Prevalence of Alcaligenes faecalis in North Carolina broiler flocks and its relationship to respiratory disease

In order to assess the role of Alcaligenes faecalis in respiratory disease of broilers, a study was conducted to determine the prevalence of this bacterium in North Carolina broilers and to determine the relationship of A. faecalis infection to clinical disease. Our studies showed that A. faecalis is prevalent in North Carolina commercial broilers during the winter months. Bacteriological examination of turbinates and tracheas revealed that almost 40% of individual birds between 35 and 45 days of age yielded positive cultures; 62% of tested flocks were infected. When present, A. faecalis was usually the predominant bacterium isolated. Furthermore, because of a higher frequency of A. faecalis isolation in broiler flocks with respiratory disease (75% vs. 29% in flocks without respiratory diseases), these studies suggest a causal relationship between this bacterium and clinical respiratory disease.     

Intra-articular tissue response to analytical grade metrizamide in dogs

The effect of analytical grade metrizamide (AM) injected into the canine stifle, for purposes of arthrography, was studied in 12 adult dogs using saline solution as the control solution injected into the contralateral joints. The AM was used at a concentration of 280 mg of iodine/ml and was administered at the dose of 0.3 ml/cm thickness of the stifle joint. For each joint, arthrocentesis was done before and 7 days after injection of either the contrast medium or saline solution. Physical, biochemical, and cytologic examinations were done on the synovial fluid while the synovial membranes and femoral articular cartilages were sectioned, stained, and examined for histopathologic changes. At the 95% confidence level, significant differences in the total and differential mononuclear cell counts were not seen between the AM- and saline solution-injected joints. However, some subtle changes in the synovial membranes were observed. Intra-articular injection of AM or saline solution initiated a mild inflammatory response, the AM causing slightly more response than the saline solution.     

Sewage‐grown algae as a source of pigments for broilers

1. Relative utilisations of xanthophylls in young broilers from diets containing meals prepared from the algae Chlorella and Micractinium and alfalfa meal were determined.

2. Relative utilisation was evaluated from plasma and toe‐web xanthophyll contents, and by visual scoring.

3. The results showed poorer xanthophyll utilisation from algae‐containing diets than from alfalfa meal, but algae meals can be used effectively as pigment sources in poultry diets.

     

An experimental model of chronic renal disease in dogs by infusion of microspheres into the renal arterial circulation

The feasibility of renal arterial infusion of nonbiodegradable microspheres as a model of chronic renal disease in dogs was evaluated. Resin-coated, styrene-divinyl benzene copolymer microspheres were infused into the kidneys of healthy adult Beagles by direct injections of both renal arteries in a single surgical procedure. Injections of 25-microns diameter microspheres had minimal effect on either the clinical status or serum values of the dogs. Histologic examination revealed the majority of the microspheres lodged within the capillary beds of the glomeruli, and little change to the kidneys. However, injections of 50-microns diameter microspheres caused significant increases in serum concentrations of urea nitrogen and creatinine. Histologically, the larger microspheres obstructed afferent arterioles and small arteries, which caused diffuse glomerular necrosis and nephron damage. With doses ranging from 1 to 3 million microspheres/dog, a correlation between the quantity of microspheres injected and severity of renal damage was observed. The optimal dose for producing a model of moderate renal disease was determined to be 1.8 million microspheres/dog (0.9 million microspheres/kidney). During long-term studies, microsphere-injected dogs fed a moderately restricted protein ration remained relatively azotemic, compared with control dogs on the identical ration. During the 5-month postsurgical period, the serum urea nitrogen concentration averaged 18.41 +/- 1.59 mg/dl (mean +/- SE) for the microsphere-injected dogs vs 9.31 +/- 0.38 for the control dogs (P less than 0.001). Similarly, the mean serum creatinine value was significantly higher (P = 0.020) for the microsphere-injected dogs, compared with the controls (1.23 +/- 0.12 mg/dl vs 0.94 +/- 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of footing surface on mounting and other sexual behaviors of estrual Holstein cows

Seven ovariectomized Holstein cows, treated sequentially with progesterone and estradiol benzoate to induce estrus, were used to determine whether cows showed a preference for mounting and displaying other sexual behaviors toward estrual or nonestrual cows tied on dirt or concrete surfaces. Preference tests were conducted in a test area that consisted of equal-sized concrete and dirt surfaces; two cows, designated A and B, were tied on the two surfaces, one on either side. Cows A and B were treated so that on each of four test days both were estrual, only A was estrual, only B was estrual or neither A nor B were estrual. On each test day, five estrual test cows were introduced individually into the test area for two 30-min test periods. During the first test period, tied cow A was on concrete and tied cow B was on dirt, but during the second test period, their positions were switched. Test cows were able to move freely from surface to surface and to interact with tied cow A or B. Estrual test cows spent 21.6 +/- 1.4 min of each 30-min test period on dirt, regardless of the estrual status of the cow tied on concrete or dirt. Mounting activity was 3- to 15-fold greater on dirt than on concrete when there was an estrual cow tied on dirt, regardless of the estrual status of the cow on concrete. Mounting activity was fourfold greater on concrete than on dirt when there was a tied estrual cow on concrete and a tied nonestrual cow on dirt.(ABSTRACT TRUNCATED AT 250 WORDS)     

Salmonella isolated from feeds and feed ingredients during the period 1982-1988: animal and public health implications

The prevalence of Salmonella in southern Africa in farm feeds and by-products of animal origin during 1982-1988 was determined. Salmonella occurred in 5.18% of the farm feed samples and in 9.54% of the by-product samples. Different serovars were isolated, some only once. The findings underestimate the true prevalence of Salmonella in farm feeds and by-products, and is representative of only the most severely contaminated products. The epidemiology of salmonellosis is discussed with special reference to the importance of multiple resistance to antibiotics, the increase in the number of cases of salmonellosis worldwide and "Salmonella free" feeds and foods. More detailed research on the role of farm feeds in the epidemiology of salmonellosis is required. Efforts should be made to increase awareness of the problem, to improve quality management at farm feed production plants and to develop efficient systems to monitor the hygienic safety of feeds and foods.     

Plasma concentrations of cortisol, testosterone, glucose and blood gases in male goats during anaesthesia with pentobarbitone sodium

Fasting for 24 h had no statistically significant effect on cortisol, glucose or testosterone concentrations. A dose of pentobarbitone sodium which induced light anaesthesia resulted in an immediate decrease in cortisol values from 5.0-11.1 ng/ml to 2.2-3.6 ng/ml until waking-this latter event was accompanied by an excessive release of cortisol (up to 16.6 ng/ml). In two out of three goats testosterone concentrations decreased from 4.0-9.0 ng/ml to less than 0.5 ng/ml after pentobarbitone; low values were maintained for 4.5-6 hours. Glucose concentrations were unaffected. Precise doses of pentobarbitone (20 mg/kg or 30 mg/kg) resulted in similar cortisol profiles as above but with higher concentrations achieved upon waking from the higher dose of pentobarbitone. On two out of nine occasions increased PCO2 values were recorded concurrently with increased cortisol concentrations during the period of anaesthesia, suggesting that a sufficiently strong stressful stimulus can break through the pentobarbitone blockade.     

Urethral tumours in dogs

Urethral tumours in 21 dogs are reported. Transitional cell carcinoma was the most frequent presentation. A more deliberate radiographic protocol has enhanced diagnostic ability and has improved presurgical evaluation. The use of a transpubic surgical approach has allowed the direct examination of the affected urethra and excision or resection of focal and diffuse lesions in 10 dogs with periods of remission varying from eight to 22 months. The apparent success of the surgical technique underlines the necessity for early and careful investigation of the dysuric, haematuric case.