The serological relationship of herpesvirus ovis to other herpesviruses and its possible involvement in the aetiology of jaagsiekte.

Cross-neutralization studies showed that 3 different isolates of herpesvirus ovis from cell cultures derived from the lungs of sheep suffering from jaagsiekte were not only identical but were also related to similar isolate made in Scotland. No relationship, however, could be established between herpesvirus ovis and common bovine or equine herpesviruses. Antibodies to herpesvirus ovis were present in roughly 70% of all animals tested and no evidence was obtained for the involvement of the virus in the aetiology of jaagsiekte. On the other hand, the absence of antibodies in sheep sera from Iceland as well as the other data obtained in this study did not exclude involvement of the virus in jaagsiekte.     

Histopathologic evidence for parvovirus infection in dogs

Two dogs kenneled at a commercial establishment died of a disease manifested as severe hemorrhagic diarrhea. Histopathologic findings in both dogs bore a striking resemblance to those typical of feline infectious enteritis. Viral particles resembling members of the Parvoviridae family were observed in the contents of the small intestine of one of the dogs. The disease was similar to the recently recognized canine gastroenteritis associated with a parvovirus-like agent.     

EPIDEMIOLOGICAL AND GROSS PATHOLOGICAL STUDIES OF ONCHOCERCA GIBSONI INFECTION IN CATTLE

SUMMARY A total of 5712 cattle from 62 properties or localities in northern, central and eastern Australia were examined at abattoirs, and the presence of Onchocerca gibsoni infection was related to region, season when slaughtered, and breed, sex and age of slaughtered cattle. Additionally, these features were also related to nodule characteristics determined from macroscopic examination of all nodules in single (left or right) briskets from 1287 infected cattle selected at random from those examined in abattoirs. Infection rate was 86% and number of nodules per brisket was 3.7 ± 4.1 (Mean ± Standard Deviation). When adjusted for other variables infection rates varied from 18% in central New South Wales to a maximum of 96% in north western Queensland. Number of nodules per brisket in cattle from north western Queensland was 9 times greater than in cattle from central New South Wales. Most nodules (70%) were 1–2 cm in diameter and weighed less than 2 g. The occurrence of changes such as calcification and caseation indicated that 20–30% of nodules studied were undergoing advanced degeneration or resolution. More nodules were detected in autumn than during winter or spring and the proportions of nodules which were hard on palpation, or had thick capsules, both increased during the autumn-spring interval. Although inconclusive, breed differences observed suggested that Bos indicus and B. indicus crossbreds had slightly greater resistance to O. gibsoni infection than cattle of British breed. Infection rate and number of nodules per brisket were greater in bulls than in cows or steers but weight of nodules in steers was greater than in other groups. Percentage of animals infected, and nodule prevalence both increased with increasing age but annual increase in nodule prevalence was less in cattle over 5 years than in younger ones, suggesting development of some immunity in mature cattle.     

Effect of different patterns of food restriction from different ages on growth and efficiency of broilers

1. The effect of restricted feeding on performance and carcass characteristics of broilers was determined in three experiments.

2. In the first experiment, removal of food for 8 h/d from 42 to 56 d of age significantly improved food conversion efficiency of broilers on deep litter. Removal of food for 16 h/d or on alternate days tended to cause slower growth and also improved conversion efficiency.

3. In the second experiment, denial of food for 8 h/d did not significantly affect either growth rate or conversion efficiency of caged broilers. Denial of food on alternate days, from 28 d of age, depressed food intake and growth rate. Food restriction decreased dressing percentage regardless of the age of introduction. With 32, 40 or 48 h food denial each 72 h there was a large depression in growth rate and dressing percentage. Carcass dry matter was also less, indicating less carcass fat, when food was denied for 48 h each 72 h.

4. In the third experiment, growth rate of broilers on deep litter was significantly improved by denying food for 8 h/d from 28 d of age, and was significantly depressed by food denial on alternate days. This depression was significantly more severe if restriction started at 28 d rather than at 42 d of age. Conversion efficiency was not significantly improved by denial for 8 h/d.

5. In the last two experiments conversion efficiency was much worse in severe restriction.     

Unsaturated vitamin b(12) binding capacity in human and ruminant blood serum - a comparison of techniques including a new technique by high performance liquid chromatography

A new technique by High Performance Liquid Chromatography (HPLC-gel permeation) shows promise as a tool to separate and quantitate the Unsaturated Vitamin B(12) Binding Capacity (UBSC) of the individual Vitamin B(12) binders in blood serum. This method, although not as rapid as protein-coated charcoal or cellulose separation techniques, is more applicable for use with large numbers of samples than gel filtration. The use of a radioactivity detector to monitor the eluant from the column permitted automation of the method. Comparable results for UBBC and for the UBBC of individual binders were obtained when samples were analyzed by gel filtration and HPLC. The HPLC method proved suitably precise and the recovery of added cyanocobalamin was acceptable. It is proposed that HPLC be the method of choice for measurement of the USBC of binders of Vitamin B(12) in blood serum.     

Potential effects of glucocorticoids on serum iron concentration in dogs

Prednisone was give norally(2mg/kg b.i.d.) to seven healthy mixed breed dogs for 3 consecutive days. Serum iron concentration increased significantly (p < 0.05) from 142 +/- 26 micro g/dl (mean +/- SE) before a drug adminis- tration on Day 0 to a maximum of 307 +/- 47 micro g/dl on Day 2, and returned to the Day 0 value by Day 5. Mean total iron binding capacity did not vary more than 25% from the Day 0 value during the 9 day long study. The percent saturation of transferrin with iron increased from 33 +/- 6% on Day 0 to a maximum of 71 +/- 9% on Day 3. This determination had decreased to 34 +/- 3% on Day 5. No statistically significant changes occurred in these parameters studied in six control dogs that were not given the drug. To determine whether serum iron concentration might be correlated with endogenous serum cortisol concentration, these tests were determined in serum collected from nine dogs at 7 a.m., 3 p.m., and 11 p.m. each day for 3 consecutive days. Serum iron concentration was lower at 7 a.m. (147 +/- 9 micro g/dl) than at 3 p.m. (164 +/- 9 micro g/dl) or 11 p.m. (159 +/- 10 micro g/dl). Likewise serum cortisol was lower at 7 a.m. (1.29 +/- 0.18 micro g/dl) than at 3 p.m. (1.49 +/- 0.19 micro g/dl) or 11 p.m. (1.51 +/- 0.22 micro g/dl). There was a significant positive linear correlation between serum iron and serum cortisol concentrations when they were compared using mean values for each dog. From these studies, it appears that exogenously administered glucocorticoids and endogenous increases in serum cortisol concentrations may result in increased serum iron concentrations in dogs.