The objective of this study was to evaluate the addition of cane molasses during a 60 day dry period on performance and metabolism of Holstein cows during prepartum and postpartum periods. For experiment 1, 26 primiparous and 28 multiparous cows were used. Upon freshening, all cows were offered a common lactation diet. For experiment 2, six multiparous cows fitted with rumen cannulas were used to measure performance and metabolism, following the same protocol as experiment 1. Ruminal propionate increased by 10% during both prepartum and postpartum periods; however, papillae area was greater for cows not fed molasses, and volatile fatty acids (VFA) absorption from the rumen was not increased, resulting in similar glucagon-like-peptide-2 receptor (GLP-2R) density. The improved dry matter intake, when molasses was added into prepartum diets, translated into increased milk yield and energy-corrected milk (ECM) in Experiment 1 only for multiparous cows. For experiment 2, the improvement on milk performance was also observed, where cows fed molasses had 18.5% greater ECM production. Feeding molasses during a 60 day dry period positively influenced transition cow performance, and it was not accompanied by changes in rumen morphometrics; however, this indicates enhanced adaptation by the rumen epithelium based on similar capabilities for VFA absorption.

The objective of this study was to evaluate the effect of either a limited forage intake or concentrate supplementation prior to the adaptation to high-concentrate diets on dry matter intake, ruminal pH, bacteria, and protozoa of Nellore cattle. The experiment was designed as a two 3×3 Latin square, and six cannulated Nellore steers were used. Each experimental period was composed by three feeding phases: pre-adaptation (14 days), adaptation (12 days), and finishing (seven days) diet, in a total of [...] ABSTRACT The objective of this study was to evaluate the effect of either a limited forage intake or concentrate supplementation prior to the adaptation to high-concentrate diets on dry matter intake, ruminal pH, bacteria, and protozoa of Nellore cattle. The experiment was designed as a two 3×3 Latin square, and six cannulated Nellore steers were used. Each experimental period was composed by three feeding phases: pre-adaptation (14 days), adaptation (12 days), and finishing (seven days) diet, in a total of

This study evaluates the effects of a proprietary tannin blend (BX), supplemented with or without sodium monensin (MON), on beef cattle performance, carcass traits, and health. Steers (n = 2986; initial shrunk body weight (SBW) 254 ± 9.2 kg) were allocated into 48 pens (61–62 steers/pen; 12 pens/treatment) fed for 230 d. Treatments included: (1) no feed additives (CTL); (2) BX (7.95 g/animal daily); (3) MON + Tylosin phosphate (TYL; 437.52 mg MON/animal daily + 80 mg TYL/animal daily); or (4) MON + BX (437.52 mg MON/animal daily + 7.95 g BX/animal daily). Data were analyzed in R 4.2.1 using a randomized block design with pen as the experimental unit. Dry matter intake was lower (p < 0.001) in MON + TYL and MON + BX than in CTL. Steers fed MON + BX had greater carcass-adjusted final SBW (p = 0.002), average daily gain (p = 0.002), fat thickness (p = 0.035), and marbling score (p = 0.046) than BX. Feed conversion improved in MON + TYL and MON + BX (p < 0.001). CLT and BX had higher (p < 0.001) liver abscess prevalence compared to MON + BX and MON + TYL. The addition of BX did not improve the parameters measured. Steers fed MON + BX showed reduced liver abscesses and similar feed efficiency compared to MON + TYL.

Liver abscesses are a significant concern in cattle feeding, linked to visceral condemnation and carcass trimming; however, the molecular mechanism of development and progression of liver abscesses is unknown. This study aimed to evaluate the hepatic transcriptomic profile, immunohistochemistry, and IGF-I circulation in beef × dairy (Angus × Holstein) steers with and without liver abscesses. Samples were collected from twelve steers (final body weight of 719 ± 5.8 kg) originating from the same feedlot and were selected based on liver scores at harvest. The animals were divided into abscessed (n = 6) and healthy livers (n = 6). Blood samples were used to measure circulating insulin-like growth factor I (IGF-I) levels using an ELISA kit. Liver samples were divided into two portions; one portion was used for immunohistochemistry (IHC) to identify IGF-I receptor (IGF-IR) abundance, while the second portion was used for RNA extraction, library preparation, and sequencing (Illumina NovaSeq 6000 platform). Differentially expressed genes (DEGs) were identified with the DESeq2 R package, using an adjusted p-value ≤ 0.05 and fold change > 1.5. Sera IGF-I was not affected by liver condition; however, IGF-IR abundance was up-regulated in abscessed livers. A total of 568 DEGs were identified, with 372 up-regulated and 196 down-regulated in abscessed livers. Notably, the most highly up-regulated genes were FGF23, NXPH4, and CYP7A1, while EPHA6, CD70, and INHBA showed the most significant downregulation. Protein-protein interaction (PPI) network analysis identified THBS1 and COL1A2 as significant hub genes. The DEGs showed enrichment in biological processes related to angiogenesis, cell migration, adhesion, and extracellular matrix organization. Pathway analysis indicated activation in signaling pathways, including hepatic fibrosis, interleukin, and IGF-I signaling. These findings reveal candidate genes and pathways linked to inflammatory responses and tissue remodeling, offering valuable evidence that enhances our understanding of the progression of liver abscesses in cattle.