Ovarian activity and uterine involution of 34 postpartum dairy cows were investigated following the intrauterine administration of oxytetracycline (500 mg per tablet). The cows were divided into six groups by treatment: group A (n=6), no tablet; group B (n=6), two tablets within six hours after calving; group C (n=6), four tablets within six hours after calving; group D (n=6), two tablets at 24 hours after calving; group E (n=6), four tablets at 24 hours after calving; group F (n=4, retained placenta), four tablets within six hours or at 24 hours after calving. The following results were obtained: 1) No significant defferences were detected in the times of the first corpus luteum recognition and estrous return among the six groups. 2) Involution times of uterine width of the pregnant side in groups B and E, and cervical width in groups C and E were significantly earlier (P< 0.05) than those of group A. 3) Most of the lochiae on day 1 (calving day=day 0) to day 3 in groups B, C, D and E were lighter in color than those of group A, but all lochiae on and after day 3 in group F changed to dark red. 4) Bacterial counts in the lochiae of groups B and C fluctuated slightly for two days following the administration. However, a decrease in bacterial number in groups D and E was evident for one or two days. 5) No peculier lochial odor due to retained placenta could be detected in group F.
The recent increasing incidence of gangrenous mastitis led us to determine the content of endotoxin derived from Gram-negative bacteria in milk from cows with subclinical mastitis. Also, as to bacterial inhibitors in milk presenting pseudoreaction via a paper disc method for the detection of antibiotics, contents of antibacterial lactoferrin and lysozyme in milk were determined in order to examine their possible involvement therein. The results revealed a significant increase in endotoxin content for CMT+++ compared with CMT--++ and an increase in the degree of contamination due to Gram-negative bacteria. With the paper disc method, it was also revealed that milk with a high degree of CMT aggregation formed an inhibitory circle, and that lactoferrin was more responsible than lysozyme. The above results suggest the contamination due to Gram-negative bacteria to be progressive in subclinical mastitis, indicating the importance of counter measures, if any, in controlling the mastitis. It was also recognized that antibacterial substance such as lactoferrin increased in milk from subclinical mastitis, leading to some antibiotic pseudoreactions.
A case of renal failure with hyperparathyroidism in the dog is reported. The case involved a 6-year-old male German Shepherd dog with a history of continuous vomiting. Laboratory examinations revealed that blood urea nitrogen, serum creatinine and inorganic phosphorus were significantly increased, and calcium was markedly decreased. In addition, aplastic anemia was also confirmed. Histopathologically, interstitial nephritis and crystals similar to those of calcium oxalate in renal tubules, as in cases of ethylene glycol poisoning were demonstrated. The parathyroid glands were enlarged due to an increase of chief cells, and the diarthrodical cartilage and synovialis were necrotic at the articulation of the rib and costal cartilage. These clinicopathological and histopathological findings supported a diagnosis of renal failure with hyperparathyroidism.
Extremely elevated serum potassium levels were detected in a healthy Shiba breed dog and a mixed Shiba breed dog with pyometra. They received no drugs prior to blood examination, and had normal ACTH stimulation test results and BUN concentration. Pseudohyperkalemia, secondary to high potassium erythrocytes, was diagnosed in these dogs by measuring red cell potassium content. Secondary, red cell potassium and sodium content were measured in another 16 Shiba breed dogs and 18 nonindigenous pure breed control dogs to know the frequency of high potassium erythrocytes in Shiba breed dogs. Four of 16 (25%) Shiba breed dogs had high potassium erythrocytes. On the other hand, red cell potassium content of the remaining 12 Shiba breed dogs that had low potassium erythrocytes was significantly (p<0.001) higher than that of the control dogs, whereas there were no significant differences in sodium content between these two groups. We could not make clear the cause of this difference in potassium content.
With the view of clarifying sources and routes of contamination of foods with L. monocytogenes, an actual survey was made of cow and pig carriers brought to the Tokyo Metropolitan Shibaura Abattoir and of the contamination of carcases in the course of the meat processing. The rate of detection of L. monocytogenes from bovine intestinal contents was 2.3% compared with 0% for pigs. The rate of contamination of carcases with L. monocytogenes was 6.7-10.0% for cows and 1.7-30.0% for pigs, depending upon the stages of the processing; it was highest for swine carcases brought in from other abattoirs. Meat processing utensils such as knives and chopping-boards as well as employee's fingers showed a rate of detection of 14.3-31.0%, suggesting their responsibilities for the contamination of the meat. On the other hand, it was revealed that bovine carcases stored at-1-0°C for one day had more than a 50% reduction rate in the detection ofL. monocytogenes. In this survey, L. monocytogenes isolated from bovine intestinal contents and carcases, swine carcases and meat processing utensils was classified into 7 serotypes, including 4b and 1/2b, which have frequently been isolated from patients with listeriosis.