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During the transition period, high-yielding dairy cows suffer from negative energy balance, intense lipomobilization and impaired lipid metabolism; this metabolic condition can lead to overburdened triglycerides accumulation in the liver, known as liver lipidosis, which has been associated to impaired fertility in dairy cows. The mechanisms of this impairment can be in principle correlated with the presence and the extent of ectopic fat depots. However, current methods for evaluating fat accumulation in liver and in the reproductive tract suffer from low resolution, sensitivity, and specificity. Confocal microscopes are equipped with Gallium arsenide phosphide detectors, thus enabling the acquisition of intense signals from tissue biopsies. This method could differentiate whether fat deposition occurred without requiring sample sectioning. Here, we examined with this technique liver, uterine and ovarian samples of heifers and regularly slaughtered repeat breeder and overconditioned dairy cows, to quantify lipid droplets and depots at a submicrometer scale with high specificity. With the aid of this technique, we found lipid depots in uterine and ovarian specimens. Moreover, we found that the size and number of depots increased with the degree of liver lipidosis. Further studies are needed to elucidate the relationship between the severity and extent of these deposits and the fertility of lactating dairy cows. Since tissues other than liver display different characteristic lipid droplet distributions, this technique can be potentially employed to shed new light on the pathogenesis of lipidosis and to assess new risk factors for infertility., (Copyright © 2018 Elsevier Inc. All rights reserved.)

High-yielding dairy cows are metabolically challenged during transition, when intense mobilization and hepatic oxidation of lipids is achieved, thus leading to fatty infiltration, ketosis and generalized inflammation. The condition is associated to periparturient diseases and poor fertility. The aim of this study was to assess whether serum lipoprotein concentrations in the dry period could influence the occurrence of postpartum diseases and reproductive performance in dairy cows. The study was carried out on 30 multiparous Holstein Friesian cows. Blood samples were collected at dry-off (-60 days), 30 days after dry-off and within 12 h after parturition for biochemical and serum lipoprotein assays. From 10 to 60 days after parturition milk was collected twice weekly after feeding, for milk whey progesterone assay. The Optimal Cutpoint package identified a threshold of 89% for serum High Density Lipoprotein (HDL) concentration at the beginning of the dry period with 95% of confidence interval. Cows with serum HDL greater than 89% (High group, n = 10) showed better reproductive performance when compared to those with low values (Low group, n = 18). The odds ratio for reproductive disorders in High group was 0.6875, however, differences were not significant probably due to both the reduced number of animals per group and overall low incidence of postpartum reproductive disease. First postpartum luteal activity occurred around day 23, while the second one between days 40 and 48. The average calving to first AI interval was 64.00 ± 3.95 days and 94.50 ± 12.32 days in High and Low group, respectively (P < 0.05). The calving-conception interval was 129.86 ± 24.42 days and 199.18 ± 24.73 days in High and Low groups, respectively (P < 0.05). Low group displayed an increase in liver markers, that is total bilirubin, with 0.46 ± 0.09 mg/dL and 0.23 ± 0.08 mg/dL, in Low and High group respectively (P < 0.05), and NEFA/cholesterol ratio, with 0.30 ± 0.06 and 0.14 ± 0.03, in Low and High groups, respectively (P < 0.05), at parturition. Concentrations of HDL >89% at dry-off could be suggestive of improved liver adaptation to the transition, and probably of enhanced fertility in High group., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Traditional superovulation protocols that include multiple gonadotropin treatments are time-consuming and labor intensive. These protocols require multiple handling and restraining of embryo donors. This will likely increase the risks of injuries in both animals and humans and induce stress that may lead to a reduced superovulatory response. These are more evident when working with cattle that are rarely handled or raised on extensive grazing. The objectives of this experiment were to compare the efficacy of a split-injection protocol of porcine pituitary-derived porcine FSH (pFSH) preparation (slow release [SR] group) to the traditional 4-day treatment with pFSH administered twice daily (C group) and to determine the concentrations of cortisol in the hair as a marker of activation of the hypothalamic-pituitary-adrenal (HPA) axis during the two superovulatory treatments. Thirty-two heifers were stimulated twice in a 2 × 2 crossover design and compared for ovarian response and numbers and characteristics of recovered ova-embryo among treatments. No differences between SR and C groups were found in terms of percentage of responsive animals (100% vs. 93.8%) and ovulation rate (83.7 ± 1.1 vs. 79.5 ± 1.0%). A positive correlation was found between the number of follicles responsive to pFSH (2-8 mm) at the beginning of treatments and the superovulatory response, and no differences were found in these follicular populations between the two treatment groups. The numbers of CLs, ova-embryos, fertilized ova, transferable and freezable embryos recovered per cow were found to be significantly higher in SR compared with C group (14.0 ± 1.6 vs. 10.6 ± 1.0, 12.1 ± 1.6 vs. 7.6 ± 1.0, 11.1 ± 1.1 vs. 7.3 ± 1.0, 9.6 ± 1.4 vs. 6.6 ± 1.0, and 9.4 ± 1.4 vs. 6.0 ± 1.0 for SR and C group, respectively). The SR group produced also a significantly greater number of excellent- and/or good-quality embryos compared with the C group. The concentrations of cortisol in the hair at Days 14 and 21 were significantly greater in the C compared with the SR group (P < 0.05). In conclusion, these results indicate that the dilution of gonadotropin in a 0.5% hyaluronan solution, reducing the administration frequency, improves the quantitative and qualitative superovulatory response of Marchigiana heifers [corrected]. Further studies using other breeds of cattle are needed to verify the results herein obtained and to confirm the lower activation of the hypothalamic-pituitary-adrenal axis caused in the donor by the split-injection protocol., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Although semen quality is one of the major traits that influence breeding soundness examination outcomes in bulls, field conditions occasionally do not allow for the collection of semen samples by means of an artificial vagina. The aims of the present study were to report the results of a large number of semen collections that were performed via the transrectal massage (TRM) of the accessory sexual glands of Italian yearling beef bulls and compare this semen collection method to the artificial vagina (AV) method in term of breeding soundness examination outcomes; furthermore, we determined whether the breed affected the semen characteristics. In the TRM group (n = 475), the semen samples were collected via TRM of the accessory sexual glands, and in the AV group (n = 502), the AV method was used. In the TRM group, semen samples were obtained from 81.3% of the bulls and penile protrusion was observed in 87.6% of the animals during semen collection. The sperm concentrations (920.5 ± 439.0 vs. 281.0 ± 259.8 × 10(6)/mL) and the percentages of total abnormal spermatozoa (22.8 ± 15.0 vs. 18.8 ± 12.9) were significantly higher in the AV group than those in the TRM group. The percentage of bulls that did not meet the minimum requirement for normal cells (≥70%) was 6.2% higher in the AV group than that in the TRM group (P < 0.05). Moreover, the samples collected from Chianina bulls by TRM exhibited a lower percentage of motile sperm and a higher percentage of abnormal spermatozoa when compared with the other two breeds. The major drawbacks of the TRM technique were the inability to conduct complete evaluation of the libido and mating ability of the yearling bulls, a significant reduction of the number of spermatozoa collected, and an increase in the variability of the semen characteristics due to breed. In conclusion, despite the drawbacks, TRM guarantees that semen evaluation can be conducted in cases in which the semen samples cannot be collected with the AV method., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Granulosa-theca cell tumors (GTCTs) are able to secrete variable amounts of sex steroids and immunoreactive inhibin (ir-INH). Although the pituitary appears to be affected by the presence of a GTCT, pituitary responsiveness to exogenous GnRH has not been examined. The aims of the present study were to: (i) assess the plasma hormone concentrations of ir-INH, gonadotropins and sex steroids in eight mares with GTCT and (ii) assess the responsiveness of pituitary gonadotroph cells to exogenous GnRH stimulus both before and after tumor removal. In seven mares, the contralateral ovary was firm, small and inactive. Histopathological observations of the tumors confirmed the presumptive diagnosis of a GTCT. Four mares, judged to be in vernal transition period (n=2) and in the breeding season (n=2), were used as controls. A single intravenous injection of 40 microg of GnRH agonist was given to each mare and blood samples were collected every 15 min from 2 h before to 4 h after injection. In four GTCT mares, this procedure was repeated 20 (n=2) and 90 (n=2) days after tumors removal. All plasma samples were analyzed for concentrations of ir-INH, LH, FSH, estradiol-17beta (E2), testosterone (T) by RIA and progesterone (P) by EIA. Results showed that E2 levels were significantly higher (P<0.001) in control animals compared to E2 levels in GTCT mares before and after surgery. P and T concentrations were not statistically different between the groups. Baseline levels of ir-INH were greater (P<0.05) in GTCT mares before surgery than in control mares, and decreased to undetectable levels after neoplasia ablation. Baseline FSH did not differ between control and GTCT animals either before or after the ovaries were removed. LH baseline values appeared to be higher for affected mares, but the difference was not statistically significant. Maximum release (MR) and area under the gonadotrophin release curve (AUC) after the GnRH challenge for both the gonadotrophins were similar between the groups.

The effect of orally administered l-carnitine on the quality of semen obtained from stallions with different semen qualities was investigated. Four stallions with proven fertility (high motility group, HM) and with normal seminal characteristics (>50% progressive motility and > 80 x 10(6) spermatozoa/ml), and four questionable breeders (low motility group, LM) with <50% of sperm progressive motility and < 80 x 10(6) spermatozoa/ml, received p.o. 20 g of l-carnitine for 60 days. Blood and semen samples were collected before treatment (T0) and after 30 (T1) and 60 days (T2). Semen evaluation were performed on five consecutive daily ejaculates (n = 120 ejaculates) and conventional semen analysis was carried out on each ejaculate, both at collection and after refrigeration for 24, 48, and 72 h. Furthermore l-carnitine, acetylcarnitine, pyruvate, and lactate concentrations, and carnitine acetyltransferase activity (CAT) were determined both in raw semen and seminal plasma. There were an increase in progressive motile spermatozoa only in the LM group (26.8 +/- 12.9, 39.1 +/- 15.5, and 48.8 +/- 8.6 for T0, T1, and T2, respectively). Free seminal plasma carnitine concentration was higher in the LM group compared to the HM one. Both pyruvate and lactate were higher in the LM group. Raw semen and seminal plasma carnitine and acetylcarnitine levels correlate positively with both sperm concentration and progressive motility; moreover, acetylcarnitine content was positively correlated with total motile morphologically normal spermatozoa. In conclusion, oral administration of l-carnitine to stallions with questionable seminal characteristics may improve spermatozoa kinetics and morphological characteristics; whereas, it seem to be ineffective in normospermic animals.