Dorsal Approach to the Caudal Pelvic Canal and Rectum Effect on Normal Dogs

A dorsal surgical approach to the perineal area and rectum was made on 10 healthy, adult dogs. The rectococcygeal muscle was incised and the levator ani and external sphincter muscles were separated to the level of the caudal rectal nerve. All dogs were clinically normal throughout a 3 week postoperative observation period.     

Observations on spiral deviation of the penis in beef bulls

Premature spiral deviation of the penis was investigated in 1083 British breed beef bulls in 42 herds in Victoria (35) and Western Australia (7) by means of the serving capacity test. The herd prevalence was 60%. The prevalence of the defect at the initial test for all bulls was 10%. The prevalence in 635 polled bulls was 16% compared to a prevalence of 1 % in 448 horned bulls. The breed prevalence and the number of bulls tested per breed was Red Poll 27% (15), Murray Grey 25% (4), Poll Shorthorn 21 % (34), Angus 17% (415), Poll Hereford 10% (167) and Hereford 1 % (448). The difference between the last 2 breed types was highly significant (P<0.001). The prevalence of the defect increased from 0 to 30% over 9 years in one Victorian herd. The age of affected bulls varied from 2 to 11 years with most affected bulls aged from 3 to 6 years. Common ancestry was found between affected bulls in Western Australia, providing circumstantial evidence that it may be an inherited defect. None of the 103 affected bulls examined in this study had suffered obvious injury to the penis or prepuce. Eighty per cent of 56 affected bulls from Victoria had low serving capacity. Four bulls (2 from each state) with moderate to severe spiral deviation of the penis attained pregnancy rates of 43%, 33%, 3% and 3% respectively, in single sire mating trials. Recommendations for culling defective bulls are presented, based on the herd prevalence and severity of the defect in individual bulls.
It is concluded that bulls with moderate to severe spiral deviation of the penis have reduced fertility and remain permanently affected. The serving capacity test is a valuable diagnostic test for this serving defect in unhandled beef bulls. It is a common, although frequently undiagnosed disorder of polled beef breed bulls in Australia.     

Genetic resistance to Leukosis virus infection: effects on mortality and egg production in Leghorn hens

The influence of genotypic differences in resistance to infection from Lymphoid Leukosis (LL) on mortality and egg production was studied in three pairs of sublines. One subline of each pair had been selected for resistance and the other for susceptibility to infection. At 10 months of age, almost no hens with neutralising antibodies against LL were found in the resistant sublines, while in each susceptible subline more than 40% of the hens had LL antibodies. At 21 months of age, very few hens of the resistant sublines had group-specific (gs) antigen in their eggs. Susceptible sublines differed considerably in this respect, from 81% gs antigen-positive hens in one subline to 9% or no positive hens in the others. On the whole, the susceptible sublines had 6% higher mortality during the laying period (8 months) but the size of the difference was influenced by vaccination against Marek's disease (MD) and varied considerably between pairs of sublines. Significant interactions between strain and genotype of resistance to LL infection were observed for mortality from "other causes" in hens vaccinated against MD, as well as for mortality from "Leukosis" and from "MD" in non-vaccinated hens. The average rate of lay from 1 to 8 months was 8% lower in susceptible hens. In the subline with the highest frequency of eggs containing LL group-specific antigen in the albumen, the reduction of laying rate was twice as large as in the other susceptible sublines.     

An automated micro-method for the enzymatic determination of D-B-hydroxybutyrate in ruminant plasma

1. An enzymatic ‘reaction rate’ micro-method for the rapid routine estimation of D-B-hydroxybutyrate (D-B-HOB) in ruminant plasma, using an I.L. Multistat III centrifugal analyzer, is described.
2. Reaction conditions were optimized to give a linear response for plasma D-B-HOB concentrations between 100 and 2500 μmoles per litre, at 30°C and pH 9.0.
3. For the standardized method the within-run and between-run coefficients of variation for deproteinised ovine plasma were consistently less than 3.5%.
4. There was good agreement between plasma concentrations obtained by the present method and both original U.V. end-point technique (r=0.927b=0.950) and a colorimetric end-point procedure (r=0.937. b=0.879).
5. Utreated ovine and bovine plasma consistently exhibited high ‘blank’ activity and this was directly correlated with plasma lactate dehydrogenase (LDH) activity in both species (r=0.971; p<0.001 and r=0.949; p<0.001 respectively). The distribution of LDH activity in man was similar to sheep but, contrastingly, non-specific interference was extremely low in human plasma and unrelated to LDH. Horse, chicken and rat had negligible ‘blank” activity and comparatively low LDH levels. In both cattle and sheep non-specific interference was abolished by perchloric acid precipitation. In the sheep subtraction of ‘blank’ activity gave D-H-HOB concentrations for untreated plasma comparable to those in deproteinised samples. However, in the bovine, D-B-HOB levels remained significantly (t=6.44; p<0.001) higher even after ‘blank’ correlation. In contrast to man and other non-ruminants, perchloric acid precipitation is essential in ruminants to avoid false overestimation of plasma D-B-HOB levels.
6. Plasma with EDTA as anticoagulant and serum gave concentrations of D-B-HOB approximately 60% lower, than samples containing heparin or oxalate/fluoride. However, heparin was associated with much higher (up to 50%) non-specific NAD rduction than oxalate/fluoride.
7. High levels of acetoacetate (400–1000 μmoles per litre) reduced the recovery of D-B-HOB from ovine plasma by less than 10%. This effect was negated by the inclusion of hydrazine hydrates in the reaction mixture. Perchlorate ion concentrations above 25 μmoles per litre per test dramatically inhibited the assay in ovine plasma, and therefore precipitation conditions must be carefully controlled.
8. Plasma with oxalate/fluoride as anticoagulant showed the greatest stability in storage; 24 hours at room temperature, one week at +4°C and at least one month at ?20°C.

     

The suitability of morphometric parameters of fat cell size for the purposes of animal science research. 1. Cellularity of swine subcutaneous adipose tissue influenced by different fattening ages and graded feed levels

The cellularity of subcutaneous adipose tissue of 108 male castrated pigs (German Landrace) was investigated. The tissue was taken bioptically under anesthetic conditions. The outer and the inner layer of backfat were examined separately, fresh unfixed tissue slices floating in Ringer solution were subjected to microscopic measurements of adipocyte diameters. The animals were kept in feeding experiments, 3 and 2 sectors respectively of growing period were examined (40 kg; 66 kg, 88 kg body mass) divided into 6 and 4 feeding levels respectively for 21 days (0.4; 0.6/0.8; 1.0; 1.2; 1.4 MJ metabolic energy per kg body mass0.75 per day). The inner layer of backfat showed bigger fat cells compared to the outer layer. The average fat cell size was greater for the older and heavier than for the younger animals. The gradation of food administration resulted not in a straight parallel rise in fat cell size but in an effective consequence with respect to the distribution frequency of the dates: The higher the food energy level, the more the accumulation of small fat cells from 10 til 30 microns diameter. These cell fractions succeeded in being signified as typical and important closed population. Other authors also had described these particular cells, i.e. "fat cell clusters" and "VSFC" (= very small fat cells) respectively. An external use of the dates for computer simulation programs resulted in success and manifested the independently gained conclusions. The examinations were performed by support of different branches of literature and the results had to be discussed in front of a wide background of known connections.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of biochemical evidence of congenital nutritional myopathy in two-week prepartum fetuses from selenium-deficient ewes

Muscle damage attributable to selenium (Se)/vitamin E deficiencies is known to develop at birth or later in lambs. The purpose of this study was to determine whether and when muscle damage develops in utero. Thirty pregnant ewes maintained on Se-deficient forages from birth were allotted to 3 equal groups. Half of each group was given a single IM injection of 0.056 mg of Se/kg of body weight, 1 month before parturition. At 3 weeks before parturition, cesarean section-derived fetuses from Se-deficient ewes did not have evidence of muscle damage. At 2 weeks before parturition, fetuses from Se-deficient ewes had biochemical evidence of congenital nutritional myopathy, as evidenced by low blood Se concentration (P less than 0.05) and by increased plasma creatinine kinase (P less than 0.001) and lactate dehydrogenase (P less than 0.01) activities, compared with fetuses from Se-treated ewes. Thus, for optimal protection of fetuses and newborn lambs in Se-deficient areas, Se should be administered to ewes at least 1 month before parturition.     

Infarction of the pons and medulla oblongata caused by arteriolar thrombosis in a horse

Infarction of the pons and rostral medulla secondary to arteriolar thrombosis was documented histologically in a 17-year-old mixed-Arabian female horse. Clinically, the animal experienced a sudden onset of a head tilt and subsequent non-controllable seizures. There was no historical, clinical or histological evidence to suggest the presence of infection of Equine Herpesvirus-1 or the feeding of corn contaminated by Fusarium moniliforme.     

Experimental transmission of a dermal sarcoma in fingerling walleyes (Stizostedion vitreum vitreum)

Dermal sarcoma is a benign skin tumor of adult walleyes (Stizostedion vitreum vitreum) with a suspected viral etiology. A laboratory study was initiated to determine if the tumor could be experimentally transmitted by inoculating young walleyes with materials prepared from tumors from adult fish. Eighty walleye fingerlings were divided into four groups of 20 fish each. Two groups were inoculated intramuscularly at 4 months of age either with live tumor cells or with cell-free filtrates of sonicated tumor cells. The two other groups were used as controls and were inoculated either with cultured cells from normal walleye fry or with tissue culture media. Neoplasms, similar to the dermal sarcoma affecting adult walleyes, were observed after 4 months only in fingerlings inoculated with cell-free filtrates of sonicated tumor cells. Like the tumor affecting wild adult walleyes, the transmitted tumors were restricted to the dermis and originated from the superficial surface of scales. They never invaded locally and never metastasized. The transmitted tumors differed from tumors of adult walleyes in their severity and the absence of osteoid. The multicentric origin of transmitted walleye dermal sarcoma suggests that the virus spreads systemically and that tumor cells are polyclonal. This successful transmission of the lesion, along with the presence of C-type virus particles budding from tumor cells in two of seven tumor-bearing fingerlings, supports a retroviral etiology.