An outbreak of lymphadenitis associated with Stenotrophomonas (Xanthomonas) maltophilia in Omani goats.

Stenotrophomonas maltophilia is a commonly isolated organism from human clinical specimens and is gaining significance as a pathogen in immunocompromised patients and nosocomial infections. In most cases it is difficult to establish the source of human infections. In veterinary medicine, S. maltophilia is not generally considered a primary pathogen. In the present study, we report the occurrence of 16 cases of caprine abscess from which S. maltophilia was isolated in pure culture from 15 animals. In six animals, the abscesses were confined to the pre-scapular lymph nodes but in the remaining nine, the cutaneous abscesses were multiple and extended from the neck to the inguinal area. The possibility is suggested that goats in Oman, which often live in close proximity to humans, might potentially serve as a reservoir of infection.

Ultrastructural observations on the platelets of the Arabian tahr (Hemitragus jayakari).

The ultrastructure of platelets was studied in specimens of peripheral blood from 18 healthy adult Arabian tahrs (Hemitragus jayakari). The platelets were characterized by their extreme polymorphism. The number of alpha granules, typically one to six per cell, was considerably less than that reported for most animal platelets. Similar to humans, the platelets of the Arabian tahr had nucleoids within the alpha granules. However, nucleoids were not a consistent finding. One or more electron-dense granules, most commonly contained within clear vesicles, was commonly observed. A unique feature was the lack of an open canalicular system, which is considered a hallmark feature of this cell type in most mammalian and reptilian platelets.

Observations on haemoglobin types in three breeds of Omani goats.

Haemoglobin (Hb) types were studied in three breeds of Omani goats, Batinah (n = 22), Jebel Akhdar (n = 27) and Dhofari (n = 85). Type A was the only adult Hb observed in adult Batinah and Jebel Akhdar goats. In contrast, only 34% of the Dhofari goats were homozygous for Hb A, while 66% were heterozygous for Hb A and Hb B. Dhofari goats with type AB could further be differentiated into those with approximately 67% type A and 33% type B and those with approximately 33% type A and 67% type B. None of the goats was homozygous for type B. Seventeen kids observed from birth exhibited different levels of fetal Hb, dependent upon whether they developed the adult phenotype AA or AB. Kids that became homozygous for type A were born with approximately 90% Hb F and 10% Hb A. In contrast, goats that developed the heterozygous AB phenotype were born with only 30-60% Hb F, the remaining Hb being types A and B. These findings are not in accordance with previous reports that kids are born without any adult Hb. Hb F was no longer detectable in any of the three breeds of goats at 49 days of age. There was no evidence of Hb C, the pre-adult form of Hb.

Atypical outbreak of caprine cryptosporidiosis in the Sultanate of Oman.

An outbreak of cryptosporidiosis occurred in goats ranging in age from two days to adult, on a well-managed closed farm. None of the other animals on the farm, including sheep, cows and buffalo, were affected. Morbidity approached 100 per cent in goats less than six months of age. Despite intensive supportive care, 238 goats died, ranging in age from two days to over one year. Cryptosporidia were detected in large numbers in the intestinal contents of dead animals and in faecal smears of animals with diarrhoea. Massive numbers of the organisms were also demonstrated histopathologically and by electronmicroscopy, and no other significant pathogens were detected. The outbreak was unique in terms of the extreme virulence of the organism, its apparent species-specificity, and the shedding of the organism by animals over four weeks of age.

An abattoir survey of caprine liver diseases in the sultanate of Oman.

The examination of 675 caprine livers from a slaughterhouse in the Greater Muscat area in the Sultanate of Oman revealed that 63 (9.3%) exhibited gross pathological changes leading to condemnation of this organ. Forty of these livers (71.4%) exhibited one major abnormality, whereas the remaining 28.6% had two or more lesions. The most frequently occurring disorder was diffuse hepatic lipidosis (4.0%), followed by bacterial associated abscesses (2.4%), cysticercosis (1.9%), and eosinophilic granulomata (1%). Although the cause for the hepatic lipidosis was not determined it appeared to be a reversible condition based on the absence of degenerative nuclei within the affected hepatocytes. Conditions observed in only a single liver were subcapsular (non-parasitic) cysts, focal necrosis, micronodular cirrhosis, extensive bile duct proliferation and diffuse haemorrhage.

Hepatic lipidosis associated with cobalt deficiency in Omani goats.

Livers from 36 of 684 (5.3%) apparently healthy goats examined at an abattoir in the greater Muscat area of Oman exhibited gross pathological findings characterized by extremely pale, friable, fatty livers encompassing the entire organ. Histopathologically, diffuse hepatic lipidosis and occasional bile duct proliferation were observed. Periodic acid Schiff-positive, diastase-resistant pigment was observed in the macrophages lining the sinusoids. These histopathological lesions were consistent with those characteristic of ovine white liver disease. Cobalt analysis revealed that normal livers had six times more cobalt and a 3-fold less fat content than those measured in the fatty livers. This is the first report of an association between cobalt deficiency and hepatic lipidosis in Omani goats.

The ultrastructural morphology of the camel eosinophil.

The ultrastructural morphology of the eosinophil was studied in specimens of peripheral blood from normal adult camels and those with eosinophilia. Specific granules were extremely polymorphic. The specific granules exhibited the basic structure of an electron-dense crystalloid core surrounded by a lighter, homogeneous matrix. The crystalloid cores were extremely variable in size and shape, often were segmented and demonstrated a variety of lamellated patterns that were transverse, longitudinal or concentric to the long axis of the core. It was not uncommon to observe multiple crystalloid cores in a single granule. In addition to large specific granules, microgranules and specific microgranules were observed. The extreme polymorphism of the specific granules and variety of lamellated patterns differentiate camel eosinophils from those of other species.