ABSTRACT The objective of this study was to investigate the potential carryover effect of narasin (NAR) supplementation during the backgrounding phase on subsequent feedlot performance and gastrointestinal morphometrics of finishing Nellore bulls. Ninety-six bulls were used in a 2 × 2 factorial design, evaluating conditional NAR supplementation on the backgrounding phase (control [CON] or NAR) and finishing supplementation (sodium monensin [MON] or NAR), resulting in four treatments as follows: 1) CON+MON, 2) CON+NAR, 3) NAR+MON, and 4) NAR+NAR. During the […]

ABSTRACT This study evaluated the association of stearoyl-CoA desaturase (SCD) and fatty acid-binding protein 3 (FABP3) gene polymorphisms with carcass and meat quality traits in Aberdeen Angus bulls. Two hundred seventy-four Angus bulls were genotyped using PCR-RFLP and Sanger sequencing. Next, the association of SCD and FABP3 genetic variants with traits such as live weight, average daily weight gain, carcass weight (both hot and cold), dressing percentage, carcass length, back fat thickness, carcass color score, pH, and marbling score was […]

ABSTRACT This study evaluated the substitution of corn grain with white oat grain in finishing yearling bulls (initial weight of 259.4±31.7 kg and 18.0±0.2 months of age). The experimental design was completely randomized. The substitution levels of corn grain for white oat grain were 0, 25, 50, 75, and 100%. Diets comprised 85% of grains + 15% of a protein-vitamin-mineral pelleted supplement. The adaptation program consisted of ad libitum feeding of five diets over the adaptation period of 14 days, […]

ABSTRACT This study was conducted to evaluate the relationship among digestibility, residual feed intake (RFI), and enteric methane emission in growing Nellore cattle (Bos indicus) divergently classified based on RFI phenotype and breeding value (EBV-RFI). Animals (n = 122) subjected to performance testing (forage:concentrate ratio of 60:40) in two test groups were classified based on RFI. A sample of 80 animals classified as low (−0.748±0.076 kg DM/day) or high (0.775±0.075 kg DM/day) RFI was evaluated regarding feed compounds digestibility, fecal […]

ABSTRACT Our objective was to compare performance and carcass characteristics of backgrounding steers grazing poor quality pasture, receiving energy or protein supplements during summer, and on subsequent finishing period. Sixty Hereford steers (14 months; 348±33 kg body weight [BW]) were blocked by BW and randomly assigned to one of three treatments (n = 20 per treatment): control (non-supplemented) and supplemented at 0.8% BW with whole grain of corn (CS) or lupin bean (LS) (phase I; 77 days). Over the following […]

ABSTRACT The objective was to explore publications on the effects of genotype × environment interaction (GEI) in livestock farming. The dataset used for this analysis came from the Web of Science (WOS) database, and the search was carried out from the first article identified in the WOS database until the search date (August 17, 2023). A set of minimum parameters was defined, and then the data was processed using the VOSviewer® software. To generate visual representations in VOSviewer, fractional counting […]

ABSTRACT We investigated the impact of weaning at 30, 75, and 180 days of age on performance, body measurements, and rumen development (using the β-hydroxybutyrate biomarker) of beef calves until 190 days of age. A total of 64 Brangus calves were assigned to three treatments: hyper-early (W30), weaned at 32±0.89 days of age (n = 22, 10 males and 12 females); early (W75), weaned at 77±0.95 days of age (n = 20, 12 males and eight females); and conventional (W180), […]

ABSTRACT The main objective of this study was to evaluate the effects of phenotypic, genotypic, and auction characteristics that may influence the selling prices of bulls. Data from 1,540 Braford and 1,179 Brangus bulls sold at auctions in the state of Rio Grande do Sul, Brazil, were collected and evaluated individually. Body condition score (BCS), muscularity, frame, foreskin size, presence or absence of horns, and data regarding the auction such as name/venue, event edition, forms of payment, among others, were […]

ABSTRACT The objective of this study was to evaluate the potential of improving the economic value of integrated crop-livestock systems (ICLS) compared to conventional systems specialized in monoculture. The experimental area was 16.02 ha, divided into 18 paddocks of 0.89 ha each, organized in a randomized block design, with three replicates and six models of production systems: crop system [corn ( Zea mays ) grain production], livestock system (beef cattle under grazing conditions), and four ICLS, identified as: ICLS-1, corn […]

ABSTRACT The objective of this study was to evaluate the effect of intronic single nucleotide polymorphisms (SNP) on temperament traits in a Brahman cattle population. The SNP located in CACNG4, EXOC4, NRXN3, and SLC9A4 candidate genes were genotyped in 250 animals with temperament records of exit velocity, pen score, and temperament score. Rs3423464051:G>A in the CACNG4 gene was associated with exit velocity and temperament score. An in silico analysis of the five intronic SNP showed that alternative alleles of CACNG4-rs3423464051, […]