Abstract
Beef calves express behaviors such as walking and vocalizing to a greater extend during weaning. These behaviors increase production costs due to compromised calf growth, health, and welfare. Oxytocin treatment reduces anxious behaviors and attenuates the HPA axis, thus the objective of this experiment was to evaluate the effects of oxytocin on calf growth, cortisol, and distance walked at weaning. A total of 20 Angus x Simmental heifer calves were randomly allotted to each treatment group (n = 10), intranasal oxytocin or saline (OXT, CON). All calves were administered the respective intranasal treatment at weaning (day 0), and then placed in the same pasture. Calves were weighed and blood sampled on days 0, 1, 7, and 14. Blood samples were used to quantify non-esterified fatty acids (NEFA), β-hydroxybutyrate, and cortisol. Each heifer was fitted with a global positioning system collar that recorded calf location every 10 seconds for 16 h on days 0, 7, and 14. To further evaluate calf behavior, observations were made on days 0, 7, and 14 using instantaneous scan sampling from 0730 to 0830, 1200 to 1300, and 1700 to 1800 h. Data were analyzed using a completely randomized design with repeated measures model (SAS 9.4). Providing calves with intranasal oxytocin on the day of weaning did not have an effect on the distance walked, observed behavior, body weight, β-hydroxybutyrate, or cortisol concentrations, however, there was a day effect (P < 0.05) for these variables. Intranasal oxytocin treatment did affect NEFA concentrations, as calves in the CON group had greater NEFA concentrations on day 1 compared with calves in the OXT group (P < 0.05). These data imply that intranasal oxytocin could have the capacity to decrease mobilization of NEFA, but this change was not enough to affect body weight 14 days after weaning.
51 Intranasal oxytocin improves plasma non-esterified fatty acids but not distance walked or cortisol concentrations at weaning
