Two experiments were conducted to investigate the effect of dietary energy intake before and after parturition on fatty infiltration in the liver, blood composition and milk protein in cows. In the dry period, ten cows received a diet with 130% of normal energy requirement (experiment 1), while eight cows received a diet with 80% of required energy (experiment 2). At 16 weeks postpartum, the cows were divided into two groups by their level of energy intake, that is 80% and 100% in experiments 1 and 2, respectively. In the experiment 1, cows with an 80% postpartum feeding had average 18% of fatty infiltration in liver cells at 2-week postpartum, while high-yielding cows had more than 40% fat in the liver for a month. However, fatty infiltration was hardly observed in cows fed at the 100% feeding level. In the experiment 2, the ratio of fatty infiltration averaged 12% for cows at 80% feeding level, and 10% for cows at 100%. Cows with more than 20% of fatty infiltration retained over 14% of the pigments after 30 min by the bromusulphalein test, thus showing a depressed liver function. These indicate that extensive mobilization of fatty acid during early lactation may be the prime cause for fatty liver, while overfeeding during the dry period may not result in fatty liver under appropriate feeding conditions after parturition.
The prevalence of calf diarrhea in Japanese Black beef cattle was examined during the period between April 1988 and September 1989 in the northern part of Nagasaki Prefecture. The occurrence of the disease reached its peak in June to August, then decreased gradually, dropping to its lowest level in January. A total of 151 calves died with diarrhea during this same period. Of these 88 (58.3%) calves had whitish diarrhea, 38 (25.2%) watery diarrhea, and the others (16.6%) bloody diarrhea. Sixty-four (42.4%) calves became ill at the age of 0 to 10 days, and 76 calves (50.3%) died within 5 days after the first diarrhea. Fifty-nine fecal specimens of the diarrheal calves were examined for the presence of infectious agents. Enterotoxigenic Escherichia coli was isolated from 31, 42 and 92 day old calves. These three calves also had rotavirus and coccidium. Rotavirus was detected 13 calves (22.0%) 7-92 days old, all except for one excreting whitish feces. Coccidian oocysts were obtained from 32 calves (54.2%), however, only 5 (15.6%) were infected seriously (OPG: 10, 000≤). The eggs of Strongyloides papillosus and Neoascaris vitulorum were detected from six calves (10.2%). A large number of eggs of Strongyloides papillosus (EPG: 28, 600) were found in one of them. Salmonella sp. and Cryptosporidium were not detected in any of the specimens.
A histopathological study was conducted on a total of 214 broiler chickens collected from a certain broiler farm. They consisted of 178 chickens which died before maturity and 36 chickens which were killed due to poor growth or as a result of abnormal legs. Histopathologically, many chickens (153 cases, 71.5%) were found to have arteriolosclerosis in the myocardial layers. Such arteriolosclerosis was found in chickens which were 21 days or older, the incidence of the disease increased with age, and the incidence of severe lesions also tended to escalate as the chicken became older. There have been no reports of chicken cardiac diseases accompanied by cardiac arteriolosclerosis as observed in the present study. Cardiac arteriolosclerosis of this kind can be said to be an unreported, independent disease in terms of its pathology and etiology.
The pathogenesis of pododermatitis circumscripta in cattle was examined. Thirty-two soles of Holstein cattle were observed. Three of them were clinically diagnosed as pododermatisis circumscripta and others appeared clinically normal. Epidermis soleae and corium soleae were observed with a scanning electron microscope. The results are as follows: Not only 3 soles with pododermatitis circumscripta but also 16 having clinically normal soles showed the following abnormal findings: 1. Hyperextension, curvature and hypertrophy on papillae coriales, 2. Vascularization and vasodilation in epidermis soleae and corium soleae and 3. Rhagades in epidermis soleae were observed. From these results, we suppose that these abnormalities are one of the first stage of pododermatitis circumscripta which might be induced from intensive feeding, abnormal hoof length and stress resulting from pregnancy or calving.
The healing process in various suture patterns for experimentally induced perforating teat wound in 32 teats of cows was studied. These were sutured using the Steere-Moody suture (SM), Utrecht method (UM) and Gambee suture (GS). Time course changes were macroscopically, radiographically and histopathologically observed. A marked disorder in the muscle fibers, and a fusion defect in the skin and mucosa and stenosis of the teat sinus due to severe edema were seen on the 10th day after SM and UM suturing. However, very little muscle fiber disorder, perfect fusion and regeneration of the skin and mucosa were observed 5-7 days after GS suturing. Though hematoma and edema in the muscle fibers for all suture patterns in the cross-incision was more severe than that of a longitudinal incision, the healing process in cross-incision was the same as that of the longitudinal incision in GS. The results indicate that the simple interrupted suture pattern, which perforates the mucosa, i.e., GS, in the repair of a perforating teat wound can prevent the formation of teat fistula and/or resultant teat sinal stenosis.
A 2-month-old, female, Japanese cat showed hypothermia, depression and lethargy, and died on the 5th day of the clinical course. Necropsy revealed no significant changes except for a slight swelling of both kidneys. Parts of the kidneys were subjected to a pathological examination. The significant changes found in glomeruli were a crescent formation, localized necrosis and cystic dilation of the glomerular tufts, and fibrin exudation in Bowman's space. Sixty-five to 80 percent of the glomeruli of both kidneys showed an epithelial crescent with more than two-cell thick. Urinary casts and fibrinoid necrosis of the arcuate artery were observed with a mild interstitial inflammatory cell infiltration. Ultrastructurally, the glomerular crescents consisted mainly of epithelial cells. Thickening of glomerular basement membrane was absent. These clinical and pathological findings suggest the present case to be snake venom poisoning.
Paroxysmal atrial tachycardia was observed in a 10-year-old male mixed breed cat with multicentric lymphosarcoma and dirofilariasis. The paroxysms were of a short duration (a few seconds) and occurred once to three times a minute. During the tachycardia the P' waves were somewhat different from the Pwaves of sinus rhythm regarding configuration, and the R-R intervals were the same from beat to beat. A histopathological examination of the heart revealed metastatic infiltrative cardiomyopathy caused by lymphosarcoma and widespread myocardial fibrosis in the right atrium.
Afundamental investigation was performed on a histochemical nitroblue tetrazolium (NBT) reduction test in canine neutrophils. The results suggest that a 15 min incubation period and a 100μg/ml endotoxin concentration are suitable for resting and stimulated NBT reduction tests in canine neutrophils.
We attempted to isolate Listeria spp. from a total of 514 specimens, collected from the body surface of live swine, intestinal contents, the surface of washed carcasses and from the surface of refrigerated carcasses of slaughtered pigs. Listeria monocytogenes was isolated from 7/124 specimens (5.6%) of the washed carcasses, 1/115 specimens (0.9%) of the refrigerated carcasses, and from 1/100 specimens (1.0%) of the body surface. L. innocua was isolated from 2/124 specimens (1.6%) of the washed carcasses, 1/100 specimens (1.0%) of rectal contents, and from 7/100 specimens (7.0%) of the body surface. The fact that the isolation of Listeria spp. was achieved even from the intestinal contents and the body surface of live swine suggested that these could be sources of swine carcass contamination. Eight of nine isolates of L. monocytogenes belonged to serotype 1/2c while the serotype of the remaining one was unidentifiable. In the CAMP test, all the isolates showed a positive reaction to Staphylococcus aureus whereas they were positive for two of the three strains of Rhodococcus equi. Pathogenicity for mice was observed in eight of the nine isolates, but not in the remaining one. Most of the isolates were resistant to various antibiotics, as was reported in other papers to date.