Effect of different concentrations of Trolox® in association with docosahexaenoic acid on equine semen freezing

The aim of this study was to evaluate the association of different concentrations of Trolox^® and the addition of a fixed concentration of DHA in the freezing of semen of Mangalarga Marchador stallions. To that end, 16 ejaculates were frozen in the following extenders: E1) BotuCrio^® (BC; Control); E2) BC + 50 ngml^-1 DHA + 30 µM Trolox^® (BCDHA30T); E3) BC + 50 ngml^-1 DHA + 40 µM Trolox^® (BCDHA40T); E4) BC + 50 ngml^-1 DHA + 50 µM Trolox^® (BCDHA50T). All the tested extenders were similar in preserving different kinematic parameters, cell functional integrity, compacted DNA, and high and intermediate mitochondrial activity (P>0.05). However, sperm cryopreserved in BCDHA40T showed higher velocities than sperm frozen in the control extender (P<0.05). The 30 µM concentration of Trolox^® was worse for sperm motility and the 50 µM concentration of Trolox^® did not adequately preserve the structural integrity of the membranes in an extender containing DHA when compared to the BotuCrio^® (P<0.05) extender. The use of Trolox^® in freezing extenders containing DHA did not maximize the effect of BotuCrio^®, except for in the case of sperm velocity parameters when at a concentration of 40 µM.

Chemical Restraining and Electroejaculation Protocols for Semen Collection in White-Lipped Peccary (Tayassu pecari)

Background: In order to reverse the White-lipped peccary decline, besides protecting its habitat and controlling hunting, it is necessary a captive breeding program. There are reports, however, on the low fertility of white-lipped peccary, making it difficult its reproduction in captivity, making artificial insemination one of the main tools to prevent the loss of genetic diversity of species kept in captivity. Information on safe methods of anesthesia and the collection of semen should be investigated. Therefore, we aimed to compare the effects of the anesthetic protocols acepromazine/ketamine and xylazine/ketamine, as well as electroejaculation protocols, for semen collection in white-lipped peccary (Tayassu pecari).Materials, Methods & Results: Twelve adult male white-lipped peccaries were submitted both to the xylazine/ketamine and acepromazine/ketamine anesthetic protocols. The anesthetic induction time and duration, the degree of muscle relaxation, the time for anesthetic recovery and the quality of the animals’ recovery were evaluated. Additionally, the quality of the sedation was evaluated based on the animal’s behavior. We also evaluated the effect of drugs on erectile functions as well as the efficiency of three electroejaculation protocols with increasing or fixed voltages (2 to 4 V; 5 to 12 V; 12 V). The acepromazine/ketamine combination promotes shorter induction time, duration and recovery from anesthesia than the xylazine/ketamine association. There were no differences, however, between the tested anesthetic protocols in relation to heart rate, respiratory rate and temperature. Ejaculate was obtained from only 2 animals when using the xylazine/ketamine protocol and adoption of stimuli between 5 and 12 V, with 10 stimuli at each voltage. In turn, ejaculate was obtained from four animals submitted to the acepromazine/ketamine protocol, three of them with the adoption of stimuli between 5 and 12 V and one with the adoption of fixed 12 V stimuli, with 45 stimuli at this single voltage.Discussion: The animals presented less deep anesthesia and, consequently, worse indicators of well-being during and after the collection procedures when submitted to the xylazine/ketamine protocol compared to the acepromazine/ketamine protocol. When submitted to the acepromazine/ketamine protocol, the animals allowed the observer to approach and handle them, facilitating handling and collection of semen, in addition to promoting better indicators of animal welfare. Also, with this aforementioned protocol, the animals showed better anesthetic return. For both anesthetic protocols, the protocol of increasing stimuli from 5 to 12 V, with 10 stimuli at each voltage, resulted in penile erection and in obtaining ejaculate in a greater number of animals in relation to the other electroejaculation protocols. In turn, the use of the growing protocol 2 V to 4 V did not even cause an erection in any of the 12 animals. From the ejaculates collected from the white-lipped peccary, volumes (0.2 to 1.0 mL) and average sperm concentration (379.1 x 106 sperm/mL) were comparatively higher than those from Pecari tajacu. The white-lipped peccary (Tayassu pecari) is considered an aggressive animal, and this characteristic can explain the relatively low success in obtaining ejaculates, as aggressiveness is directly related to stress, which is an antagonist of ejaculation. Thus, we proposed to test chemical restraint with the aid of a blowgun in future studies.

Return of postpartum ovarian activity in dairy goats supplemented with different levels of energy

This study aimed to evaluate the return of post partum ovarian activity in dairy goats supplemented with different levels of energy during the dry period in the semi-arid region of Pernambuco. Twenty-four animals were allocated into four treatments of six animals each: Control, consisting of goats that had access to pasture and only received 4 kg of fresh palm, and three groups with isoproteic supplementation (20% Crude Protein), ranging in TDN content of 65%, 75% and 85%. The daily milk yield showed a linear growth behavior (P <0.05) since day 35th postpartum, when the animals recovered the weight gain and body condition score after 14 and 21 days postpartum, respectively, with slight weight gain in 75% and 85% treatments. Among the reproductive parameters, uterine involution and return to estrus activity showed a decrease in the number of days associated with the higher energy levels (P <0.05). The emergence of the 1st follicles > 2 mm occurred around 33 days postpartum and the maximum diameter of the pre-ovulatory follicle was 5,41mm. These results were not influenced by treatments (P> 0.05). We concluded that the supplementation with different levels of energy promoted a positive effect, as increased productive parameters and reduced the number of days for the reestablishment of the reproductive parameters postpartum; for instance, uterine involution, return to estrus and consequently return of ovarian activity postpartum.