PSVII-26 - Effects of an electrolyte drinking solution on performance and physiological responses of preconditioning beef calves

Abstract: Weaning and transport are the major stressor events for beef cattle production. Strategies to mitigate weaning stress responses and promote quick recovery of homeostasis are always warranted to improve welfare and productivity of beef cattle. This study evaluated the effects of an electrolyte drinking solution on the performance and physiological responses of pre-conditioning beef calves. Forty Angus × Hereford steers [230.4 ± 4.8 kg body weight (BW), 195 ± 30 days of age] were sorted into 20 pens (2 calves/pen) immediately after weaning for a 45-d preconditioning period. Pens were randomly assigned to two treatments: 1) control: water; 2) electrolyte solution: water and electrolyte drinking solution on one additional trough per pen. A total of 10% of the estimated daily water intake of calves was fortified with the electrolyte solution on the ratio of 31.6 g/L of water. The electrolyte composition contained calcium, phosphorus, salt, magnesium, potassium, and a mix of carbohydrates. Treatments were provided from d 1 to 14, and thereafter electrolyte supplementation was ceased. Assigning weaning as day 0, calf BW was recorded and blood samples were collected via jugular vein puncture into commercial heparinized vacuum tubes on d 0, 1, 3, 7, 14, 21, 44 of the experiment. Plasma samples were analyzed for haptoglobin, ceruloplasmin and cortisol. Variables were analyzed considering pen as the experimental unit and pen(treatment) as a random effect. Blood parameters were evaluated as repeated measurements and effects of treatment, day, and treatment and day interaction were analyzed with the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC, USA). Significance was set at P ≤ 0.05. Calves consumed 700 mL of electrolyte solution daily which consisted of 20% of the offered. No effects (P = 0.61) were observed on ADG (0.82 kg, SEM: 0.050) or final body weight (P = 0.81; 267 kg SEM: 5.36). No differences in cortisol (P = 0.64; 2.30 ng/mL SEM: 0.147), ceruloplasmin (P = 0.29; 26.9 mg/mL SEM: 0.659) and haptoglobin (P = 0.57; 0.64 µg/mL SEM: 0.029) concentrations were observed. Electrolyte solution supplementation during preconditioning did not improve performance or influenced acute response markers of beef calves.