High concentrations of ß-hydroxybutyrate alter the kinetics of bovine spermatozoa.

Postpartum cows, mainly with metabolic diseases, such as ketosis, usually experience an increased number of services per conception. During ketosis, high concentrations of ß-hydroxybutyrate (BHBA) in follicular, uterine and oviductal fluid have been considered to cause subfertility in cows. However, the effect of sperm exposure to an environment with high BHBA concentration is not known. This study investigated the influence of high levels of BHBA on kinetics, oxidative status and morphology of bovine spermatozoa. To assess the effect of BHBA after sperm selection, bovine spermatozoa were incubated (180 min) with different BHBA concentrations: 0 (Control), 0.8, 2.4 or 5 mM. Sperm kinetics was evaluated after 30, 60, 120 and 180 min, and oxidative status and morphology were analysed at 180 min. Oxidative status was evaluated through the production of reactive oxidative species (ROS), total antioxidant capacity and lipid peroxidation. High concentrations of BHBA decreased the curvilinear velocity, straight line velocity, mean path velocity, linearity, straightness and hyperactivity of spermatozoa. However, there was no effect of BHBA on oxidative and antioxidant capacity as well as on sperm morphology. In conclusion, exposure of bovine spermatozoa to high levels of BHBA impairs sperm kinetics without altering oxidative and antioxidant mechanisms.

Decreasing the dose of equine chorionic gonadotropin does not affect ovarian or pregnancy responses of purebred taurine and crossbred beef heifers.

In this study there was evaluation of effects of different doses of equine chorionic gonadotropin (eCG: 200, 300, or 400 IU) administrated at progesterone (P4) plus estradiol-based timed AI (TAI). A total of 1080 heifers were included in the study. There was insertion of the intravaginal P4-device plus administration of 2 mg of estradiol benzoate IM. On D7, 12.5 mg of dinoprost tromethamine IM was administered and on D9, the P4 insert was removed and 0.5 mg of estradiol cypionate IM was administered. Heifers were categorized according to Reproductive Tract Status (RTS; 1-5) and were assigned to one of three treatments: 200 IU (n = 387), 300 IU (n = 357), or 400 IU (n = 336) of eCG. Estrous occurrence was evaluated at TAI 48 h later (D11). A subset of heifers (n = 213) had the largest follicle (LF) evaluated on D9 and on D11, and the formation of a new CL evaluated on D18.There was no effect of eCG treatment on LF on D11 (P = 0.79), occurrence of estrus (P = 0.92), and pregnancy at 30 days after AI (P/AI; 52.2%, 49.8%, and 51.5% for 200 IU, 300 IU, and 400 IU, respectively; P = 0.46). Regardless of the treatment, there was a greater P/AI when heifers had a functional CL, at initiation of the estrous synchronization treatment regimen. It, therefore, is efficacious to reduce the dose of eCG to 300 or 200 IU in purebred taurine and crossbred beef heifers without negative effects on ovarian, estrous or pregnancy responses.

Tribulus terrestris Protects against Male Reproductive Damage Induced by Cyclophosphamide in Mice.

Tribulus terrestris (TT) has been considered as a potential stimulator of testosterone production, which has been related with steroidal saponins prevailing in this plant. Cyclophosphamide (CP) is the most commonly used anticancer and immunosuppressant drug, which causes several toxic effects, especially on the reproductive system. Patients who need to use CP therapy exhibit reduced fertility or infertility, which impacts both physically and emotionally on the decision to use this drug, especially among young men. We hypothesized that the treatment with TT dry extract would protect the male reproductive system against CP toxicity. Mice received dry extract of TT (11 mg/kg) or vehicle by gavage for 14 days. Saline or CP was injected intraperitoneally at a single dose (100 mg/kg) on the 14th day. Animals were euthanized 24 h after CP administration, and testes and epididymis were removed for biochemical and histopathological analysis and sperm evaluation. The dry extract of TT was evaluated by HPLC analysis and demonstrated the presence of protodioscin (1.48%, w/w). CP exposure increased lipid peroxidation, reactive species, and protein carbonylation and altered antioxidant enzymes (SOD, CAT, GPx, GST, and GR). Moreover, acute exposure to CP caused a reduction on 17 ß-HSD activity, which may be related to the reduction in serum testosterone levels, histopathological changes observed in the testes, and the quality of the semen. The present study highlighted the role of TT dry extract to ameliorate the alterations induced by CP administration in mice testes, probably due to the presence of protodioscin.

Superstimulation with eCG prior to ovum pick-up improves follicular development and fertilization rate of cattle oocytes.

This study aimed to evaluate the effect of equine chorionic gonadotrophin (eCG) stimulation prior to ovum pick-up (OPU) on follicular development, number and quality of recovered oocytes, fertilization rate, and early embryo development in vitro. There were four OPU sessions (cross over) conducted on 16 Braford cows to evaluate the effect of various eCG doses. The timing of the wave of ovarian follicular development was synchronized, and three days after, the respective eCG dose was administrated (0, 200, 400, or 800 IU). The OPU was performed on Day 6, and viable oocytes were used for IVM and IVF according to the respective treatment. After IVF treatment, the fertilization and cleavage rates, time of cleavage, and the cell number at 48 h were evaluated. There was no difference in the number of follicles, oocyte quantity, and morphological quality of oocytes among treatments (P > 0.05). The oocyte recovery rate was similar among the eCG-treated groups, but was less than in the control group (P < 0.01). The eCG800 group, however, had a greater recovery rate of follicles >6 mm in diameter (P < 0.01). In addition, the eCG800 group had a greater rate of normal fertilization (P < 0.01) and lesser rate of polyspermy (P < 0.02). The cleavage rate of the eCG800 group was greater than the other treatment groups but similar to that of the control. In conclusion, the use of eCG800 increased the proportion of follicles > 6 mm, with improved rate of normal fertilization and reduced occurrence of polyspermy, without affecting early embryonic development in vitro.

Blueberry (Vaccinium ashei Reade) extract ameliorates ovarian damage induced by subchronic cadmium exposure in mice: Potential δ-ALA-D involvement.

Females are born with a finite number of oocyte-containing follicles and ovary damage results in reduced fertility. Cadmium accumulates in the reproductive system, damaging it, and the cigarette smoke is a potential exposure route. Natural therapies are relevant to health benefits and disease prevention. This study verified the effect of cadmium exposure on the ovaries of mice and the blueberry extract as a potential therapy. Blueberry therapy was effective in restoring reactive species levels and δ-aminolevulinate dehydratase activity, and partially improved the viability of cadmium-disrupted follicles. This therapy was not able to restore the 17 ß-hydroxysteroid dehydrogenase activity. Extract HPLC evaluation indicated the presence of quercetin, quercitrin, isoquercetin, and ascorbic acid. Ascorbic acid was the major substance and its concentration was 620.24 µg/mL. Thus, cadmium accumulates in the ovaries of mice after subchronic exposure, inducing cellular damage, and the blueberry extract possesses antioxidant properties that could protect, at least in part, the ovarian tissue from cadmium toxicity. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 188-196, 2017.