Impacts of residual feed intake and pre-natal diet on reproductive potential of bulls

Abstract

Our objective was to determine effects of genetic potential for residual feed intake (RFI) and pre-natal diet on post-natal growth and reproductive development of bulls. Twenty-five bull calves with a divergent potential for RFI were produced by mating purebred Angus heifers (60) categorised as high or low RFI and inseminated with semen from high or low RFI bulls. From 30 to 150 days of gestation, half the heifers (balanced for RFI across treatments) in each RFI category were fed to gain 0.7 or 0.5 kg/day (~100% and 75% of recommended feed intake; designated normal- and low-diet, respectively). Birthweights of bull calves (n = 25) did not differ significantly among treatment groups (P ≥ 0.1). However, there was a tendency (P < 0.1) for a maternal diet*time interaction for bull weights, with bulls from low pre-natal diet fed heifers growing faster between 10 and 16 months of age than bulls from normal pre-natal diet fed heifers. Furthermore, high-RFI bulls had a larger scrotal circumference (P < 0.01) and attained puberty (P < 0.05) earlier than low-RFI bulls. Other testes measures, including paired testes volume, epididymal sperm reserves, daily sperm production and total sperm production, were not significantly different among treatment groups (P ≥ 0.1). High RFI bulls tended (P < 0.1) to have better average sperm motility than low RFI bulls. However, sperm morphology, viability and chromatin damage were not different (P ≥ 0.1). In summary, young beef bulls with low RFI had smaller testis, delayed onset of puberty (~1.7 months) and tended to exhibit lower progressive motility compared with high RFI bulls. Pre-natal diet had no direct influence on male reproductive development, nor did it interact with RFI of bulls.

The Bovine Metabolome

“…Twenty-six purebred Angus bulls raised on the Roy Berg, University of Alberta Kinsella Ranch (Kinsella, AB, Canada), were used in this study. After weaning, the bulls were fed and managed according to industry standards for feedlot production of finished cattle in Alberta until they reached approximately 17 months of age [68]. The bulls were then slaughtered at the Agriculture and Agri-Food Canada (AAFC)-Lacombe Research Centre abattoir over a period of four days to collect the target tissues [68].…”

Exploring Biological Impacts of Prenatal Nutrition and Selection for Residual Feed Intake on Beef Cattle Using Omics Technologies: A Review

“…As well, a greater number of progeny per sire was seen for LRFI bulls in a multi-sire natural mating experiment ( Wang et al, 2012 ). In contrast, other studies found that LRFI bulls had a smaller scrotal circumference ( Johnson et al, 2019 ), decreased sperm motility ( Wang et al, 2012 ; Awda et al, 2013 ; Johnson et al, 2019 ), decreased progressive sperm motility, increased abundance of tail abnormalities, and delayed sexual maturity ( Fontoura et al, 2016 ; Montanholi et al, 2016 ). Moreover, when RFI was adjusted for backfat thickness, LRFIfat bulls displayed lower sperm motility, decreased progressive sperm motility, as well as a smaller scrotal circumference ( Awda et al, 2013 ).…”

“…Because no net increase in muscle fibre numbers occurs after birth, nutrient insults during early gestation may change nutrient partitioning to essential organs rather than skeletal muscle ( Greenwood et al, 2000 ; Zhu et al, 2006 ; Long et al, 2009 ; Du et al, 2010 ; Funston et al, 2010 ; Du et al, 2011 ). Several studies have shown that calves born from dams that were nutritionally restricted during early-to mid-gestation and then re-alimented before parturition had similar ratios of weight gain to feed intake ( Long et al, 2009 ; Long et al, 2012 ; Johnson et al, 2019 ). However, there is some evidence for increased weight gain between 10 and 16 months of age compared to their normally fed control groups ( Johnson et al, 2019 ).…”

“…Several studies have shown that calves born from dams that were nutritionally restricted during early-to mid-gestation and then re-alimented before parturition had similar ratios of weight gain to feed intake ( Long et al, 2009 ; Long et al, 2012 ; Johnson et al, 2019 ). However, there is some evidence for increased weight gain between 10 and 16 months of age compared to their normally fed control groups ( Johnson et al, 2019 ).…”

“…These effects were observed when dams were nutritionally restricted during early-to mid-gestation and then re-alimented thereafter. In both sheep and cattle, there was no significant effect on reproductive development and adult reproductive function in rams or bull progeny, when ewes or heifers were nutritionally restricted during early-to mid-gestation and re-alimented thereafter ( Rae et al, 2002a ; Rae et al, 2002b ; Johnson et al, 2019 ). However, delayed prostate development has been observed in male rat pup progeny, when Wistar rat dams were fed a protein-restricted diet throughout the entire gestational period ( Rinaldi et al, 2013 ).…”