Suplementação energética, vitamínica e mineral Canter OF®. em doadoras de embriões bovinos

Abstract

A female bovine used as a donor in embryo transfer programs (ET) should produce structures with quality and quantity. The improvement of the efficiency of livestock production is a complex biological system involving interactions of hormonal, genetic, metabolic and nutritional factors. Nutrition and reproduction are closely linked in any production system. Canter OF is a nutritional supplement with vitamins, minerals and amino acids, which could improve the performace of female cattle in superovulation programs. The purpose of this paper was to verify the effects of the of Canter OF adiminitration on the superovulatory response and embryo production in (ET) zebu cows. Forty-two superovulation protocols were carried out with , on 21 Guzerá breed female bovine doners, aged 20-60 months, weighing more than 350 kg, and having normal estrous cycles (21 ± 3 days). The animals were kept in semiconfinement and received the same diet during the trial period, consisting of grass and mineral supplementation ad libitum to maintain the body condition score of between 3 and 4 (scale of 1 to 5). All animals passed thorough both the group (Canter OF ) and the control group atleast once, in Cross-over design. The product was administrated daily (20 ml) to each donor individually during the trial period. The following variables: influence of the treatments on the ovarian response to the ovarian response to the superovulatory protocol (numberand average diameter of follicles on insemination day); number of corpora lutea present on flushing day; embryo recovery rate; total embryos; number of and degenerate embryos and nofertilized eggs, and recipient gestation rate. The results showed that no difference (P> 0.05) was found between the number of corpora lutea (10.20 ± 2.04 and 9.79 ± 1.73 to a), total embryos ( 7.64 ± 2.06 to 6.64 ± 1.71) and viable embryos (4.64 ± 1.24 and 4.68 ± 1.03 to a) and between the control group and the Canter OF group, respectively. When evaluation concerned only the cows with low superovulatory response and poor embryo production, the results with Canter OF treatment were different were different. In this group, Canter OF treatments were different. In this group, Canter OF treatment increased the superovulatory response, the number of embryos per flushing, and the number of viable embryos (P <0.05). It the animals with a history of good superovulatory response no statistically significant alteration was found. In conclusion, the product used in the present protocol was effective to increase the superovulatory response and embryo production only in a donor with a low embryo production.