Milk yield, composition and immune status of dairy goats and respective goat kids fed diets with selenium and vitamin E supplementation

Abstract

This study was carried out to examine the effects of including selenium (Se) and vitamin E (vitE) in diets for goats and their kids on milk yield and composition, and immune status. Twenty-one 1/2 Saanen x Pardo Alpine goat kids (average body weight of 3.70 ± 0.64 kg) were born from fifteen female Saanen goats (non-lactating and primiparous) with an average age of six years and an average initial live weight of 70 ± 10 kg, which had previously been synchronized with the OvSynch protocol. Animals were allocated at random to the treatments in a completely randomized experimental design, with five replicates per diet for goats and seven replicates, for goat kids. Animals were randomly assigned into three groups in the following diets: CON: control basal diet; Se: inclusion of 3.2 mg of Se/kg DM; SevitE: inclusion of 3.2 mg Se / kg DM and 1145 IU / day vitE/kg DM. Milk yield and composition of goats were evaluated only considering the average production of the period, whereas Se in serum, milk and total plasma antioxidant capacity and phagocytosis intensity data were evaluated by time repeated measures. Goats fed CON diet showed higher total dry extract levels in milk than those fed Se diet (P< 0.05). An interaction between diet and time was observed for serum Se concentration in goats (P < 0.01). The Se concentration in milk was higher for goats fed the Se and SevitE than animals fed the CON (P = 0.01). There was only a time effect (P = 0.04) for Se concentrations in milk, and vitE in serum (P < 0.01) and milk (P < 0.01) and TAS (P < 0.01). The concentrations of Se in the blood of goat kids fed the SevitE, and Se diets were higher than animals fed the CON diet (P < 0.01). Diets influenced the Se concentration and phagocytosis intensity, while a time effect was observed on phagocytosis intensity (P < 0.05). A week effect was observed for phagocytosis of E. coli in goats (P = 0.01). For goat kids, a diet effect was observed for phagocytosis of E. coli (P = 0.01) and only the percentage of polymorphonuclear leukocytes was not influenced by diets (P = 0.95). The inclusion of Se and vitE or their combination reduces oxidative stress without influencing oxidative stress in neonates fed with milk from goats supplemented with selenium and vitamin E in their diets.