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ABSTRACT: The appearance of a decisive component of the sexual response to chemosexual signals in the male donkey was investigated through a comparison of the variations in the time-span of the behavioral classes and units for the natural versus induced breeding seasons. The results demonstrate that there are significant variations in the length of the appetitive sexual behavior (ASB) and consummatory sexual behavior (CSB) under these two reproductive conditions. These differences are analyzed for the ASB, which is adaptable, compared with the stereotyped CSB. For the ASB, male isolation is the most represented behavior of both the natural and induced breeding seasons. This is the key that allows the passage from courtship, which consist of appetitive behaviors, to copula, the consummatory behavior. This isolation appears to provide the time required to activate the hypothalamic-pituitary-gonadal axis through the chemosexual pathway of pheromone stimuli. This isolation is lengthened with induced breeding, supporting the hypothesis of the activation of the neuroendocrine system, which is not 'primed' outside the natural breeding season, and which is necessary to release the stereotyped CSB.
Physiology & Behavior 05/2013; · 2.87 Impact Factor
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ABSTRACT: Spermatozoa acquire their motility and fertilizing ability during their passage through the epididymal canal. In the epididymal caput and corpus spermatozoa undergo several biochemical and metabolic changes while the cauda of the epididymis should be considered as the primarily site for storage of the spermatozoa. In the horse spermatozoa from cauda epididymis were collected and frozen, and the fertility of semen assessed. However, no studies have detailed semen characteristics of spermatozoa collected from the cauda epididymis in the jackass. In this study sperm characteristics of spermatozoa in the cauda epididymis of the donkey was reported and a comparison with ejaculated spermatozoal characteristics was performed. Samples from 10 Martina Franca jackasses were collected and analyzed for viability (Propidium iodide/Sybr-14® fluorescent stain), mitochondrial activity (Mitotraker® fluorescent stain), objective motility characteristics (by Computer Assisted Sperm Analyzer - CASA) and morphology. A higher viability and mitochondrial activity in the cauda epididymis samples were reported in this paper. Samples reported in this paper were identified and the percentage of total and progressive spermatozoa was comparable, but trajectories were more rapid (higher VCL) with less progressiveness (higher ALH and lower STR and LIN) in the cauda epididymis. Sperm morphology showed a pronounced variability between jackasses, with comparable values for all morphological subclasses. In this study the loss of the distal cytoplasmic droplets happen close to or after ejaculation because the percentage fell to nearly 0% after ejaculation. As suggested for bulls, the presence of a similar percentage in sperm with proximal cytoplasmic droplet in epididymal and ejaculated semen is likely to indicate a failure in the maturation process.
Animal reproduction science 10/2011; 128(1-4):117-22. · 1.56 Impact Factor
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ABSTRACT: In this study, the effect of dietary supplementation of organic selenium, vitamin E, and zinc on raw semen characteristics was evaluated. Ten stallions with normal fertility were divided into two groups: a control group (CG), in which standard diet was provided, and a treated group (TG), in which the standard diet was supplemented with 1500 mg of α-tocopherol acetate, 360 mg of zinc, and 2.5 mg of organic selenium on a daily basis. Semen parameters on fresh semen were evaluated three times in all stallions before antioxidant supplementation (T0) and 30 (T1), 60 (T2), and 90 (T3) d after supplementation. Dietary supplementation with experimental antioxidants resulted in a significant increase in average path velocity (121.9 ± 3.1 μm/sec in TG vs 118.9 ± 4.3 μm/sec in CG), straightness (86.2 ± 2.4 % vs 82.6 ± 3.9 % in TG and CG respectively), viability (75.6 ± 10.2 % in TG vs 72.3 ± 6.9 % in CG) and total seminal plasma antioxidants levels (2.7 ± 0.5 mmol/l vs 1.9 ± 0.4 mmol/l in TG and CG respectively) while progressive motility 69.7 ± 11 % vs 62.2 ± 9.3 % in TG and CG stallions respectively) and abnormal sperm morphology (8.2±1.5 % in TG vs 14.4±4 % in CG) significantly improved in treated stallions after 60 d of supplementation. In contrast with previously reported in other species, a negative effect of antioxidant supplementation on semen concentration was recorded in the TG. A positive correlation between progressive motility and total antioxidants in seminal plasma in both treated and control stallions suggested that motility is affected by oxidative-antioxidative status, and that dietary antioxidant supplementation could increase the ability of spermatozoa to contrast reactive oxygen species or the ability of seminal plasma to reduce the oxidative stress. The improvement of semen parameters after antioxidant supplementation was not linear, and after 30 d (or 60 d for some parameters), a further increase was not noted. This evidence suggested that in our standard conditions, dietary intake of these antioxidants could be slightly under the dietary requirement and further evaluation of the actual nutrition requirements of organic selenium, zinc, and vitamin E in the stallion are needed.
Theriogenology 02/2011; 75(7):1319-26. · 1.96 Impact Factor
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ABSTRACT: Artificial insemination with cooled semen is routine in equids because of its good fertility rates and relatively low costs. In several donkey breeds, especially in restricted populations, the use of cooled semen could be seen as the best way of improving reproductive performance and avoiding excessive inbreeding. Furthermore, most jennies have ovulatory estrous throughout the year, and thus, cooled semen could also be used during short day length season. The aims of this study were to evaluate the effects of different extenders on sperm quality during cooling in the Martina Franca breed, and to verify the preservation of cooled semen collected during long day length (May-June) and short day length (November-December) seasons. Three ejaculates were collected at 10-day intervals from each of six jackasses during both May-June and again in November-December time periods. Each ejaculate was cooled in INRA96 or E-Z Mixin at a low cooling rate and evaluated daily over a 120-h preservation time. The results showed a significant extender influence on preservation time in both periods. Semen diluted with INRA96 maintained a progressive motility of 36% and a straightness of 89% at 120h, whereas semen extended with E-Z Mixin had a mean progressive motility of 32% and a straightness of 81% at 48h during the May-June period. Despite having the same initial characteristics, semen collected during the short day length season had a higher rate of decline in semen quality during storage at 5 degrees C with E-Z Mixin.
Animal reproduction science 03/2010; 120(1-4):136-41. · 1.56 Impact Factor
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ABSTRACT: Equine cutaneous habronemosis, also known as "summer sores", is a parasitic infection caused by larvae of Habronema microstoma and Habronema muscae (Nematoda, Spirurida) released by dung-inhabiting fly vectors on abraded skin, skin wounds or muco-cutaneous transition sites. Larvae induce a local inflammatory reaction characterised by itching, granulomatous, ulcerated and, often non-healing, lesions. The diagnosis of summer sores may be unreliable mainly because of the limits of clinical and microscopic examination. The applicability of a semi-nested PCR assay developed for the diagnosis of gastric habronemosis has been herein demonstrated for the detection of the cutaneous infection. The potential applicability of this diagnostic tool may have for clinical and epidemiological studies of cutaneous habronemosis in equids is discussed.
Veterinary Parasitology 12/2007; 150(1-2):116-21. · 2.58 Impact Factor
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ABSTRACT: To determine survival rate, complications, and short-term fertility rate after fetotomy in mares.
Retrospective study.
72 mares with severe dystocia.
Records from 1991 to 2005 were searched for mares with dystocia in which a fetotomy was performed. Data relating to presentation and position of foals; survival rate, complications, and short-term fertility rate in mares; and 45-day pregnancy rate in mares bred 2 to 3 months after fetotomy were recorded.
Anterior fetal presentation was detected for 54 of 72 (75%) mares, posterior presentation was detected for 13 (18.1%), and transverse presentation was detected for 5 (6.9%). One fetus in anterior presentation was hydrocephalic. Survival rate after fetotomy was 95.8%. Complications included retained fetal membranes (5.5%), laminitis (6.9%), vaginal and cervical lacerations (2.8%), and delayed uterine involution (2.8%). Mares bred 2 to 3 months after fetotomy had good short-term fertility, with a mean pregnancy rate of 79.4% at 45 days after breeding.
The survival rate was high, compared with rates reported after cesarean section, and short-term fertility rate was similar to those reported for mares that had a controlled vaginal delivery or cesarean section. Fetotomy performed by a skilled veterinarian on a nonviable fetus should be considered as a means of quick and safe correction of dystocia that does not necessarily impair short-term fertility in affected mares.
Journal of the American Veterinary Medical Association 06/2007; 230(10):1502-5. · 1.79 Impact Factor
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ABSTRACT: The chamois of Abruzzi (Rupicapra pyrenaica ornata) has been classified as endangered by the World Union for Conservation. The objective of this study was to analyze seasonal differences in the characteristics of various male reproductive organs and in semen quality. The study was conduced during 2004 in the reserve of Lama dei Peligni (Italy) on three chamois males aged between 2 and 5 years. Males were captured during March-May months and October-December months. Various testicular and scrotal measurements were taken and semen was collected using an electroejaculator. Sperm motility pattern was evaluated using computer assisted sperm analyzer, membrane integrity using differential staining and morphology with phase contrast microscopy. Testicular size, sperm motility membrane integrity and the percent of morphological normal spermatozoa were greater during October-December. The authors concluded that sperm characteristics are strongly influenced by season and that semen collected in this period (breeding season) has suitable quality for manipulation and long-term preservation.
Animal Reproduction Science 02/2007; 97(1-2):186-90. · 1.75 Impact Factor
