Corynebacterium folliculitis in a horse

A 7-year-old Thoroughbred was examined for evaluation of mildly pruritic multiple skin lesions that had progressed from nodules to alopecia and crusts. Folliculitis caused by Corynebacterium pseudotuberculosis was diagnosed by bacterial culture. Oral treatment with a trimethoprimsulfadiazine paste resulted in resolution of all lesions, with normal hair regrowth.     

Factors associated with outcome following treatment of horses with septic tenosynovitis: 51 cases (1986-2003)

OBJECTIVE: To identify factors associated with outcome (ie, survival and return to function) following treatment of horses with septic tenosynovitis. DESIGN: Retrospective case series. ANIMALS: 51 horses with septic tenosynovitis. PROCEDURES: Information was obtained from medical records and through follow-up conversations with owners. Factors analyzed for an association with outcome included affected limb, etiology, duration of clinical signs prior to examination, presence of complications, primary treatment, secondary treatments, number of surgical procedures, and hospitalization time. RESULTS: Concurrent complications were identified in 41 (80%) horses. The primary treatment consisted of through-and-through lavage in 26 (51%) horses, tenoscopy in 20 (39%), and tenosynoviotomy combined with lavage in 5 (10%). Forty (78%) horses were discharged, and 37 (73%) survived at least 1 year after surgery; 21 of the 37 (57%) returned to their previous or a higher level of performance. Percentages of horses that survived 1 year after discharge and percentages that returned to their intended use did not vary significantly among treatments. Horses with tendon rupture or sepsis of an adjacent joint were significantly less likely to survive. Horses with tendon injury or pannus were significantly less likely to return to their intended use. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that various factors were associated with outcome in horses with septic tenosynovitis. However, surgical technique was not found to be associated with survival rate or rate of return to intended use.     

Isolation of bovine herpesvirus-3 from African buffaloes (Syncerus caffer)

Eleven virus isolations were made from the blood of 45 free living healthy African buffaloes by long term cocultivation of their leucocytes with bovine thymus or spleen cells. The isolates were indistinguishable from each other or from herpesviruses isolated from a severely ill buffalo calf and from a dead buffalo. These viruses possessed the characteristics of the bovine herpesvirus-3 (BHV-3) group and were indistinguishable by serology and restriction endonuclease analysis from the BHV-3 type strains Movar 33/63 and DN599. There was a 93.6 per cent prevalence of indirect immunofluorescent antibody to BHV-3 in the sera of 94 buffaloes in the sample population. No clinical signs or viraemia were detected in five cattle inoculated with 10(8.7) log10 TCID50 of the isolate from the sick buffalo calf. Two of three cattle hyperimmunised with this virus resisted challenge with malignant catarrhal fever herpesvirus, which proved fatal for the other immunised animal and for three control cattle.     

Vascular ring anomaly with coarctation of the aorta in a cat

A 13-week-old, entire male domestic shorthaired cat was presented with a nine-week history of regurgitation following the ingestion of food. A diagnosis of a vascular ring anomaly with coarctation of the aorta was based on clinical signs, angiography and echocardiography. Surgical exploration via a right lateral thoracotomy confirmed the existence of a persistent right aortic arch with right ligamentum arteriosum, aortic coarctation and an aberrant left subclavian artery. Following the surgical transection of the aberrant left subclavian artery, the cat made an uneventful recovery, showing normal swallowing function with no evidence of regurgitation. Twelve months after surgery, the cat had no special dietary requirements and remained clinically normal.     

Effect of induced hypomagnesaemia on the toxicity of imidocarb in calves

The hypothesis that the toxic effects of imidocarb mediated by reduced cholinesterase activity might be intensified by hypomagnesaemia was tested in calves. Hypomagnesaemia was induced in 12 males (50 kg) using an artificial milk based on a commercial nondairy coffee creamer. Although plasma magnesium levels reached 0.33 mmol litre-1 in two weeks no clinical signs were detected. In 12 control calves a daily magnesium supplement of 0.6 g was inadequate although the published requirement is 0.45 g; it was raised to 1.2 g to keep plasma magnesium normal. Lighter calves developed hypomagnesaemia more readily and fast-growing calves had lower plasma urea concentrations. Plasma calcium, but not plasma magnesium, showed significant positive correlation with plasma albumin. The only statistically significant effects of hypomagnesaemia were slight elevations of white cell count and plasma sodium. The hypomagnesaemic and normomagnesaemic calves were divided into two equal groups and treated with 3.3 mg kg-1 of imidocarb dipropionate or a placebo. The drug produced the expected clinical signs of mild toxicity and depression of cholinesterase but no other adverse effects. Transient slight depressions of plasma calcium and potassium concentration, a transient rise of plasma sodium and elevation of creatine kinase occurred. None of the effects of imidocarb treatment was intensified by hypomagnesaemia except, perhaps, constriction of the pupils; generally, hypomagnesaemic animals were affected less.     

Quantifying badger exposure and the risk of bovine tuberculosis for cattle herds in county Kilkenny, Ireland

The objectives of the study were to quantify the levels of badger exposure for cattle and to test the hypothesis that increased badger exposure does not increase the risk of bovine tuberculosis (BTB) in a herd. Information that became available from the targeted removal of badgers over the study period, and from a badger-removal project in county Kilkenny, during 1996-1999 was used. The specific location of cattle within each farm, and the length of time that cattle spent in each farm field during the grazing season, and in the barnyard during winter, was used to build an exposure coefficient to quantify the amount of badger exposure that cattle encountered either on pasture or in the barn. The study design was a matched case-control study in which the control herds were selected using incidence density sampling. During the 4-year study period, 543 badgers were removed and of these 96 badgers were classified as tuberculosis positive; 96 BTB herd breakdowns occurred. There was a significant association between case herds and having a higher badger sett exposure coefficient during 1996-1998. No significant association between case herds and having a higher exposure coefficient based on the number of badgers, or the number of tuberculous badgers, during September 1997-December 1999 was found.     

Characterization of antibiotic-resistant bacteria in rendered animal products.

Antibiotics are used in food animal production to treat diseases and also to improve performance. Antibiotics are not used on all farms, and antibiotic resistance is occasionally found on farms that do not use antibiotics. Rendered animal protein products are often included in poultry feeds and could potentially serve as a source of antibiotic-resistant bacteria. One hundred sixty-five rendered animal protein products from cattle, poultry, and fish were aseptically collected from poultry feed mills. Fifty-five percent of the poultry meal samples had detectable levels of gram-negative bacteria ranging from 40 to 10,440 colony-forming units/g of sample. Poultry meal and meat and bone meal had the greatest number of samples with bacteria resistant to five or more antibiotics. A high percentage of feed samples (85%) contained bacteria resistant to amoxicillin, ampicillin, clavulanic acid, or cephalothin, whereas few samples contained bacteria resistant to ciprofloxacin, kanamycin, or trimethoprim/sulfamethoxazole. Acinetobacter calcoaceticus, Citrobacter freundii, and Enterobacter cloacae were the most commonly isolated antibiotic-resistant bacteria. Isolation for Salmonella was also performed, with 14% of the meat and bone meal samples containing Salmonella sp. Only one of the meat and bone meal isolates, Salmonella livingstone, was resistant to five or more antibiotics. Many of the antibiotic-resistant bacteria contained integrons, genetic elements that mediate multiple drug resistance.     

Accuracy of a discriminant analysis model for prediction of coliform mastitis in dairy cows and a comparison with clinical prediction

We tested an equation, which had been developed previously using discriminant analysis, for predicting whether a cow has coliform mastitis. Variables indicating a high probability of coliform infection included history of previous mastitis in the affected quarter, weakness, clear or white color of milk, water consistency of the milk, swelling of the udder, lack of previous mastitis in other quarters, lack of palpable udder abscesses, and a high body temperature. Application of this predictive equation to 114 cows with mastitis to determine if they would have coliform organisms cultured from the affected quarters resulted in an accuracy of 71% (sensitivity = 0.42, specificity = 0.85), compared to an accuracy of 62% (sensitivity = .64, specificity = .61) for cowside prediction by the attending clinicians. Changing the cutoff score of the discriminant rule so that the sensitivity of the discriminant prediction was similar to that of the clinicians yielded an accuracy of 64% (sensitivity = .64, specificity = .64).