females with regular menstrual cycles were studied at seven graded levels of lysine intake, in random order, with an oral [13C]phenylalanine tracer protocol in both the follicular and luteal phases. A total of 14 studies were conducted for each subject. Breath and plasma samples were collected according to the standard IAAO protocol. Serum 17β-estradiol and progesterone concentrations were measured on each IAAO study day. The rate of release of13CO2from [13C]phenylalanine oxidation (F13CO2) was measured, and a two-phase linear regression crossover model was applied to determine lysine requirement. F13CO2was higher during the luteal phase ( P < 0.001) and was positively associated with serum concentrations of 17β-estradiol and progesterone. The F13CO2data were adjusted for subjects and sex hormones and used to define breakpoints for lysine requirements. The lysine requirement of healthy females in the luteal phase was 37.7 mg·kg−1·day−1and higher ( P = 0.025) than that of females in the follicular phase (35.0 mg·kg−1·day−1). At all lysine intake levels, plasma amino acids were lower and phenylalanine oxidation was higher in the luteal relative to the follicular phase. Therefore, we reason that the higher lysine requirement observed in the luteal phase is probably due to higher amino acid catabolism.

The objective of this study was to investigate the effect of 2 levels of prebreeding nutrition on reproduction in yearling does artificially inseminated (AI) by the intrauterine laparoscopic method. Forty-two does (Alpine = 22 and Saanen = 20) were randomly penned in groups of 7 and were fed 1 of 2 diets. The diets contained 3.2 Mcal DE/d (MAINT) or 3.5 Meal DE/d (HIGH), which was 10 and 20% higher than the National Research Council recommendations for maintenance requirements. The does were on the 2 feed treatments for 8 wk, after which the MAINT group was switched to the HIGH group diet. A week later, they were fitted with Veramix sponges to synchronize estrus. The sponges were removed from 22, 10 and 10 randomly picked does after 17, 22 and 23 d, respectively. All the does showed estrus within 48 h of removing the sponges. Previously frozen Alpine or Saanen semen (0.5 ml) was deposited into the uterus of does exhibiting standing estrus after anesthetizing them with zylazine and ketamine. Pure breeding was practiced. All the does lost weight prior to breeding. Seventeen does (41%) conceived and kidded by AI while the rest returned to estrus about 23 d later. A significant difference (P0.05) in the kidding percentage was observed between the 2 breeds (Alpine = 64% and Saanen = 16%), while the kidding percentage between the 2 diets did not differ (P0.05). Of the does that kidded, seven (41%) had singletons, eight (47%) had twins, one had triplets and one had quadruplets. Average litter size (kids/doe kidding) by AI was 1.76. Although the does lost weight prior to breeding, this did not affect their reproduction.

Information on the yield of grasses as the plants mature is useful to optimize grazing potential and quality hay production. The objectives of this study were to compare the yield and feeding value of 11 common prairie grasses over 2 yearly cycles of growth and determine which of the grasses may require supplementation to meet nutrient requirements of grazing cattle. Dry matter yield (DM), crude protein (CP), acid detergent fiber (ADF), calcium (Ca), and phosphorus (P) values were obtained for brome (Bromus inermis [L.]), creeping red fescue (Festuca rubra [L.]), crested wheatgrass (Agropyron cristatum [L.] Gaertn), intermediate wheatgrass (Agropyron intermedium (host) Beauv), meadow foxtail (Alopecurus pratensis [L.]), orchardgrass (Dactylis glomerata [L.]), pubescent wheatgrass (Agropyron trichophorum Link. richt), streambank wheatgrass (Agropyron riparium Scriba &Smith), slender wheatgrass (Agropyron trachycaulum Link Malte), tall fescue (Festuca arundinacea Schreb), and timothy (Phleum pratense [L.]) at weekly intervals from June to September, in 1992 and 1993. Most grasses reached maximum yields at week 8 in 1992 (drought year) and week 12 in 1993 (normal year). Herbage mass yields (g/0.25m2 at week 8 in 1992 (highest to lowest yielding) were crested wheatgrass (235), intermediate wheatgrass(210), pubescent wheatgrass(173), brome(161), slender wheatgrass(152), meadow foxtail(114), Tall fescue(110), timothy(101), orchardgrass(83), creeping red fescue(56), and streambank wheatgrass(50). Herbage mass yields pattern of the grasses in 1993 was similar to that in 1992 except for crested wheatgrass and brome which ranked first and fourth in 1992 but ranked fifth and second, in 1993, respectively. Quality declined in all grasses as they matured. The average CP content of grasses declined from 24% to 13% in 1992 and from 21.5% to 12.1% in 1993 but were adequate to meet crude protein requirements of growing, pregnant or lactating grazing cattle. The Ca levels in all grasses were adequate for all classes of cattle on pasture but the low P levels of 0.11% in both years indicate that growing, pregnant or lactating cattle grazing on these pastures would require P supplementation.