Bilateral Ovotestes in a 78, XX SRY-Negative Beagle Dog.

This report describes a disorder of the sexual development in a beagle dog resulting in an intersex condition. A 6 mo old beagle was presented for evaluation of a protruding structure from the vulva consistent with an enlarged clitoris. Ultrasonographic examination revealed the presence of both gonadal and uterine structures. Retrograde cystourethrovaginogram showed the presence of an os clitoris and severe vaginal stenosis. Histological studies revealed the presence of bilateral ovotestes and uterus. The gonad had interstitial cells within seminiferous-like tubules lined only with Sertoli cells and abundant interstitial cells among primordial, primary, and secondary follicles. Hormone assays completed before and after gonadohysterectomy showed an elevation in the levels of progesterone and dihydrotestosterone that returned to baseline 3 mo after surgery. Testosterone levels that were within the male reference ranges before surgery decreased to basal levels postsurgically. 17-ß-Estradiol levels showed little variation and values were always within the reference ranges for a male. Cytogenetic analysis showed a normal female karyotype (2n = 78, XX) and polymerase chain reaction analysis revealed the absence of the sex-determining region Y gene. In summary, the dog presented bilateral ovotestes and a 2n = 78, XX chromosomal complement lacking the sex determining region Y gene, consistent with a diagnosis of true hermaphroditism.

Alterations in the glutathione metabolism could be implicated in the ischemia-induced small intestinal cell damage in horses.

BACKGROUND: Colic could be accompanied by changes in the morphology and physiology of organs and tissues, such as the intestine. This process might be, at least in part, due to the accumulation of oxidative damage induced by reactive oxygen (ROS) and reactive nitrogen species (RNS), secondary to intestinal ischemia. Glutathione (GSH), being the major intracellular thiol, provides protection against oxidative injury. The aim of this study was to investigate whether ischemia-induced intestinal injury could be related with alterations in GSH metabolism. RESULTS: Ischemia induced a significant increase in lipid hydroperoxides, nitric oxide and carbon monoxide, and a reduction in reduced glutathione, and adenosine triphosphate (ATP) content, as well as in methionine-adenosyl-transferase and methyl-transferase activities. CONCLUSION: Our results suggest that ischemia induces harmful effects on equine small intestine, probably due to an increase in oxidative damage and proinflammatory molecules. This effect could be mediated, at least in part, by impairment in glutathione metabolism.

The effect of methyl sulphonyl methane supplementation on biomarkers of oxidative stress in sport horses following jumping exercise.

BACKGROUND: Exercise induces changes in several organs and tissues, and this process might be due to oxidative damage caused by free radicals and inflammatory mediators. Methyl Sulphonyl Methane, better known as MSM, is a naturally occurring sulphur compound with well-known antioxidant properties. On the other hand, Vitamin C is important in limiting free radical damage in the aqueous phase of the cell, and cellular vitamin C status may be linked to the mechanisms involved in quenching cellular reactive oxygen species. The aim of this study was to determine if supplementation with MSM and vitamin C could alleviate exercise-induced oxidative stress in horses undergoing jumping competition. METHODS: Twenty four jumping horses involved in competition were used. Horses were given the following three treatment diets: control (without supplementation), MSM 8 mg/kg, and combined supplements (MSM 8 mg/kg + Vit-C 5 mg/kg). EDTA blood samples were collected before exercise, upon arrived to the schooling area (control), and each week after last show. Nitric oxide, carbon monoxide, lipid hydroperoxides and the antioxidant enzymes, glutathione peroxidase, glutathione transferase and glutathione reductase, plasma levels were determined. RESULTS: Competition induced a significant increase in lipid peroxidation, nitric oxide and carbon monoxide. By contrary, reduced glutathione as well as antioxidant enzyme activities, were decreased. MSM administration significantly ameliorated all these exercise-related changes, and this effect was potentiated by Vit C reaching values in some of the parameters similar to those found before competition. CONCLUSION: These results suggest that jumping exercise could induce harmful effects on horses, probably due to an increase in oxidative damage and proinflammatory molecules. In addition, we have demonstrated that MSM could exert some protective effect on oxidative and inflammatory exercise-induced injury.