The effect of intra-ruminal selenium pellets on growth rate, lactation and reproductive efficiency in dairy cattle

Abstract

In each of two dairy herds (A and B), rising yearling heifers (Trial 1) and adult cows (Trial 2) were assigned to three treatment groups. Untreated animals were compared to animals treated with either two or four intra-ruminal pellets containing 3 g of elemental selenium. The administration of pellets at the recommended dose (two pellets per animal) was effective in elevating whole blood glutathione peroxidase activity and selenium concentration to over 10 times those of control animals. In Trial 1, a 15% response in liveweight gain (p<0.001) occurred in yearling heifers in the herd with the lowest pre-treatment selenium status. In Trial 2, cows receiving two pellets produced a greater milk volume (p=0.06) and more milk solids (p=0.02) than untreated controls; an increase in volume of 5.4% and 8%, and in milk solids of 6.5% and 6.4%, were noted in herds A and B respectively. There was a trend towards decreasing somatic cell counts in milk from the treated cows when compared to controls, the four-pellet group in Herd A and the two-pellet group in Herd B being significantly different from their respective control group. No between-group differences were noted in calving-first service or calving-conception intervals, nor in the proportion of animals pregnant to first or all services. The administration of selenium at twice the recommended dose rate yielded no additional response above that noted after the administration of the recommended dose. The results of this study support the use of currently recommended Ministry of Agriculture and Fisheries selenium reference ranges in cattle for the prediction of a response to supplementation.

Effect of Different Levels of Selenium Supplementation on Growth Rate, Nutrient Utilization, Blood Metabolic Profile, and Immune Response in Lambs

“…Contrary to our observations, significantly higher feed conversion efficiency was observed in the Se-supplemented lambs [45]. Similarly, a higher feed conversion efficiency was observed on oral intra-ruminal Se pellet infusion in yearling heifers grazing on low (0.02-0.03 ppm) Se pasture [44] and in guinea pigs supplemented with 0.1, 0.2, and 0.3 ppm Se [32]. However, similar to our results, young cattle bulls fed different levels of Se through sodium selenite (0.08, 0.18, 0.58, and 1.08 ppm Se in total diet) for 4 months showed no difference in feed/gain ratio [46].…”

“…Similarly, there was no difference in the weight gain of growing cattle calves fed different levels (0.18, 0.29, 0.42, and 0.58 ppm) of Se in the diet for 7-8 months period [43]. However, there was a 15% higher live weight gain by oral intra ruminal Se pellet infusion in yearling heifers [44]. Similarly, Se supplementation at 0.5 and 1 mg/head for successive 3 days at 11 day's interval for 6 weeks improved the growth rate of the lambs [3].…”

Comparing the Effect of Oral Supplementation of Vitamin E, Injective Vitamin E and Selenium or Both during Late Pregnancy on Production and Reproductive Performance and Immune Function of Dairy Cows and Calves

“…Effects of Se and/or vitamin E on calf weight have been variable, with some studies reporting benefit effect [34, 35] and some reporting no effect [36, 37]. …”

Effects of increased iodine supply on the selenium status of kids

“…After the supplementation of animals with selenium, there appears to be an increase in the concentration of T 3 (Wichttel et al, 1994;Awadeh et al, 1998;Pavlata et al, 2004a). Other biological functions of selenium are carried out by a series of selenoproteins whose main role is participation in the removal of reactive forms of oxygen from the organism (Birringer et al, 2002).…”