Effect of quantitative feed restriction and sex class on sheep skin quality.

The aim was to evaluate the quality of the sheep skin of different sex classes submitted to different levels of feed restriction. Sheep without defined racial pattern of different sex classes (15 non-castrated males, 15 castrated males and 15 females), with initial body weight of 18.1 ± 0.

Regression models from portable NIR spectra for predicting the carcass traits and meat quality of beef cattle.

The aims of this study were to predict carcass and meat traits, as well as the chemical composition of the 9th to 11th rib sections of beef cattle from portable NIR spectra. The 9th to 11th rib section was obtained from 60 Nellore bulls and cull cows. NIR spectra were acquired at: P1 -center of Longissimus muscle; and P2 -subcutaneous fat cap.

Characteristics of intramuscular collagen in calf-fed Nellore bulls and steers throughout the finishing phase.

This study evaluated collagen solubility and gene expression of biomarkers for intramuscular collagen (IMCT) deposition and remodeling in the Longissimus muscle of bulls and steers through the finishing phase. Thirty-six Nellore calves were used (18 bulls and 18 steers), and six of each sexual condition were randomly assigned to be harvested at 0, 100, or 200 days on feed (DOF) to evaluate collagen characteristics in different time points throughout the finishing phase. Bulls showed a greater collagen solubility than steers (P = 0.

Assessing dual-energy X-ray absorptiometry prediction of intramuscular fat content in beef longissimus steaks.

This study assessed the capability of dual-energy X-ray absorptiometry (DEXA) to predict intramuscular fat (IMF) content of beef longissimus steaks against chemical IMF as the gold standard. DEXA performance of fat% prediction was assessed using a leave-one-out cross validation method among Angus and Nellore steaks, which generated a chemical fat% range of 14.05-36.

Strategic administration of an appeasing substance to improve performance and physiological responses of Bos indicus feedlot cattle.

This study was designed to evaluate the timing of administration of the bovine appeasing substance (BAS) on performance and physiological responses of Bos indicus feedlot cattle. Nellore bulls (n = 100) were ranked by initial body weight (BW; 341 ± 18.5 kg) and assigned to receive BAS (n = 50) or placebo (CON; n = 50) on day -2 of the experiment.

Intramuscular collagen characteristics and expression of related genes in skeletal muscle of cull cows receiving a high-energy diet.

We aimed to investigate differences in the synthesis and metabolism of intramuscular collagen in the Longissimus thoracis (LT) muscle between heifers and cull-cows fed high-energy diet. Ten cull-cows, (74.9 ± 3.

California net energy system for .

The California net energy system (CNES) was the reference for the development of most energy requirement systems worldwide, such as Nutrient Requirements of Beef Cattle (NASEM, Nutrient requirements of beef cattle, 8th Revised ed, 2016) and Brazilian Nutrient Requirements of Zebu and Crossbred Cattle (Valadares Filho, S. C., L.

Proteomic analysis reveals changes in energy metabolism of skeletal muscle in beef cattle supplemented with vitamin A.

Background: Vitamin A has been reported as a factor influencing marbling deposition in meat from animals. Although the mechanisms by which vitamin A regulates lipid metabolism in mature adipocytes are already well-established, information regarding molecular mechanisms underlying the effects of vitamin A on the regulation of intramuscular fat deposition in beef cattle still remains limited. The present study aimed to assess the molecular mechanisms involved in the intramuscular fat deposition in beef cattle supplemented with vitamin A during the fattening phase using a proteomic approach.

Explaining meat quality of bulls and steers by differential proteome and phosphoproteome analysis of skeletal muscle.

The objective of this study was to evaluate the differential proteome and phosphoproteome between bulls and steers during conversion of muscle to meat, as well as after 14 days of aging. Twelve male Nellore (Bos taurus indicus) calves were used, and six calves were randomly selected for surgical castration. Calves were fed the same diet and were harvested after 230 days on feed.

Total nutrient digestibility and small intestine starch digestion in Nellore and Angus young bulls fed a whole shelled corn diet.

Eighteen Nellore and 18 Angus young bulls with BW of 381 ± 12 kg were randomly assigned into two feeding groups (whole shelled corn [WSC] or ground corn with silage [GC]) to evaluate the interaction of breed and diet on total nutrient digestibility, pancreatic α-amylase, and maltase activity and SLC5A1expression in the small intestine. Experimental diets (DM basis) included (a) a diet containing 30% corn silage and 70% GC and soya bean meal-based concentrate and (b) a diet containing 85% WSC and 15% of a soya bean meal- and mineral-based pelleted supplement. The treatments were Nellore fed GC diet; Nellore fed WSC diet; Angus fed GC diet; and Angus fed WSC diet.

Subspecies and diet affect the expression of genes involved in lipid metabolism and chemical composition of muscle in beef cattle.

Fourteen Nellore and 14 Angus young bulls with BW of 381±11.8kg were randomly assigned into 2 feeding groups (whole shelled corn without forage (WSC) or corn silage and ground corn (GC)) to evaluate chemical composition and expression of genes involved in lipid metabolism in the longissimus thoracis (LT). We hypothesized that bulls fed the WSC diet have greater amounts of intramuscular fat and Angus have higher expression levels of PPAR and SREBF.

Effect of post-weaning growth rate on carcass traits and meat quality of Nellore cattle.

This study evaluated the effects of growth rate during post-weaning growing phase on carcass traits and beef quality. Thirty-four Nellore young bulls were randomly assigned to one of three treatments: LOW, MEDIUM or HIGH growth rate during post-weaning growing phase followed by high growth rate in the finishing phase. The growth rate affected (P<0.

Energy and protein requirements of young Holstein calves in tropical condition.

Our objective was to estimate the energy and protein requirements of Holstein young calves up to 87 days old. Forty-two Holstein calves aged 4 days were used. From these, ten were randomly selected and slaughtered to compose the baseline slaughter (BS) group.

Net requirements of calcium, phosphorus, magnesium, and sulphur for growth of non-descript breed hair lambs of different sex classes in the Brazilian semiarid conditions.

The aim of this study was to determine the net requirements of calcium (Ca), phosphorus (P), magnesium (Mg), and sulphur (S) for weight gain of non-descript breed hair lambs (NDBL) of different sex classes reared under Brazilian semiarid conditions. Sixty NDBL (20 intact males, 20 castrated males, and 20 females), with an average initial body weight of 18.1 ± 0.

Molecular Factors Underlying the Deposition of Intramuscular Fat and Collagen in Skeletal Muscle of Nellore and Angus Cattle.

Studies have shown that intramuscular adipogenesis and fibrogenesis may concomitantly occur in skeletal muscle of beef cattle. Thus, we hypothesized that the discrepancy of intramuscular fat content in beef from Nellore and Angus was associated with differences in intramuscular adipogenesis and fibrogenesis during the finishing phase. To test our hypothesis, longissimus muscle samples of Nellore (n = 6; BW = 372.

Indirect methods for predicting body composition of Boer crossbreds and indigenous goats from the Brazilian semiarid.

The aim of this study was to evaluate the correlation and to develop regression equations between the body composition obtained by the comparative slaughter and the neck composition and the ultrasound ribeye area (REAu) in goats from the Brazilian semiarid region. Forty-five intact male goats from three genetic groups were used: 15 Canindé, 15 Moxotó, and 15 F1 Boer x non-descript breed. Animals were randomly assigned to three feeding levels (ad libitum, 25 and 50% restriction) aimed to result in different slaughter weights and body composition, to fit the regression equations.

Achieving body weight adjustments for feeding status and pregnant or non-pregnant condition in beef cows.

Background: Beef cows herd accounts for 70% of the total energy used in the beef production system. However, there are still limited studies regarding improvement of production efficiency in this category, mainly in developing countries and in tropical areas. One of the limiting factors is the difficulty to obtain reliable estimates of weight variation in mature cows.

Carcass and non-carcass component yields of crossbred Boer and Brazilian semiarid indigenous goats subjected to different feeding levels.

The effect of different feeding levels (ad libitum, 25 and 50 % restriction) and genotypes (½ Boer × ½ nondescript breed goats, Canindé, and Moxotó) on carcass quantitative characteristics and non-carcass components (NCC) were evaluated. Forty-five intact male goats were distributed in a 3 × 3 factorial design with five replicates. There was no effect of genotype on carcass weights and yields and retail cuts weights and yields (P > 0.

Mango tree pruning hay in substitution of elephant grass in cattle diet.

This experiment was conducted to evaluate the effect of different levels of substitution (0, 33.3, 66.7, and 100 %) of elephant grass by hay of mango tree pruning (HMTP) on intake and digestibility in cattle and on the in vitro gas production.

Lipids in the diet and the fatty acid profile in beef: a review and recent patents on the topic.

The objective of this review is to report how the use of lipid sources in diets for ruminants can affect the fatty acid profile of beef. In addition, recent patents that can be utilized to alter the fatty acid profile in the meat, or which concern the synthesis of conjugated fatty acids will be reviewed. The industrial production of conjugated linoleic acid (CLA) has already started and the commercial products present isomers cis-9, trans-11; trans-9, cis-11; and trans-10, cis-12.