Abstract
This study evaluated the effect of residual gain (RG) on body chemical composition of water buffaloes of three genetic groups (GG:Jafarabadi, Mediterranean, and Murrah) and verify the ...presence of chemical variables related to this efficiency measure. One-hundred-forty-eight non-castrated male (338.29 ±64.16 kg initial body weight; 370 ±28 days of initial age) from two similar experiments were used. The animals remained in feedlot and were slaughtered after 240 days (adaptation+trial periods). The RG was calculated considering 84 days after adaptation period. After the slaughter the empty body weight (EBW) of each animal was obtained and the left half-carcasses were dissected into muscle, fat, and bone, after 24h of cooling. The chemical composition moisture, crude protein (CP), ether extract (EE), and ash of each ground tissue was analyzed by the classical method. The body CP was also determined based on CP fat-free dry matter (CPFFDM). Data were analyzed using MIXED procedure in SAS. The class of RG, genetic group, and the resulting interaction were tested as fixed effect and year as a random effect. The variable results are reported as kg of EBW. There was no interaction effect (P ≥ 0.11) for the variables studied. Effect of class of RG was detected for the variables EBW (P = 0.021), water (P = 0.016), and EE (P = 0.035), while tendency was observed for CP (P = 0.074), for which animals classified as more efficient for residual gain demonstrated high values (Table 1). Furthermore, there was effect of GG for EBW (P = 0.002), water (P < 0.001), and CP (P = 0.014) variables. Tendency of GG effect was observed for ash (P = 0.085) and EE (P = 0.057). Jafarabadi showed high values for all the variables cited. In conclusion, there are difference in the body chemical composition of water buffaloes according to the animal efficiency evaluated by residual gain, as well as according to genetic groups. Supported by FAPESP (#2014/05473-7).
Abstract
Fiber is known for decreasing nutrient utilization in pigs. The addition of fiber alters diet viscosity, but our understanding of the effect of diet viscosity on nutrient digestibility is ...limited. This knowledge is necessary for improving dietary fiber utilization and when evaluating alternative feed ingredients. Thirty-six T-cannulated barrows (n = 6/treatment; initial BW = 26.5 ± 3.9 kg) were fed either corn-soybean meal (CSBM) basal diets or CSBM with 30% distillers dried grains with solubles as fiber source (CSBM+DDGS). The viscosity of diets were modified by using non-viscous cellulose (CEL), medium-viscosity carboxymethylcellulose (MCMC), or high-viscosity carboxymethylcellulose (HCMC) to assess viscosity effects on nutrient digestibility and intestinal physiology. After 29 d on diets, ileal digesta were collected to determine viscosity and apparent ileal digestibility (AID). Also, intestinal tissue and contents were harvested to determine morphometry, goblet cell quantitation, and digestive enzymatic activity. Data were analyzed using a linear mixed model with treatments as fixed effects and initial BW as a random effect. Results are shown in Table 1. No interactions were observed between viscosity and diets. Inclusion of MCMC and HCMC increased viscosity of supernatant and whole digesta compared with CEL. Increasing diet viscosity decreased AID of DM and CP in pigs fed MCMC and HCMC compared with pigs fed CEL, respectively. The AID of DM and CP were greater in CSBM than CSBM+DDGS. Inclusion of CMC increased crypt depth in the jejunum and goblet cell area in the ileum compared with pigs fed CEL regardless of basal diet fed. Digesta trypsin activity was not different among treatments, but inclusion of CMC increased amylase activity by 43% in jejunal digesta compared with CEL. The addition of DDGS reduced AID; however, viscosity affected intestinal morphology and function, suggesting that viscosity is the main characteristics of fiber affecting nutrient utilization of pigs.
Abstract
The objective was to evaluate the effects of maintaining cows in drylots vs pasture on beef cow performance. Spring-calving, Simmental × Angus cows (n = 108; 84 ± 11 d postpartum) were ...stratified by age, BW, BCS, calving date, and sex of calves and allotted to 6 groups. Groups were randomly assigned to 1 of 2 treatments for 110 d: drylot (DL) or pasture (PAST). Drylot cows were limit-fed a ration consisting of corn silage, dried distillers grains, hay, corn stalks, corn, and soybean hulls to meet protein and energy requirements. Cows on pasture were rotationally grazed and offered free-choice mineral. On d 0, cows were artificially inseminated (AI). On d 0, 53, and 110 (weaning), cow BW and BCS were measured. On d 54 milk production was estimated using the weigh-suckle-weigh technique. Data were analyzed using the MIXED procedure of SAS. All binary data were analyzed using the GLIMMIX procedure of SAS. On d 0 and 53, cow BW did not differ (P ≥ 0.73) between DL and PAST. On d 110, DL cows had 74 kg greater (P < 0.01) BW than PAST cows. The BCS did not differ (P ≥ 0.66) between treatments. There was no difference in milk production (P = 0.93); however, drylot cows tended (P = 0.10) to have reduced milk fat percentage and had reduced (P < 0.01) milk urea nitrogen. There was no difference (P ≥ 0.34) in AI or overall pregnancy rates between treatments. There was no difference in foot angle or claw set (P ≥ 0.17) of cows at any time point. There was also no difference (P = 0.17) in foot treatments between DL (39%) and PAST (4%). Housing cows in drylots compared to pasture increased BW, but did not affect BCS, milk production, and pregnancy rates.
Abstract
By 1900, research identified urea, ammonia, and protein as the basic components of N metabolism in ruminants. Energy and protein metabolic interactions were outlined, amino acids were ...individually recognized as constituents of protein molecules, and the concept of enzyme-catalyzed reactions was established. Research stations were publishing research results and feeding recommendations. By 2000, the National Research Council built on the work of Henry and Morrison to create and revise publications of nutrient requirements for various classes of ruminants. Use of surgically altered animals, isotopically labelled molecules, and standardized laboratory analyses created quantitative information on ingestion, digestion, absorption, and metabolism of N-containing compounds. Protein composition and structure as well as the role of protein turnover to determine the concentration of cellular proteins were elucidated. Hypothesis-driven, statistically valid experimental designs created quantitative information on protein and amino acid requirements. Methionine was identified as the likely first-limiting amino acid for several ruminant species and production states. The internet and the advent of international symposia provided links among researchers around the globe. Today, multidisciplinary research teams are needed to enlarge the data base, to describe proteomics and metabolomics, and to integrate “big data” into insightful and useful models. Those models currently use or estimate rates and daily amounts of ruminal (in)degradability of dietary protein, ammonia production, urea recycling, microbial protein synthesis, postruminal protein digestion, metabolic fecal nitrogen, and amino acid absorption and metabolism. They predict use of metabolizable amino acids for maintenance, milk yield, growth, and fetal growth. Directions of future research include integration of functional roles of amino acids into recommended dietary supply and requirements, and focus on solutions to challenges presented by climate change, (in)sustainability of livestock production, and changes in public perception of humans’ use of ruminants and other animals.
Abstract
A newly developed pectinase from Aspergillus terreus was compared with a commercially available pectinase at 600 IU/kg feed. Thirty (one-week postpartum) Damascus goats stratified by ...previous milk production, body weight and parity were divided into three experimental treatments. Does were fed a basal diet containing concentrates, orange silage, sugar beet pulp and wheat straw at 50:20:20:10, respectively with (a newly developed pectinase or commercial pectinase) or without a supplement (control treatment). No difference (P >0.05) was noted for feed intake but the newly developed pectinase increased (P < 0.01) nutrient digestibility, diet nutritive value and milk production efficiency more than the other treatments. Out of all the blood parameters, only serum glucose was affected by the treatments with highest (P = 0.025) value noted for the new pectinase. Similarly, the new pectinase increased daily milk production (P < 0.005) and the concentrations of milk components compared to the other two treatments. Additionally, pectinase (both the commercial and new) inclusion increased (P < 0.05) the concentrations of total conjugated linoleic acid and unsaturated/saturated fatty acids ratio, and decreased atherogenic index (P = 0.01) compared with control treatment. It is concluded that the supplementation of the diet of lactating goats with pectinase at 600 IU/kg feed will enhance feed digestion and milk production. The newly developed pectinase performed better than the commercial pectinase.
Abstract
We examined the effects of two direct-fed microbials (DFM) containing multiple microbial species and their fermentation products on ruminal fermentation, bacterial community and metabolome ...of beef steers. Nine rumen-cannulated Holstein steers were assigned to 3 treatments arranged in a 3 × 3 Latin square design with three 21-d periods. Dietary treatments were (1) CON (basal diet without additive), (2) PROB (basal diet plus 19 g/d of Commence), and (3) SYNB (basal diet plus 28 g/d of RX3). Commence is a blend of active S. cerevisiae, Enterococcus lactis, Bacillus subtilis, Enterococcus faecium, and L. casei, and their fermentation products. RX3 is a blend of active S. cerevisiae and the fermentation products of S. cerevisiae, Enterococcus lactis, Bacillus licheniformis, and Bacillus subtilis. Daily dry matter intake was calculated. On d 21 of each period, ruminal contents were sampled at 3, 6, 12, and 18 h after feeding for analysis of VFA, bacterial community via 16S rRNA sequencing, and metabolome via chemical isotope labeling liquid chromatography mass spectrometry. There was no effect on DMI. Compared to CON, supplementation of either PROB or SYNB increased or tended to increase (P ≤ 0.10) total VFA, propionate, and valerate concentrations. Compared to CON, PROB reduced (P ≤ 0.05) the relative abundance of Prevotella 1 and Prevotellaceae UCG-001, but increased those of Rikenellaceae RC9, Succinivibrionaceae UCG-001, Succiniclasticum, Ruminococcaceae UCG-014, and Ruminococcaceae UCG-002, whereas SYNB decreased (P ≤ 0.05) the relative abundance of Prevotella 1 and Prevotellaceae UCG-001, and increased those of Prevotella 7, Succinivibrio, Succiniclasticum, and Ruminococcaceae UCG-014. Metabolome analysis revealed that 8 ruminal metabolites, including some amino acids, were increased (P ≤ 0.05) by PROB, whereas no differences were found for SYNB. This study demonstrated that supplemental PROB or SYNB altered the ruminal bacterial community and metabolome differently to achieve a similar ruminal fermentation pattern.
Abstract
Our objective was to evaluate the effect of different sources of fatty acids (FA) fed to ewes during late gestation on offspring growth, carcass characteristics (CC), and glucose and insulin ...metabolism via glucose tolerance test (GTT). Fifty-four ewes (n = 18/treatment) were blocked by age, and BW; and within each block randomly assigned to one of three treatments fed from day 100 gestation until lambing. Treatments were: 1) no FA supplementation (CONT); or supplemented with 1% of lipid-enrich diet in 2) monounsaturated FA (MUFA); or 3) polyunsaturated FA (PUFA). At birth, all ewes and lambs were placed in a common pen and feed a common diet. At 60 days of age, lambs were weaned (d0), blocked by weight, and placed (3 lambs/pen; 6 pen/treatment; 3 pens of each sex) in a common diet until d56. Weight was measured on d0, d28, and d54; feed intake (FI) was measured daily. One lamb/pen was used on a GTT on d55, and another lamb/pen was used to determine CC (d56). Offspring data were analyzed as a randomized complete block design with a 2x2 factorial arrangement (FA*Sex; SAS 9.4). Treatments did not affect (P > 0.1) offspring FI, neither plasma glucose concentration (GTT). There was a FA*Sex interaction (P < 0. 05) for insulin. Males’ plasma insulin concentration increased as FA unsaturation degree increased during the GTT, the opposite happened with females. There was an interaction of FA*Sex*Day (P < 0.05) on lamb growth. On d0 MUFA females were heavier than MUFA males, but PUFA males were heavier than PUFA females; these differences disappeared at d28. Lambs born from PUFA had a heavier (P < 0. 05) hot carcass weight. In conclusion, dam’s FA supplementation modified offspring growth, insulin sensitivity, and HCW; these changes depended on the supplement FA unsaturation degree and offspring sex.
Abstract
Exogenous enzymes are routinely added to diets for non-ruminant animals, mainly to help enhance energy and nutrient utilization, thus contributing to efficient and sustainable production ...systems. Also, feed enzymes allow for effective utilization of non-traditional feedstuffs (e.g. co-products) in non-ruminant diets, with potential to mitigate feed cost. In addition to increased nutrient utilization, however, feed enzymes, through their impact on the gastrointestinal environment and microbial composition, can have a profound effect on indices of gut health and function. These effects may explain the reported reductions in medication costs and variability in animal performance and mortality rates observed with dietary enzyme supplementation. By acting on their target substrates, feed enzymes reduce the availability of non-digested substrates and in the case of carbohydrate-degrading enzymes can produce short-chain oligosaccharides with potential prebiotic effects. These changes are known to modulate the gut microbiome in favor of bacteria associated with a healthy gut, while reducing the population of pathogenic bacteria, which explains the reduced incidences of diarrhea that have been attributed to enzyme supplementation. Also, feed enzymes may reduce oxidative stress and enhance the functional capacity (e.g. maintaining barrier function) of the gastrointestinal tract. Feed enzymes by themselves may never be a single solution to mitigate gut health challenges in livestock production systems, but clearly there is a mounting body of evidence to support the role of feed enzymes in this regard. Therefore, their benefits will be maximized when used as part of an integrated solution approach for containing enteric pathogens of economic importance and eliminating the negative effects of dietary components with potential to compromise intestinal integrity.
Abstract
Our objectives were to determine the effects of feeding vitamin and mineral (VTM) and (or) energy (NRG) supplements to beef heifers during the first 83 days of gestation on concentrations of ...progesterone (P4), corpus luteum (CL) size, and fetal body measurements. Crossbred beef heifers (n = 35; initial BW = 359.5 ± 7.1 kg) were blocked by weight and assigned to one of four treatments (n = 8 or 9/group) in a 2 × 2 factorial arrangement with main effects of vitamin and mineral (NoVTM or VTM) and energy (NoNRG or NRG) supplements. A basal total mixed ration was fed once daily with VTM and NRG top-dressed. The VTM treatment (113 g•heifer-1•d-1) was initiated 71 to 148 d before AI. At AI, heifers were bred to a single sire, and NRG was initiated with target gains of 0.28 kg/d for NoNRG and 0.79 kg/d for NRG. Serum was collected on d 14, 28, 42, 56, 70, and 83 after AI and analyzed for. Gravid reproductive tracts were collected by ovariohysterectomy on d 83 ± 0.27 of gestation, and fetuses were dissected. An NRG × day interaction (P = 0.006) was observed for P4, with concentrations similar on d 14 to 56, a tendency (P = 0.09) for divergence at d 70, and greater (P = 0.002) concentrations for NRG on d 83 compared with NoNRG heifers. Furthermore, NRG heifers had greater CL weights than NoNRG (P = 0.003). Fetuses from NRG dams had greater (P = 0.009) femur weights than fetuses from NoNRG. Fetal liver weight was greater (P = 0.05) from dams fed VTM than NoVTM. Overall, providing NRG supplements during early gestation resulted in heavier CLs, that produced more P4, and greater fetal femur growth, whereas providing VTM supplements enhanced fetal liver growth.
Abstract
Ovarian follicle development and oocyte competence acquisition is dependent upon continuous interactions between the somatic cells and the oocyte. Interactions between these cell types ...include bidirectional paracrine signaling and the exchange of small molecules, such and amino acids and cyclic nucleotides, through gap junctions located at the end of transzonal projections (TZPs). In the last decade, additional mechanisms of cell-to-cell interactions within the ovarian follicle were described. These mechanisms include the movement of small extracellular vesicles (EVs) within the follicular fluid and the delivery of its cargo to target cells; and the exchange of large molecules transiting from the cumulus cells to the oocytes via transzonal projections. Here, I will describe the investigations about these novel communication systems in the bovine ovarian follicle. The topics will include the content of EVs transiting in the bovine follicular fluid and its role regulating signaling pathways associated with oocyte competence, and the movement of large molecules from cumulus cell to the oocyte such as messenger RNAs and fatty acids. Finally, dysregulations of such communications mechanisms under in vitro culture conditions will also be reviewed. Emphasis will be given on the lipid metabolism in the cumulus-oocyte complex and lipid accumulation mediated by transzonal projections and fatty acid binding proteins in oocytes undergoing in vitro maturation.
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