A standardized cortical defect was created on the caudal cortex of the proximal portion of each ulna in 5 adult mixed-breed dogs. One gram of autogenous cancellous bone graft (ACBG) was obtained from the greater tubercle of the ipsilateral humerus. The cortical defect in the ulna of 1 limb was filled with 1 g of ACBG that had been compressed with 2-MPa pressure for 30 seconds. One gram of noncompressed ACBG was placed into the contralateral ulnar cortical defect. The compressed and noncompressed ACBG recipient sites were radiographed at weekly intervals. Dogs were euthanatized 8 weeks after surgery, and the ACBG recipient sites were harvested for histomorphometric analysis. Optical densitometry was performed on all radiographs. There was no significant difference between compressed and noncompressed ACBG with optical densitometry or histomorphometric analysis for total bone area. We concluded that there was no difference in osteogenic capability between compressed and noncompressed ACBG of equal mass.

Body condition scoring (using a 5-point with quarter-point divisions) was performed on 66 Holstein dairy cows that began their second or later lactation in August, September, or October 1988. Cows' body condition was scored beginning on postpartum day 4 (+/- 1) and subsequently at postpartum days (+/- 1) 18, 32, 46, 60, 73 and 87. Blood samples were obtained on the same dates. Reproductive health examinations were conducted by 1 of 2 veterinarians beginning at postpartum day 21. Reproductive performance was evaluated in relation to body condition score and serum urea nitrogen and cholesterol concentrations. Number of days to first recorded signs of estrus and first breeding were not related to body condition score at calving, amount of condition loss, cumulative 80-day milk yield, or 305-day fat corrected milk yield. Cows that calved with body condition score greater than or equal to 3.50 required more days to conceive. Cows losing > 0.75 points of condition had longer days of conception. Body condition score at calving and amount of condition lost were not related to services per conception or diagnosis of follicular cyst. Cumulative 80-day milk yield was not related to days to conception or services per conception. Cows that produced greater than or equal to the mean 305-day milk yield required more services and had longer days to conception than cows that produced < the mean 305-day milk yield. Cows with diagnosis of ovarian follicular cysts had greater cumulative 80- and 305-day milk yields than did cows that were not diagnosed with follicular cysts. Cows conceiving with less than or equal to 2 services did not differ in average daily milk production, body condition score, or serum urea nitrogen concentration from cows conceiving with > 2 services, but cows that conceived with less than or equal to 2 services had higher serum cholesterol values than did cows requiring more services.

Liquid mercury strain gauges were implanted in the forelimb proximal sesamoidean ligaments (PSL) of 8 adult horses. The gauges measured PSL strain while horses were standing with or without external support. In 6 of the horses, the gauges also measured PSL strain in horses at a walk, with or without external support. Gauges were enclosed within sliding polypropylene tubes to prevent nonaxial deformation. Each gauge was placed in 1 arm of a low-resistance half-bridge circuit. To provide temperature compensation, a dummy gauge was placed in the adjacent arm of the bridge circuit and was implanted next to the active gauge in the surrounding fascial tissue. External support included fiberglass cast support (CAST), dorsal fetlock splint support (DFS), support wraps of 3 bandage materials (SW1, SW2, and SW3), and support wrap with caudal splint (SW4). The cast was applied, with the fetlock and foot in weightbearing position, from the proximal portion of the metacarpus distal to and including the foot. The DFS was applied by placing the cranial half of the fiberglass cast on the dorsal aspect of the instrumented limb. The SW1, SW2, and SW3 were applied in a figure-8 pattern around the fetlock, using 50% of the linear stretch capacity of the bandage material, with the horse standing squarely on all 4 limbs. The SW4 was applied identically to the other support wraps, with the exception of addition of a flexible caudal splint incorporated in the support wrap. Mean maximal strain while standing without external support for 8 horses was 6.0% (range, 3.8 to 7.5%). Mean maximal strain at a walk without external support for 6 horses was 5.9% (range, 4.1 to 8.2%). Only cast and DFS significantly reduced mean maximal strain while standing. Cast support reduced mean maximal strain while standing to a mean +/- SEM 1.4 +/- 0.2%, 77% reduction in total strain (P < 0.0001). Use of DFS reduced mean maximal strain while standing to a mean 4.2 +/- 0.3%, 30% reduction in total strain (P < 0.0001). The SW1, SW2, and SW3 did not significantly reduce mean maximal strain while standing (power > 0.8, delta = 20%). Conclusions cannot be made for reduction of mean maximal strain while standing with SW4 (power < 0.8, delta = 20%) because of low sample size. Only CAST and DFS significantly reduced mean maximal strain while walking. Cast support reduced mean maximal strain while walking to a mean 2.0 +/- 0.3%, 67% reduction in total strain (P < 0.0001). The DFS reduced mean maximal strain while walking to a mean 4.4 +/- 0.4%, 25% reduction in total strain (P < 0.008). The SW1, SW2, and SW3 did not significantly reduce mean maximal strain while walking (power > 0.8, delta = 20%). Conclusions cannot be made for reduction of mean maximal strain while walking with SW4 (power < 0.8, delta = 20%) because of low sample size.

The effects of 2 liquid formula diets differing in protein source were evaluated in orphan foals. The response of 7 foals fed a diet containing casein as the protein source, and 6 foals fed a diet containing a combination of whey and casein, was compared with the response in a reference group of 8 mare-raised foals. Orphaned foals were fed 150 kcal/kg of body weight/d, divided into 6 equal feedings of 25 kcal/kg. Formula intake was comparable among the experimental groups, and foals fed the liquid formula diet grew as well as mare-raised foals. There was no difference among groups in mean daily body weight gain, wither height, heart girth, body temperature, pulse, respiration rate, capillary refill time, or skin tenting. Insulin and blood glucose concentrations increased in both groups of foals fed formula diets, returning to prefeeding values within 4 hours. Differences among groups were found for serum alkaline phosphatase, alanine transaminase, cholesterol, creatinine, and glucose values; all other serum chemical values were comparable among groups. Plasma amino acid determinations revealed that arginine and ornithine were significantly lower in foals in both experimental groups than in reference foals, suggesting that arginine may have been the limiting amino acid in these diets. Diarrhea developed in foals in all treatment groups, but in most cases was self-limiting. These results suggest that the protein source of liquid formula diets may be less important in foals than in infants.

Twenty-nine pruritic, atopic dogs were entered into a double-blind, placebo-controlled, crossover study to evaluate the efficacy of an investigational antiallergenic compound, AHR-13268. Fourteen dogs were evaluated by a veterinary dermatologist (at intervals) and the owner (daily). Fifteen dogs were evaluated only by the owner. The mean (+/- SE) owner scores for pruritus, erythema, and lesions with placebo treatment (higher score = worse signs) were 3.24 (+/- 0.12), 2.73 (+/- 0.12), and 2.61 (+/- 0.09), respectively. With drug treatment, the corresponding scores were 2.89 (+/- 0.12), 2.50 (+/- 0.12), and 2.25 (+/- 0.09). Scores for pruritus and lesions (but not erythema) were significantly better with drug treatment than with placebo treatment. Investigator scores showed similar trends, but the differences were not great enough to be statistically significant. Overall, 11/29 (38%) owners reported their dogs had moderate or better improvement from drug capsules, and 4/29 dogs (14%) improved on placebo capsules. A variety of adverse effects were reported following both drug (9/29 dogs) and placebo (8/29 dogs) capsule administration, but were mild and well tolerated. Results of this study indicate that AHR-13268 has potential for empiric treatment of allergic inhalant dermatitis in some dogs.

Several pharmaceutical compounds were evaluated for their ability to selectively inhibit activated coagulation factor-XIII-like enzyme activity (eg, XIIIa) in pooled equine plasma. Presence of coagulation factor-XIIIa -like enzyme activity in plasma was established by assay procedures involving incorporation of the fluorescent amine compound, monodansylcadaverine, into purified casein, which served as a protein substrate. Pharmaceuticals inhibitory to coagulation factor-XIIIa -like enzyme activity were recognized by plasma gel formation of high spectrophotometric transmittance (transparency), solubility of transparent fibrin gels in concentrated urea solution, in conjunction with simultaneous depletion of native fibrinogen fractions, and production of fibrin monomer. Compounds acting primarily as anticoagulants were recognized by lack of plasma gel formation, but retaining high spectrophotometric transmittance and no detectable depletion of native fibrinogen fractions. Compounds failing to inhibit either thrombin-mediated fibrinogen-fibrin transformation (ie, coagulation) or coagulation factor-XIIIa -like enzyme activity were recognized by opaque plasma gels caused by fibrin polymerization, low spectrophotometric transmittance values, and coinciding with depletion of native fibrinogen fractions. Pharmaceuticals capable of exerting selective inhibition of coagulation factor-XIIIa -like enzyme activity were further classified as competitive inhibitors of phase 1 (carbamide) or phase 2 (terminal amine) of the transglutamination process.

Beagles were exposed to aerosols of (239)PuO2, (238)PuO2, or (239)Pu(NO3)4. Exponential growth constants for 50 primary lung tumors (23 bronchioloalveolar carcinomas, 22 papillary adenocarcinomas, 5 adenosquamous carcinomas) were calculated in 37 dogs, using sequential thoracic radiography. A wide range in doubling time (6 to 287 days) was observed. Mean +/- SEM doubling time was 93 +/- 10 days for bronchioloalveolar carcinoma, 107 +/- 13 days for papillary adenocarcinoma, and 101 +/- 36 days for adenosquamous carcinoma. Lung tumor growth rate in dogs was comparable to that in human patients with similar histologic tumor types. Linear regression analysis revealed significant (P less than or equal to 0.0001) correlation between doubling time and survival of individual dogs. Doubling time was not significantly dependent on tumor type, sex, age at time of diagnosis, initial lung deposition, or isotope. Extrapolating time to tumor onset from tumor doubling time cannot be used to reliably predict the onset of malignancy.

We examined the efficacy of ivermectin in the control of ear mites (Psoroptes cuniculi) in rabbits. The study involved 40 female and 35 male rabbits that were known to be naturally infested with ear mites. After a period of acclimation to the animal care facilities, the rabbits were ranked on the visual appearance of any ear lesion and the number of mites on glycerin-dipped ear swabs. The rabbits were then randomly assigned to 1 of 4 treatment groups; vehicle only (group 1), 50 micrograms of ivermectin/kg of body weight (group 2), 100 micrograms of ivermectin/kg (group 3) and 200 micrograms of ivermectin/kg (group 4). The rabbits were treated by SC injections on day 0 and day 14 of the trial; thus, the total dose of ivermectin given to groups 1 through 4, was 0, 100, 200, or 400 micrograms/kg, respectively. The study ended 2 weeks after the last treatment. Ear lesions of the treated rabbits improved significantly (P < 0.001). By 28 days after the first treatment, the mean number of mites on the ear swabs (both ears) was 57.5 for untreated rabbits and 9.1, 0.5, and 2.5, respectively, for rabbits in groups 2, 3, and 4. The mean number of mites recovered from the ears of the untreated rabbits at necropsy was 24,297. For groups 2, 3, and 4, the mean number of mites recovered from the ears was 5,352, 96, and 96, respectively. The efficacy of treatment with a total dose of 100 micrograms/kg was 77.96%, with 200 micrograms/kg was 99.61%, and for 400 micrograms/kg was 99.61%.

The scavenging of superoxide radicals by endogenous and therapeutically administered superoxide dismutases may prevent superoxide-mediated oxidative stress leading to lipid peroxidation, membrane lysis, and cell death in a wide variety of normal and pathologic states. Simple inorganic manganous salts such as MnCl2 also have superoxide dismutase-like activity and are extremely inexpensive, compared with enzymatic superoxide dismutase preparations. In this study, we explored the use of Mn salts as antioxidant drugs. We used the percentage of inhibition of nitroblue tetrazolium reduction by superoxide as a measure of the amount of superoxide dismutase-like activity. We found concentration-related increases in superoxide scavenging activity in simple buffer solutions upon addition of 1.25, 2.5, and 5.0 microM MnSO4. To determine whether Mn salts can inhibit oxidative damage in tissues, we used an in vitro model of lipid peroxidation in ischemic and reoxygenated rat liver slices. Concentrations of 10, 100, and 1000 micromoles MnCl2/L of buffer significantly decreased indicators of lipid peroxidation believed to be initiated by intracellular superoxide. We then determined the effectiveness of MnCl2 as a superoxide scavenger in conscious horses by measuring the superoxide scavenging ability of equine plasma before and during intravenous infusions of 1.0 L volumes of 0.9% saline solution containing 0, 12.5, or 25 mM MnCl2. Plasma Mn concentrations, which were determined by atomic absorption spectrophotometry, increased as a function of time and dose. Intravenously administered MnCl2 concomitantly produced dose-related increases in superoxide scavenging ability of equine plasma at 15, 30, 45, and 60 minutes after the onset of infusion, compared with preinfusion control values. Heart rate and blood pressure of the treated horses, which were monitored to measure toxicity of MnCl2, gradually increased in both treatment groups. Clinical adverse effects of MnCl2 administration included defecation, pawing, hyperexcitability, flank watching, and sweating. The results of this study indicate that simple Mn salts may scavenge superoxide radicals in vivo with minimal adverse reactions and at a trivial cost.

The nuclear imaging technique known as quantitative renal scintigraphy was validated as a means to assess the kidney function of cats. Renal function tests were performed in 6 healthy cats and 3 cats with clinical manifestations of kidney failure. In addition, the nephrotoxic drugs, gentamicin sulfate, or amphotericin B were used in an attempt to induce renal failure in 4 cats. Using linear regression analysis, equations were derived to estimate the glomerular filtration rate (GFR) on the basis of the renal percent uptake of 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA). One-way ANOVA and Student's t test were used to evaluate treatment effects on clearances of inulin and creatinine, percent uptake of 99-Tc-DTPA, and serum creatinine concentrations. The results show that the percent uptake of 99mTc-DTPA by the kidneys correlated well with the GFR obtained through the clearance of inulin. Thus, it was concluded that quantitative renal scintigraphy, using 99mTc-DTPA as a marker of kidney function, is an adequate technique to estimate the kidney function of healthy cats and cats with functional renal impairment. The best estimate of the GFR of cats, using the percentage dose of 99mTc-DTPA, was obtained on the 1- to 3-minute postinjection interval of the marker, using data that was background-subtracted, but not corrected for tissue absorption of gamma rays or binding of 99mTc-DTPA to plasma proteins. There was no significant difference in the mean inulin clearance, creatinine clearance, or percent uptake of 99mTc-DTPA between the 3 treatment groups of this study. Therefore, it was concluded that neither gentamicin nor amphotericin B are useful drugs in eliciting losses of feline kidney function that may be measurable through the procedures used in this study. Contrary to all other GFR studies in the cat, this study did not use any form of pharmacologic restraint. Therefore, the findings from this study are expected to reflect accurately the true GFR healthy nonanesthetized cats.