Metaphylactic effect of diphenyl diselenide (PhSe)₂ on the health of beef female calves subjected to conventional weaning

The objective of this study was to evaluate the impact of diphenyl diselenide (PhSe)(2) on the average daily gain, biochemical parameters, and oxidative status of beef calves subjected to conventional weaning. Thirty female calves, aged six months and weighing 152.42 +/- 13.75 kg, were used. The experiment was laid out in a completely randomized design, with the experimental units divided into three groups: control group (n=10): 2 mL of NaCl solution; dimethyl sulfoxide group (n=10): 2 mL of dimethyl sulfoxide; and diphenyl diselenide group (n=10): 3 mu mol kg(-1) of (PhSe)(2) diluted in 2 mL of dimethyl sulfoxide. Collections and evaluations were conducted at the following time points: -28 (baseline, T1) and -14 (T2) days before weaning; on the initial day of weaning (day 0, T3); and 14 ( T4) and 28 (T5) days after weaning. Treatments at T1, T2, and T3 were administered subcutaneously. All animals were subjected to similar handling and feeding conditions throughout the experiment, with free access to water. The assessed parameters included average daily gain, total protein, albumin, globulin, albumin:globulin ratio, reduced glutathione, thiobarbituric acid reactive substances, and total antioxidant capacity determined by the ferric reducing antioxidant power. Among the evaluated parameters, significant differences (P<0.05) were observed in average daily gain according to time points; albumin according to treatments, time points, and treatment x time interaction; globulins according to time points and treatment x time interaction; albumin:globulin ratio according to time points and treatment x time interaction; reduced glutathione according to time points and treatment x time interaction; and ferric reducing antioxidant potential according to time points. The administration of diphenyl diselenide to beef female calves resulted in an increase in albumin, globulin, albumin:globulin ratio, and reduced glutathione during conventional weaning. The beneficial effect of diphenyl diselenide was verified by the treatment x time interactions. These results demonstrate that diphenyl diselenide serves as an alternative to traditional sources of organic selenium, and its use mitigates the challenges faced by beef calves during conventional weaning.