Biochemical analysis by SDS-PAGE and western blotting of the antigenic relationship between Leptospira and equine ocular tissues.

The antigenic relationship between Leptospira interrogans, equine cornea and lens was previously noted in our studies. Serum antibodies from horses inoculated with serovars wolffi, pomona, icterohaemorrhagiae, and tarassovi, were able to bind to five antigenic fractions from both cornea and lens, as demonstrated by immunoblotting. These antigens seem to be made up of protein and carbohydrates. After treatment with periodate for cleavage of glycoside ring structures, those fractions kept their condition of target for anti-Leptospira antibodies. Nevertheless, all fractions lost that condition after being subjected to peptide hydrolysis.     

Skeletal muscle protein metabolism and serum growth hormone, insulin, and cortisol concentrations in growing steers implanted with estradiol-17 beta, trenbolone acetate, or estradiol-17 beta plus trenbolone acetate.

Skeletal muscle protein degradation, measured by urinary N tau-methylhistidine excretion, and circulating concentrations of growth hormone (GH), insulin (INS), and cortisol (CT) were monitored in steers before and after implantation with estradiol-17 beta (E2; 24 mg) and trenbolone acetate (TBA; 300 mg). Yearling crossbred steers (n = 43) were randomly assigned to four treatment groups in a 2 x 2 factorial arrangement: nonimplanted controls (C); TBA; E2; and TBA plus E2 (TBA+E2). A subgroup (Block 1) of 16 steers was bled on d -12, 31, and 72 after implanting. Deposition of skeletal muscle protein was markedly increased (P less than .001) by E2 and TBA+E2 treatment. This response occurred mainly within the first 40 d after implantation and declined (P less than .001) in concert with decreasing (P less than .01) concentration of serum E2. Anabolic steroid treatment did not affect the rate of skeletal muscle protein breakdown. There was no apparent relationship between reduced serum CT concentration (linear effect; P less than .01) in TBA-treated steers and skeletal muscle protein degradation rate. Blood concentration and pulse activity of INS were not affected by anabolic steroid administration. Both TBA- and TBA+E2-implanted steers displayed a linear decrease (P less than .05) in serum GH concentration over time, which was similar to C. Lowered mean GH concentration resulted from a reduction (TBA main effect; P less than .05) in pulse amplitude of GH. Unlike TBA, TBA+E2, and C, only E2 maintained serum GH concentrations over time. Although increased muscle protein deposition was evident in TBA+E2-treated steers, an obvious causal relationship between this response and circulating GH, INS, and CT was not revealed. These results do not support the concept that combined androgenic agent and estrogen administration effectively reduce bovine muscle protein degradation by static modulation of circulating endogenous anabolic and antianabolic hormones.     

Oral-dental disease in cats. A feline practitioner's perspective.

The impact and relevance of dentistry in a general feline practice is detailed. Hospital policy and protocol are described for client education, preanesthetic evaluation, dental procedures, and recall programs. A discussion of commonly observed feline dental problems is included.     

Blood types in cattle of Iberian ancestry and in Holsteins at various altitudes.

Gene frequencies of RBC antigens were determined in Holsteins and Colombian (criollas) cattle living at 3,000 m, and in cattle descended from fighting bulls (Vacas de lidia) living at 2,500 m. These frequencies were compared with those of Holsteins, cattle native to Florida (scrub cattle), longhorns, and native cattle from Brazil (caracu cattle) living at sea level. The criollas, Vacas de lidia, scrub cows, longhorns, and caracu are descendants of original Iberian stock introduced to the Americas. We found that despite common ancestry (scrub cattle, long-horns, criollas, and caracu), genetic differences may have been derived through years of demographic isolation. The most remarkable blood-group differences were found in the high prevalence of the B system phenogroup (heritable group of antigenic factors) BQA'G'34 in the Vacas de lidia, and of the S system phenogroup U1H' in these cattle and in caracu. Furthermore, the gene frequencies differed in the Holsteins maintained at moderately high altitude (descended from Holsteins kept at sea level), and may have been reflective of the need to adapt to moderately high altitude and chronic hypoxemic conditions. Blood group polymorphism was found in all groups of cattle, although it was reduced in the Vacas de lidia, possibly because their breeding has been carefully controlled and they appear to be highly inbred.     

Effects of alternative lamb production systems, maternal line, and culling strategy on flock age structure.

The 5-yr attrition of 1/4 (n = 411) or 1/2 (n = 403) Finnsheep (Finn) ewes exposed to terminal sire breeds in either an accelerated or semi-intensive annual lambing system was recorded to test the effects of system and percentage Finn on flock age structure at equilibrium. Ewes were culled for discernible ailments and failure to lamb after two consecutive non-spring exposures in yr 3, 4, or 5 only. Additionally, four progressively more intensive culling strategies for nonconception were practiced in retrospect. Flock productivity (kilograms of lamb weaned per ewe maintained per year) at age structure equilibrium was estimated for all culling strategies. The majority of all systems (cull strategy x lambing system x percentage Finn combination) were composed of ewes less than or equal to 3 yr old. Replacement requirements ranged from 24 to 38% in the accelerated system and 22 to 26% in the annual system. Quarter-Finns yielded greater replacement needs and shorter productive lives in accelerated lambing but fewer replacement requirements and longer productive lives than 1/2 Finns in annual lambing. Replacement requirements greatly increased with culling intensity in accelerated lambing (up to 54% above original levels) but only slightly in annual lambing (up to 8% above original levels). Mean (reproductive) lifetime estimated from fitted Weibull survival curves ranged from 3.1 to 5.1 yr in accelerated lambing and 4.5 to 5.4 yr in annual lambing. Increased culling for non-lambing decreased productivity at flock age structure equilibrium in accelerated lambing but did not change productivity in annual lambing. Repeatability of ewe effects on conception was generally low. Overall, system, percentage Finn, and culling strategy interact to influence system productivity through flock age structure. Intensive culling for non-lambing and replacement with ewe lambs of equal genetic merit should not be practiced in accelerated lambing systems.     

Effects of Ehrlichia phagocytophila infection on serum thyroid hormone concentrations and on antipyrine clearance and metabolite formation in dwarf goats.

The influence of infection with Ehrlichia phagocytophila (EP) on serum thyroid hormone concentrations and on antipyrine (25 mg/kg of body weight, IV) plasma elimination and urinary metabolite excretion was studied in castrated male dwarf goats. Mean thyroid hormone concentrations moderately decreased in EP-infected goats, with maximal decrease in total and free triiodothyronine and thyroxine serum concentrations of 56, 64, 23, and 19%, respectively. The estimated pharmacokinetic values of antipyrine (AP) in EP-infected goats were similar to those in the goats when healthy. However, glucuronidation of the AP-metabolites 3-hydroxymethyl-AP, 4,4'-dihydroxy-AP, and 4-hydroxy-AP was reduced during the febrile episode of the acute-phase response to EP infection.     

Electron microscopy as an aid to the rapid diagnosis of virus diseases of veterinary importance

The use of electron microscopy to assist in the rapid diagnosis of virus diseases of veterinary importance is reviewed. Electron microscopy can be used to assist the laboratory diagnosis of a virus disease at two stages during the investigation; either by demonstrating virus in clinical material or by identifying isolates from tissue culture or similar systems. Direct electron microscopy and immunoelectron microscopy are particularly useful for rapid diagnosis. The advantages of electron microscopy lie in speed and flexibility, and the disadvantages in the high particle concentration needed and the presumptive nature of a diagnosis.     

Studies on neonatal calf diarrhoea caused by rotavirus: transmission of the disease and attempted vaccination of colostrum-deprived calves

Mild to severe scouring could be produced in colostrum-deprived calves with tissue culture-adapted rotavirus and feacal material from field cases of calf diarrhoea. The feaces of experimentally infected calves contained rotavirus for at least 3 days. Pathogenic bacteria were presented in one calf only and this calf also showed the most severe gastroenteritis. Eight calves were vaccinated with a live rotaviral calf diarrhoea vaccine and subsequently challenged with infective rotavirus. Mild scouring was observed after vaccination, but the calves remained normal after challenge. Rotavirus particles were detectable in the faeces for a few days after vaccination and challenge.     

Comparison of haemodynamic changes during two surgical methods for neutering female dogs

The aim was to investigate if intraoperative registrations of blood pressure and heart rate could be used to estimate surgical trauma. In a prospective clinical trial, registrations in eight dogs neutered by laparoscopic ovariectomy (LOE) were compared with eight dogs subjected to open ovariohysterectomy (OHE). For comparisons phases were used: phase zero = steady state after induction of anaesthesia; phase one = opening of abdomen; phase two = severing of ovarian pedicles; and, phase three = abdominal closure. During LOE, mean systolic blood pressure increased by 7 mm Hg (p = 0.05) and 15 mm Hg (p = 0.01) from phase zero to phase one and two, respectively, and during OHE by 3 mm Hg (ns) and 29 mm Hg (p < 0.0001), respectively. The increase from phase one to phase two differed between groups (p = 0.03). Heart rate did not change. Frequent intraoperative measurements of blood pressure appear a promising method for evaluating surgical trauma.