Ichthyosis fetalis in a cross-bred lamb.

BACKGROUND: Ichthyosis is a dermatological disease characterized by varying degrees of generalized hyperkeratosis and alopecia. Two congenital forms of ichthyosis are recognized in animals: fetalis (IF) and congenita. The disease occurs rarely in cattle, swine, dogs, chickens and a goat; it has not been reported in sheep. HYPOTHESIS/OBJECTIVES: To provide clinical, laboratory and pathological assessments of a case of IF in a cross-bred lamb. ANIMALS: A male cross-bred lamb. RESULTS: Physical examination revealed apathy, fever, ectropion and eclabium. Generalized thickening and scaling of the skin was noted; this was most severe on the face, ears, inner thighs, limbs and perineum. Deep fissures and wounds were present on the hind limbs and forelimbs. The lamb was monitored for 75 days. During this period, lesions progressed and occasionally obstructed the nostrils and increasingly made it difficult for the lamb to flex major limb joints. Postmortem findings included severe epidermal thickening, multiple subcutaneous abscesses, ectropion and corneal scars. Histological findings revealed diffuse orthokeratotic hyperkeratosis, follicular keratosis, irregular epidermal hyperplasia and atrophy of the sebaceous glands. Serum vitamin A concentration was within the normal range for the species. CONCLUSIONS AND CLINICAL IMPORTANCE: This case report describes a case of presumptive ichthyosis fetalis in a lamb. Greater awareness by practitioners is required for this disease to be included in the differential diagnosis of dermatopathies in this species.

Toxicity of Gossypol from Cottonseed Cake to Sheep Ovarian Follicles.

Gossypol, a polyphenol compound produced by cotton plant, has proven reproductive toxicity, but the effects of gossypol on sheep ovaries are unknown. This study was aimed to determine the in vitro and in vivo effects of gossypol on the ovarian follicles of sheep. This trial was divided into two experiments. In the first one, we used twelve non-pregnant, nulliparous, Santa Inês crossbred ewes, which were randomly distributed into two equal groups and fed diets with and without cottonseed cake. Feed was offered at 1.5% of the animal's body weight for 63 days. The concentrations of total and free gossypol in the cottonseed cake were 3.28 mg/g and 0.11 mg/g, respectively. Throughout the trial period, no animal showed clinical signs of toxicity and no effects on body weight were observed. However, there was a significantly lower number of viable ovarian follicles (20.6%) and higher number of atretic follicles (79.4%) in the gossypol-fed sheep compared to the control (85.1 and 34.9%, respectively). These findings were observed at all stages of follicular development. In the second experiment, eight ovaries from slaughterhouse were cultured with different concentrations of gossypol acetic acid (0, 5, 10 and 20 µg/mL) for 24 hours or seven days. The in vitro action of gossypol resulted in a significant decrease in viable ovarian follicles, especially the primary and transition follicles, and a significant increase in the number of atretic follicles after 24 hours of culture. These follicles were greatly affected when cultured with gossypol for seven days. It is concluded that gossypol present in cotton seeds directly acts on ovarian follicles in sheep to increase atresia.