357 The Effects of Colostrum Consumption and Feed Restriction on Performance, Energy Balance, and Behavior in Unweaned Male Holstein Calves Being Marketed and Transported

Abstract

Abstract Male Holstein calves (n = 80; 42.7 ± 1.44 kg and 14.2 ± 0.81 days of age) were used to evaluate the effects of colostrum consumption and feed restriction on performance, energy balance (serum concentration of BHB and NEFA), and behavior on calves marketed and transported during 19h. Well-colostrated (WC) calves received 4L of colostrum within the first 2h after birth and 2L of colostrum in the next 3 feedings and poor-colostrated (PC) calves received 2L of colostrum within the first 2h after birth. At approximately 14 d of age, calves were subjected to an assembly center simulation (ACS, d-4 to d-1) before a 19h-transport (d0) where they were fed 4L of milk replacer (MR)/d (moderate restriction; MO) or 4L of a rehydration solution/d (severe restriction; SV). After the ACS, treatments were: WCMO, WCSV, PCMO, PCSV and a control group (WCCT) with ad-libitum access to concentrate and not transported. From d1 to d7, all calves were fed the same diet (4L/d of MR and ad-libitum access to concentrate, straw, and water). Data were analyzed using mixed models with repeated measures. There was a time by treatment interaction (P< 0.01) for NEFA and BHB concentrations before transport being greater for the WCSV compared with PCSV calves. After the ACS, BW was reduced (P< 0.01) for the WCSV and PCSV calves compared with the WCCT, WCMO and PCMO calves. After transportation, a time by treatment interaction (P< 0.01) was observed in concentrate intake recovery being lesser for the PCSV and PCMO; it took 4 days for those calves to recover concentrate intake to the same extent that WCCT, WCMO, and PCMO. During the ACS, PCSV calves showed greater (P=0.05) standing times compared with the remaining calves. Colostrum consumption and the degree of feed restriction affect physiological, performance, and behavior responses in calves before and after transportation.