Effect of the donor's age and type of extender (egg yolk versus clarified egg yolk) over the sperm quality of Majorera bucks preserved at 4°C: In vitro results and fertility trials.

This study assessed the effect of donor´s age and two different extenders in the sperm quality of chilled semen in Majorera bucks. In experiment 1, semen was individually processed from 5 young (10-12 months old) and 4 mature (3-5 years old) bucks and then was diluted in two different extenders: EY (Tris-glucose, 12% egg yolk) and CEY (Tris-glucose, 12% clarified egg yolk) and cooled at 4°C; semen quality (sperm motility, percentages of alive spermatozoa, acrosome status and abnormal spermatozoa) was evaluated at 24, 48, 72 and 96 hr after cooling. In experiment II, 72 Majorera goats were assigned to four experimental groups: for groups 24-EY (n = 18) and 24-CEY (n = 18), goats were inseminated with EY and CEY cooled semen for 24 hr, respectively, while for groups 72-EY (n = 18) and 72-CEY (n = 18), goats were inseminated with EY and CEY cooled semen for 72 hr, respectively. In vitro results confirmed that only ejaculate volume and sperm concentration were significantly different between young and mature bucks. In addition, semen quality was similar between both diluents, presenting values for the first 48 hr similar to that recorded in fresh samples. The fertility rate was around 70% after 24 hr (4°C) in both groups, but the kidding rate was significantly lower (44.4%, p < .05) in goats inseminated with EY diluent preserved for 72 hr. Our results showed that the semen samples may be stored at 4°C in media with egg yolk or clarified egg yolk, and, therefore, the use of clarified egg yolk may represent a valid alternative to chill semen samples. Finally, young bucks (older than 10-12 months) of Majorera breed could be successfully used in breeding programmes with similar efficacy to older males.

Microbial Prevalence and Antimicrobial Sensitivity in Equine Endometritis in Field Conditions.

Endometritis is one of the main causes of infertility in mares. In the present study, 363 mares with a history of repetitive infertility, and positive endometrial cytology and/or vaginal discharge were included. An endometrial swab for microbiological purposes plus sensitivity test was obtained from each mare. A positive culture was obtained in 89% of mares. The main isolated genera were Staphylococcus (25.1%), Streptococcus (18.2%), Escherichia (17.3%) and Pseudomonas (12.1%). With regard to species, the most isolated microorganism was Escherichia coli (17.3%), Staphylococcus spp. (15.6%) and Streptococcus spp. (13.5%). Sensitivity tests showed that the most efficient antimicrobial was amikacin (57.3% of cultures), followed by cefoxitin (48.6%) and gentamicin (48.3%). When sensitivity test was analyzed in terms of Gram+ and Gram- bacteria, Gram+ were highly resistant to cephaloridine (77.3% of cultures), apramycin (70.8%) and penicillin (62.3%), whereas Gram- were highly resistant to penicillin (85.8%), followed by cephaloridine (78.9%). In conclusion, the present study shows the most prevalent microorganisms isolated from equine endometritis, which were found to be resistant to ß-lactam antimicrobials. Likewise, these results highlight the significance of performing microbiological analyses as well as sensitivity tests prior to applying an antimicrobial therapy.

Anatomical Assessment of the Thorax in the Neonatal Foal Using Computed Tomography Angiography, Sectional Anatomy, and Gross Dissections.

The purpose of this study was to correlate the anatomic features of the normal thorax of neonatal foals identified by CTA, with anatomical sections and gross dissections. Contrast-enhanced transverse CTA images were obtained in three neonatal foals using a helical CT scanner. All sections were imaged with a bone, mediastinal, and lung windows setting. Moreover, cardiac volume-rendered reconstructed images were obtained. After CT imaging, the cadaver foals were sectioned and dissected to facilitate the interpretation of the intrathoracic cardiovascular structures to the corresponding CTA images. Anatomic details of the thorax of neonatal foals were identified according to the characteristics of CT density of the different organic tissues and compared with the corresponding anatomical sections and gross dissections. The information obtained provided a valid anatomic pattern of the thorax of foals, and useful information for CTA studies of this region.