Pharmacokinetic variables of phenolsulfonphthalein (PSP) were determined in sheep after rapid IV injection and IV infusion to steady state. In Suffolk wethers, an average of < 75% of an IV administered dose was eliminated in urine, indicating that measures of systemic clearance overestimate renal clearance in this species. Furthermore, PSP elimination from plasma was more rapid in Suffolk than Rambouillet wethers and, in Suffolk ewes, systemic clearance decreased from mean +/- SD 7.8 +/- 0.3 ml/min/kg of body weight to 4.7 +/- 1.1 ml/min/kg at steady-state plasma concentration of 2.4 +/- 0.3 and 151.3 +/- 31.8 micrograms/ml, respectively. These observations indicate that, similar to that in other species, systemic clearance of PSP in sheep is concentration-dependent and that significant differences may exist between breeds.

An agar gel immunodiffusion (AGID) test was used over a 3-year period to examine 1,871 serum samples from sheep representing 5 Mycobacterium paratuberculosis infected flocks and 4 flocks presumed to be uninfected. Of 1,032 sheep, 31 had positive AGID test results (scoring 1 to 5), and 23 of these 31 were ecropsied. Infection with M paratuberculosis was confirmed by 1 or more of the following findings: observation of typical lesions on histologic examination of sections of ileum or ileocecal lymph nodes, observation of clumps of acid-fast bacteria in mucosal smears of ileum, and isolation of the organism from feces or tissue. False-positive results on AGID testing were not found in sheep from flocks known to have exposure to Cotynebacterium pseudotuberculosis. Diarrhea in infected sheep was observed infrequency; chronic, severe weight loss was the most common sign observed. On histologic examination of tissues from 20 infected sheep, 16 (80%) had diffuse lesions of the ileum and 13 (65%) had acid-fast bacteria in areas of ileal inflammation; 4 had discrete granulomas and peripheral lymphocytic infiltrates in the ileum. Sheep with diffuse lesions tended to have higher mean scores on AGID testing and examination for acid-fast bacteria, compared with those from sheep with more discrete lesions. Bacteriologic culture yielded M paratuberculosis from only 3 sheep with paratuberculosis. On the basis of results of this study, we suggest that the nature of the response to infection with M paratuberculosis may influence the results of diagnostic tests for paratuberculosis, and that AGID testing may be useful to identify M paratuberculosis infection in sheep with chronic weight loss and in flock-screening programs.

Corynebacterium pseudotuberculosis phospholipase D (PLD) significantly affected viability of ovine neutrophils after 24 hours' exposure, This effect was more marked in cells that ingested PLD emulsified in oil. Treatment of neutrophils with PLD significantly (P < 0.05) reduced the ability of these cells to migrate toward activated sheep serum. The PLD was not chemotactic, but it activated normal sheep serum, producing factors that were chemotactic for neutrophils.

A study was designed to compare use of an numerical rating scale (NRS) and a visual analogue scale (VAS) for subjective assessment of lameness, using sheep as a model. The NRS consisted of 5 divisions, 0, 1, 2, 3, and 4; 4 of these divisions (1-4) described lameness. The VAS used a 100-mm horizontal line with vertical bars at either end; one end was labeled 'sound' and the other was labeled 'could not be more lame.' Two independent observers graded lameness in 62 sheep, and between- and within-observer differences were assessed for each scoring system to compare the NRS with the VAS. Results indicated no significant differences between the 2 observers scoring lameness, using either the VAS or the NRS. The scores obtained, using the VAS, were not normally distributed, although differences between scores for the 2 observers were. The NRS scores followed a normal distribution pattern. Investigation of repeated measurement for the same sheep, using both scales, revealed no significant difference between either. A comparison of the NRS and VAS scores made by each observer indicated that although correlation was good (observer 1; r = 0.94; observer 2; r = 0.95), there was not perfect agreement. The maximal NRS score of 4 was associated with VAS values > 68 mm, indicating that the NRS divisions did not reflect equal increases in lameness. The VAS and NRS scores for each observer were highly reproducible, although they were more variable for sheep that were regarded as moderately lame. Results indicate that although the NRS and VAS compared favorably with respect to repeatability, reproducibility, and use by 2 observers, the VAS is inherently more sensitive. In addition, the NRS and VAS should not be used interchangeably.

<p>Determination of the pH and total titratable acidity from rumen liquor was carried out in Australian Merino and Corriedale sheep fed on pasture, in two seasons of the year (winter and summer), in Botucatu City, São Paulo, Brazil. Ruminal samples were collected using a standard tube, from 103 sheep during the winter period (50 Corriedale and 53 Australian Merino) and from 107 sheep in the summer (52 Corriedale and 55 Australian Merino). The results obtained for pH and total titratable acidity in Australian Merino sheep in winter and summer were, respectively 6,69 ± 0,20 and 6,75 ± 0,23, and 26,27 ± 5,02 and 29,24 ± 6.24 units. The results observed in these tests for Corriedale sheep in winter and summer were, respectively, 6,70 ± 0,21 and 6,84 ±0,28, and 27,26 ± 4,82 and 30,40 ± 5,11 units.</p> | <p>Objetivou-se estabelecer padrões de normalidade para a concentração hidrogeniônica (pH) e acidez total titulável do líquido ruminal de ovinos das raças Merino Australiano e Corriedale, criados em regime extensivo de pastagem em duas épocas do ano (inverno e verão), no município de Botucatu, Estado de São Paulo. No invemo foram utilizados 103 animais, sendo 50 ovelhas da raça Corriedale e 53 da raça Merino Australiano e, no verão, 107 animais, sendo 52 ovelhas pertencentes à raça Corriedale e 55 à raça Merino Australiano. As amostras de suco de rúmen foram obtidas através de sonda esofágica. Os resultados obtidos para o pH e a acidez total titulável para os animais da raça Merino Australiano no invemo e no verão foram, respectivamente, 6,69 ± 0,20 e 6,75 ± 0,23, e 26,27 ± 5,02 e 29,24 ± 6,24 unidades. Os resultados observados nessas provas para os ovinos da raça Corriedale, no invemo e no verão foram, respectivamente 6,70 ± 0,21 e 6,84 ± 0,28 e 27,26 ± 4,82 e 30,40 ±5,11 unidades.</p>