Abstract Beef-dairy cross calves have increased prevalence of liver abscesses at slaughter compared to beef calves, which may be due to early feeding management strategies that predispose these animals to gastrointestinal insult during the finishing phase. The objective of this study was to compare different concentrations of starch in calf starter on carryover growth performance and gastrointestinal function in beef-dairy cross calves during finishing transition. During the hutch phase, castrated male beef-dairy cross calves (N = 10) were randomly allocated to one of two calf starters with high (44%) or low (24%) starch (n = 5/treatment) and were fed a common growing diet for 130 days following removal from the hutch. During the finishing transition, all animals (initial BW = 277 kg) received the same diets, which included a starter diet, two step up diets, and a finishing diet, increasing in starch concentration with each diet. Calves were weighed periodically throughout the 28-day finishing period then slaughtered, and pH of rumen, duodenum, jejunum, ileum, and colon contents obtained. Data on BW, DMI, G:F, and pH were analyzed using linear models (R v.4.5.1) with fixed effects (treatment, diet, day, GI segment, and interactions), and random effect of calf when appropriate. ADG (1.68 and 1.92 ± 0.11 kg/d) and G: F (0.247 and 0.286 ± 0.0183 kg/kg) revealed no evidence of difference (P 0.05) between high and low starch groups, respectively. There was no evidence of difference between treatments on DMI (P = 0.86), although there was a step-up diet effect on DMI where cattle consumed less (P 0.001) DMI while on step-up diet 2 compared to other diets. The jejunum exhibited a lower pH than the ileum and colon (P 0.05) for both treatments, while the duodenum was more acidic than the ileum (P 0.05) for the low starch group only. There were no other significant differences observed between the other sections (P 0.05). The rumen pH was 6.17 and 6.75 for high and low starch groups, respectively, but there was no evidence of difference between groups (P = 0.34). In conclusion, starch inclusion level of calf starter diet had no carryover effects on feed intake, growth, or gastrointestinal function during the finishing transition.
Rivas et al. (2026) studied this question.