Histomoniasis in Leghorn pullets on a Florida farm

Recurrent outbreaks of histomoniasis in flocks of 4-to-6-week-old white leghorn pullets is reported. In a typical outbreak, 5% of the pullets were stunted and listless with unkempt feathers. Mortality ranged from 2 to 3%, and the cull rate was approximately 2%. Ceca of affected chickens contained caseous cores. Histological examination of the ceca revealed fibrinonecrotic ulcerative granulomatous typhlitis associated with numerous histomonad trophozoites in the cecal wall. The outbreaks of histomoniasis were associated with heavy parasitism of pullets by Heterakis gallinarum. Litter had not been completely removed from the houses for the past 10 years, providing a constant source of Histomonas-infected larvated Heterakis ova.     

Diabetes mellitus induced in a dog after administration of corticosteroids and methylprednisolone pulse therapy

An 8-year-old ovariohysterectomized Chow Chow was referred because of dermatologic lesions diagnosed as pemphigus foliaceus. Intolerance to orally administered corticosteroids necessitated the use of methylprednisolone pulse therapy. One week after treatment, diabetes mellitus was diagnosed on the basis of blood and urine test results. For 3 years after treatment, the dog has remained a well-regulated diabetic. Complete remission of pemphigus foliaceus is maintained by alternate-day, orally administered prednisone (0.5 mg/kg of body weight).     

Prolongation of xylazine/ketamine induced recumbency time with temazepam in horses

Short term anaesthesia induced with xylazine and ketamine was compared to a combination of xylazine, ketamine and temazepam (a benzodiazepine) in six adult horses. Duration of recumbency was significantly prolonged when temazepam was administered with xylazine and ketamine. No significant differences in heart rate, respiratory rate, blood pressure or arterial pH, pCO2 and pO2 were seen between the xylazine and ketamine combination plus temazepam, and xylazine and ketamine combination only treated horses.     

Feedlot performance of Brahman x Angus versus Angus steers during cold weather

Ten Angus and 10 Brahman x Angus F1 steers were used in a 184-d trial to compare feedlot performance during cold weather (-9 to 26 degrees C). Both groups of steers were exposed to the same environment for the same amount of time. All steers were fed for the same number of days regardless of frame score to avoid frame score x environment interactions. Brahman x Angus steers were 30.7 kg heavier (P less than .05) than Angus steers at the start of the trial. Differences in age (Brahman x Angus 40 d younger) for the two breed groups did not affect final live weight or carcass weight. Brahman x Angus steers consumed .2% less feed (P less than .05) as a percentage of BW than Angus steers; however, there was no difference in overall feed efficiency. Angus steers had a higher yield grade, more fat at the 12th rib (P less than .05), and graded 90% Choice; only 10% of the Brahman x Angus were graded Choice. Brahman x Angus steers were taller at the hip (P less than .05) and longer from first rib to aitch bone (P less than .05) and from thoracic vertebrae (T12/T13) to point of hock (P less than .05). Hide thickness determined at the neck, belly, and rump was found to be similar (7.7 mm) between the two groups. Sample hair weight and diameter did not differ between groups. Fiber, fat, protein, and DM digestibility coefficients were similar between groups but Brahman x Angus feces had a higher DM content.(ABSTRACT TRUNCATED AT 250 WORDS)     

Resistance of Pasteurella multocida A:3,4 to phagocytosis by turkey macrophages and heterophils

A virulent field isolate and 2 vaccine strains of Pasteurella multocida A:3,4 were compared for resistance to phagocytosis by turkey macrophages and heterophils, using in vitro assays. The least virulent vaccine strain (M-9) was phagocytosed to a greater degree than was the field isolate or the other vaccine strain (Clemson University). All 3 bacteria differed significantly from each other in the amount of capsular material present as measured by polycationic ferritin labeling and electron microscopy. Removal of the capsule with hyaluronidase resulted in a significant increase in phagocytosis of the field isolate.     

Outer membrane protein profiles of Yersinia ruckeri

The outer membrane protein (OMP) profiles of 135 isolates of Yersinia ruckeri, obtained from nine European countries (100 isolates), North America (23 isolates), Australia (six isolates) and South Africa (two isolates), and including four reference strains, were examined by SDS-PAGE. Outer membranes were isolated by selective solubilisation of the cytoplasmic membrane with 0.5% (w/v) sodium N-lauroyl sarcosinate (Sarkosyl). Outer membrane proteins were stable after in vitro passage and there was no variation in OMP profiles due to colony selection. With the exception of a 39.5 kDa peptidoglycan-associated protein there was also no variation at different stages of the growth cycle. The 39.5 kDa protein was not produced during logarithmic growth phase but increased in abundance as the stationary phase progressed. Interstrain variation occurred in the possession of a 36.5 or 38 kDa heat-modifiable protein and in the possession of peptidoglycan-associated proteins in the molecular weight range 36.5 to 40.5 kDa. Based on variation of these proteins five OMP-types, designated OMP-types 1-5, were identified among the 135 isolates examined. Outer membrane protein analysis was demonstrated to be useful in epidemiological studies of Y. ruckeri.     

Influence of nutrition and body condition on pituitary, ovarian, and thyroid function of nonlactating beef cows

Nonpregnant Hereford cows (n = 70) were used to determine the effect of nutrient intake and body condition on reproductive and thyroid function. Body condition scores (BCS; 1 = emaciated; 9 = obese) of cows averaged 5.0 +/- .2 on July 1, and cows were fed for 4 mo either to lose weight and BCS (thin; n = 22), to maintain weight and BCS (moderate; n = 24), or to gain weight and BCS (fat; n = 24). After November 1, cows received a complete ration to maintain weight and BCS. Cows were slaughtered in December (six thin, eight moderate, and eight fat cows) or the subsequent March (16 cows per group). Before slaughter, cows were given two injections of prostaglandin F2 alpha (PGF) 11 d apart. Six days after the second PGF injection, cows were simultaneously treated with 100 micrograms of gonadotropin releasing hormone (GnRH; i.m.) and 100 micrograms of thyrotropin releasing hormone (TRH; i.v.) and serum samples were obtained. The BCS of cows at slaughter (8 d after PGF) averaged 3.4, 5.3, and 7.1 (P less than .01) and carcass energy content averaged 243, 432, and 714 Mcal (P less than .01) for thin, moderate, and fat cows, respectively. Wet ovarian (P less than .001) and corpora lutea (P less than .01) weights were heavier for fat cows. Content of LH in the pituitary gland and concentrations of thyroxine (T4) in serum after GnRH/TRH were not influenced by nutrient intake or BCS. However, thin cows had greater concentrations (P less than .05) of LH in serum after GnRH/TRH than did moderate or fat cows. We conclude that nutrient intake and body energy reserves of beef cows influenced ovarian function and LH in serum after treatment with GnRH.     

Aortic stenosis: clinical findings in six cats

Congenital aortic stenosis was diagnosed in six cats. Clinical findings included dyspnoea, systolic murmurs with maximal intensity at the left apex or right sternal border, and cardiomegaly with congestive heart failure. Some clinical features of feline aortic stenosis were similar to those observed in cats with hypertrophic cardiomyopathy. Definitive diagnosis was obtained by angiographic imaging of a discrete, consistent subvalvular obstruction, Doppler-echocardio-graphy, or by necropsy. Although, two of the cats were diagnosed at ages older than usually reported, the overall prognosis for cats with aortic stenosis was poor. Four of the six cats died or were euthanased within one year of the onset of clinical signs.     

Rapid infection in market-weight swine following exposure to a Salmonella typhimurium-contaminated environment

OBJECTIVE: To evaluate the possibility of swine becoming infected with Salmonella Typhimurium when housed for 2 to 6 hours in an environment contaminated with Salmonella, similar to a lairage situation prior to slaughter. ANIMALS: 40 crossbred market pigs with an approximate body weight of 92 kg. PROCEDURE: Five trials were conducted (8 pigs/trial) in simulated lairage conditions. Superficial inguinal, ileocecal, and mandibular lymph nodes, cecal contents, distal portion of the ileum, and fecal samples were obtained from each pig after 2 (n = 10), 3 (10), and 6 (5) hours of exposure to an environment contaminated with feces defecated by 10 pigs intranasally inoculated with nalidixic acid-resistant Salmonella Typhimurium (chi4232). In addition, 5 control pigs that were not exposed were also evaluated in the same manner. RESULTS: Feces deposited on the floor by intranasally inoculated swine were mixed with water to form slurry with a resulting load of approximately 10(3) colony-forming units of Salmonella Typhimurium/g of material. Eight of 10, 6 of 10, and 6 of 6 pigs exposed to the slurry for 2, 3, or 6 hours, respectively, had positive results for at least 1 sample when tested for the specific strain of Salmonella Typhimurium. CONCLUSIONS AND CLINICAL RELEVANCE: Pigs can become infected during routine resting or holding periods during marketing when exposed to relatively low amounts of Salmonella organisms in the preslaughter environment. Intervention at this step of the production process may have a major impact on the safety of pork products.