Objective-To determine the prevalence and temporal onset of lung lesions in lambs and the impact of lung lesions on growth of affected lambs. Animals-259 crossbred wether lambs from a single flock in the upper Midwestern United States. Procedure-An observational study was conducted. Lambs born in the spring and fall were slaughtered at finished weight or at a predetermined time point. Lungs of each lamb were examined and classified as normal, moderate lesions (consolidation > 5% but less than or equal to 50% of any lobe), or severe lesions (consolidation > 50% of any lobe). Data were examined to detect effects of prevalence or severity of lung lesions on growth and carcass traits. Results-57 of 89 (64%) spring-born lambs had lung lesions characterized by consolidation of lung tissue. A small number of lambs had pulmonary adhesions or active abscesses. In contrast, only 31 of 108 (29%) fall-born lambs had lung lesions. Severe lung lesions were associated with a significant reduction in average daily gain. Severe lung lesions were not detected until the middle of the finishing period and were associated with culture of Mannheimia haemolytica or Pasteurella multocida. Conclusions and Clinical Relevance-Analysis of results indicates that the prevalence of severe lung lesions can be quite high in lambs. Severe lung lesions can lead to greatly decreased growth performance of lambs.

Loline and ergot alkaloids found in endophyte-infected (Acremonium coenophialum) tall fescue (EITF) cause vasoconstriction of equine vessels in vitro. An aggregate risk study was used to evaluate the association between horses exposed to EITF and development of laminitis. Veterinary teaching hospitals participating in the Veterinary Medical Data Base were grouped by whether equine accessions were likely to have been at high, moderate, or low risk for exposure to EITF. From 1980-1990, there were 185,781 accessions, of which 5,536 had diagnosis of laminitis. Proportion of equine accessions with laminitis reported by veterinary teaching hospitals for high, moderate, and low risks, were 3.41, 3.04, and 2.00 cases/100 accessions, respectively (P < 0.0001). Comparison of the proportion of accessions with laminitis in the high- and moderate-risk groups with that in the low-risk group revealed significant differences between risk groups over all months (P = 0.063) and differences from month to month within risk groups (P = 0.0001). If the difference among risk groups is attributed entirely to exposure to EITF, the population-attributable risk is 7 cases/1,000 admissions, or 15% of all admissions for laminitis at veterinary teaching hospitals in our data base. Preliminary data support an association between hoses exposed to EITF and increased risk of laminitis; however, studies at the individual animal level are indicated to confirm this hypothesis.

Hypothyroidism is a possible predisposing factor in a number of disorders of companion psittacine birds. We developed and validated a thyroid-stimulating hormone (TSH) response testing protocol for cockatiels (Nymphicus hollandicus), using 0.1 IU of TSH/bird given IM, with blood sample collection at 0 and 6 hours after TSH, and a commercial radioimmunoassay for thyroxine T4). This protocol was used to document a seasonal sex difference in stimulated T4 values-females responded with higher T4 values than those in males in summer- and a stress-induced depression of baseline T4 values was detected in a group of cockatiels with normal TSH response. An experimental model for mature-onset hypothyroidism in cockatiels was created by radiothyroidectomizing cockatiels with 3.7 MBq (100 microCi) of 131I/bird given IV. Induction of the hypothyroid state was confirmed by baseline T4 concentration, TSH response test results, thyroid pertechnetate scintigraphy, and gross and microscopic examinations. Classical signs of hypothyroidism (eg, hypercholesterolemia, obesity, poor feathering) were lacking or mild at 48 days after thyroid ablation.

Association between individual cumulative milk yield and various reproductive disorders in 56,772 Finnish Ayrshire cows belonging to 5,912 herds in 80 communities was studied. All cows delivered calves between September 1985 and September 1986. Five logistic regression models were fitted, 1 for each outcome disorder of interest: early metritis, late metritis, silent heat, ovarian cyst, and other infertility. Cumulative individual 37-day milk yield was used in the early metritis model, and cumulative individual 60-day milk yield was used in the other models, on the basis of median days in milk when these disorders developed. Cumulative 305-day herd milk yield, parity, calving season, presence or absence of other disorders, and community were also included in the models. Point estimates from the models represented odds ratios for the likelihood of having the outcome disorder.Lactational incidence risks for the 5 reproductive disorders studied were: early metritis (2.4%), late metritis (1.1%), silent heat (5.4%), ovarian cyst (6.6%), and other infertility (2.1%). The risk of early metritis decreased with increasing 37-day milk yield. The risk of silent heat, ovarian cyst, and other infertility increased with increasing 60-day milk yield; 60-day milk yield had no effect on late metritis. The 305-day herd milk yield increased the risk of early metritis, ovarian cyst, and other infertility; it had no effect on late metritis or silent heat. Parity had an effect on all disorders, except late metritis. Cows that delivered calves during the colder, darker seasons of the year had a higher risk of reproductive disorders than did those that delivered calves at other times of the year. A number of other disorders, reproductive and otherwise, were significant predictors of development of the outcome disorders.

Rectal swab specimens were collected from 362 apparently healthy dogs of different origin, age, breed, and sex. Specimens were obtained in summer, autumn, and winter. Ninety-five thermophilic Campylobacter spp were isolated: C jejuni biotype I, n = 57, C jejuni biotype II, n = 1, C coli, n = 36, and C laridis, n = 1. Biotypes of C jejuni recovered were the same as those associated with Campylobacter-induced enteritis in human beings. Prevalence of C jejuni was significantly (P < 0.05) greater: in dogs < 6 months old than in adult dogs; in dogs living under high density and cohabitation housing conditions for long periods; and in autumn.

Total serum hemolytic complement (CH50) activity was determined for 3 semi-inbred strains of miniature swine (SLAa, SLAc, SLAd) and 1 recombinant strain SLAg (ABCcDd), each homozygous for a distinct major histocompability complex haplotype. Initial determination was made at 8 weeks of age, prior to standardized immunization, the second at age 12 weeks, after immunization. Analysis of variance was by least-squares method, using a linear model on data from 33 litters by 14 sires and 16 dams. Analysis of variance indicated that the combined effects of haplotype, sire, dam, litter, and gender accounted for 47.63% of the total variation in preimmunization CH50 values. Dam (P less than or equal to 0.06) and litter (P less than or equal to 0.03) significantly influenced preimmunization complement activity. Although swine leukocyte antigen (SLA) haplotype was not significant in the model, least-squares mean comparisons between haplotypes suggested that ac, dg, and gg pigs tended to have comparatively low preimmunization CH50 values. The model did not account for significant variability in postimmunization CH50 values, but least-squares means indicated that dd, dg, and gg haplotypes tended to have lower values than did other haplotypes tested. Mean CH50 units for 8-and 12-week-old pigs were 41.32 +/- 20.49 and 59.50 +/- 54.35, respectively. There was a significant difference (P less than or equal to 0.001) in CH50 activity between 8- and 12-week-old pigs associated with immunization, because CH50 of nonimmunized controls did not differ at 8 and 12 weeks.

Effects of age and season on type and occurrence of sperm abnormalities were examined in semen samples collected from 3 groups of Nubian bucks at ages of 4 to 9 months, 10 to 21 months, and 39 to 50 months. The average total percentage of sperm abnormalities at the onset of puberty (141 +/- 4 days) was 64.6 +/- 14.8% (head, 19.5 +/- 13.6%; middle piece, 17.2 +/- 9.3%; and proximal protoplasmic droplets, 14.6 +/- 10.5%), but this improved rapidly and was reduced to 12.5 +/- 7.5% by 8 months of age (head, 1.9 +/- 4.5%; middle piece, 4.6 +/- 2.8%). Further increase in age, at least up to 4 years, did not reveal a significant effect (P less than 0.05) on the type of percentage of total abnormalities. Similar to age, a comparison of data among seasons did not reveal a significant effect on the type or occurrence of sperm abnormalities in 10- to 21-month-old or 39- to 50-month-old bucks. Seemingly, Nubian bucks started producing good quality semen at 8 months of age, and season did not influence sperm abnormalities.

helminths and arthropods collected from warthogs at monthly intervals, prevalence, rainfall and temperature data, clear patterns of seasonal abundance could be determined only for Physocephalus sexalatus and Haematopinus phacochoeri

strongyles (predominantly cyathostomes), mares and their foals, dynamics of transmission studied on pastures previously free of parasites, fecal egg counts beginning day of parturition and based on time of year, relationship between weather conditions and pasture larval counts, necropsy findings in two foals: Texas