Escherichia coli sepsis and endotoxemia in conscious young pigs

In conscious pigs the influence of intravenous infusion of live E. coli (7×10⁸/kg), of the equivalent amount of endotoxin (20 g/kg) or of a high dose of endotoxin (2.5 mg/kg) on the hemodynamic, clinical and pathological parameters and on survival rate was studied. E. coli and endotoxin infusion resulted in pulmonary hypertension, systemic arterial hypotension, a decrease in cardiac output and an increase in heart rate. Clinical signs were characterized by respiratory and nervous disturbances, whereas necropsy revealed hemorrhages and edema in several organs. Although these findings were similar in the three groups, a marked difference in lethality was observed. Infusion of E. coli or of the high dose of endotoxin resulted in a significant mortality, whereas all pigs survived the infusion of the low dose of endotoxin. This suggests that the lethal pathophysiological mechanisms may only become activated when a sufficient amount of endotoxin is released into the circulation.     

Bovine and canine acute phase proteins

Acute phase proteins are serum proteins which increase in concentration during the acute phase response to inflammation or infection. The response occurs in all animals, but in different species the response of individual proteins can be significantly different. Of the numerous acute phase proteins which have been identified in humans, a number have been examined in cattle and dogs but usually on an individual basis with little reference to their part in the acute phase response. Biochemical, physiological and clinical investigations into haptoglobin, fibrinogen, ₁-proteinase inhibitor, ceruloplasmin, seromucoid and C-reactive protein of cattle and dogs have therefore been reviewed with the emphasis on their role in this response to tissue damage.     

Bile duct obstruction secondary to chronic pancreatitis in seven dogs

Seven icteric dogs were determined to have bile duct obstruction secondary to chronic pancreatitis. All dogs had histories of intermittent vomiting and diarrhea. Alkaline phosphatase and alanine aminotransferase activities and total bilirubin concentrations were markedly elevated. Diagnosis was based on exploratory laparotomy and histological examination. Each dog had a 3 to 10 cm mass in the body of the pancreas and obstruction of the common bile duct. Three dogs treated with pancreatectomy, gastrojejunostomy, and cholecystojejunostomy died within five weeks. Three dogs treated with conservative surgical procedures were alive at 8, 16, and 26 months postoperatively. One dog was euthanized because of suspected neoplasia. Hepatic enzyme activity and bilirubin levels decreased markedly in the surviving dogs. Histological examination of the pancreatic masses indicated chronic pancreatitis. Hepatic biopsies revealed evidence of cholestasis. Chronic pancreatitis should be included in the differential diagnoses of icterus, bile duct obstruction, and masses in the pancreas.     

Comparison of penicillin, oxytetracycline, and trimethoprim-sulfadoxine in the treatment of acute undifferentiated bovine respiratory disease

Penicillin, oxytetracycline, and a trimethoprimsulfadoxine combination were compared as first choice antibiotics for the treatment of acute bovine respiratory disease in weaned beef calves. There was no statistical difference in the mortality losses due to respiratory disease; however, the case fatality rate in the trimethoprim-sulfadoxine treatment group (3%) was markedly lower than in the penicillin (10%) and oxytetracycline (8%) treatment groups. The trimethoprim-sulfadoxine group also had statistically fewer treatment days compared to the penicillin and oxytetracycline groups (p < 0.05). Inclusion of mortality costs in the calculation of treatment costs demonstrated that treatment of the trimethoprimsulfadoxine group was appreciably less costly than treatment of the other groups. Temperature response abnormalities, defined as either an elevation in temperature or a failure of temperature to drop from one treatment day to the next, were associated with a relapse rate of approximately 50%. In vitro antibiotic sensitivity testing of Pasteurella haemolytica isolated from pretreatment nasal swabs was not a useful predictor of treatment success of antimicrobials.     

Fatty acid composition of broiler abdominal fat as influenced by temperature,diet, age and sex

1. Two environmentally controlled houses at 21°‐30°‐21°C (HT) and 21°C (LT) were used to study the effect of temperature on fatty acid composition of the abdominal fat of male and female broilers fed 13.8 and 13 MJ ME/kg diets and slaughtered at 34 and 54 d.

2. Extracts from the abdominal fat of 160 carcases and of the experimental foods were analysed for fatty acids by gas liquid chromatography.

3. Birds reared in HT had a significantly lower proportion of polyun‐saturated fatty acids (PUFA) in their abdominal fat between 34 and 54 d than birds in LT. The depot fat contents of oleic, linoleic and linolenic acids were all reduced by HT at 54 d.

4. For broilers slaughtered at 54 d, saturated fatty acid (SFA) content was much higher in females at high temperatures than in males while at low temperatures PUFA, especially linoleic, was much lower in males than in females.

5. Early finishing of broilers is advantageous from the viewpoint of fatty acid composition because the PUFA/SFA ratio declines significantly with age regardless of temperature.     

Physiological effects of arginine vasotocin and mesotocin in cockerels

1. The effects of continuous infusion of 0.1, 1.0 and 10.0 mU/min/kg body weight of arginine vasotocin (AVT) or mesotocin (MT) on cardiovascular and thermoregulatory responses, on plasma osmolality and ionic composition and on plasma concentrations of AVT, MT, prolactin and aldosterone, were investigated in conscious White Leghorn cockerels.

2. Neither of the peptides, at any dose, affected cardiovascular functions, plasma ions and osmolality. Infusion of MT at the rate of 10 mU/min/kg body weight increased respiratory rate. Both peptides at doses of 1 and 10 mU/min/kg reduced the temperatures of the comb and shank but had no effect on the skin and cloaca.

3. Doses of 0.1 and 1.0 mU MT/mu/kg reduced plasma aldosterone and at 10 mU/min/kg increased plasma AVT. At any given dose MT had no effect on plasma prolactin. AVT at 0.1 and 1.0 mU/min/kg of AVT reduced plasma MT. AVT at 1.0 mU/min/kg increased plasma prolactin and at 10 mU/min/kg reduced plasma aldosterone.

4. During saline infusion, plasma MT was positively correlated with plasma AVT and negatively correlated with respiratory rate and cloacal temperature. Plasma AVT showed a positive correlation with plasma MT and aldosterone and a negative correlation with respiratory rate and skin temperature.

5. During saline infusion, there was no significant correlation between cardiovascular functions, or plasma osmolality and ionic composition and plasma MT or AVT.

6. The present study suggests that interrelationships between circulating concentrations of AVT and MT do exist and that AVT affects