Early prenatal androgenization results in diminished ovarian reserve in adult female rhesus monkeys

BACKGROUND

Early prenatal androgenization (PA) accelerates follicle differentiation and impairs embryogenesis in adult female rhesus monkeys (Macaca mulatta) undergoing FSH therapy for IVF. To determine whether androgen excess in utero affects follicle development over time, this study examines whether PA exposure, beginning at gestational days 40-44 (early treated) or 100-115 (late treated), alters the decline in serum anti-Mullerian hormone (AMH) levels with age in adult female rhesus monkeys and perturbs their ovarian response to recombinant human FSH (rhFSH) therapy for IVF.

METHODS

Thirteen normal (control), 11 early-treated and 6 late-treated PA adult female monkeys had serum AMH levels measured at random times of the menstrual cycle or anovulatory period. Using some of the same animals, basal serum AMH, gonadotrophins and steroids were also measured in six normal, five early-treated and three late-treated PA female monkeys undergoing FSH therapy for IVF during late-reproductive life (>17 years); serum AMH also was measured on day of HCG administration and at oocyte retrieval.

RESULTS

Serum AMH levels in early-treated PA females declined with age to levels that were significantly lower than those of normal (P < or = 0.05) and late-treated PA females (P < or = 0.025) by late-reproductive life. Serum AMH levels positively predicted numbers of total/mature oocytes retrieved, with early-treated PA females having the lowest serum AMH levels, fewest oocytes retrieved and lowest percentage of females with fertilized oocytes that cleaved.

CONCLUSIONS

Based on these animals, early PA appears to program an exaggerated decline in ovarian reserve with age, suggesting that epigenetically induced hormonal factors during fetal development may influence the cohort size of ovarian follicles after birth.

Alpha-synuclein, pesticides, and Parkinson disease: a case-control study

BACKGROUND

Aggregation and fibrillization of the alpha-synuclein protein (encoded by the SNCA gene) may represent key events in the pathogenesis of Parkinson disease (PD). Variability in the length of a dinucleotide repeat sequence (REP1) within the SNCA promoter confers susceptibility to sporadic PD. Pesticide exposures may also confer susceptibility to PD. Our objective was to test possible joint effects of SNCA REP1 genotypes and pesticide exposures on the risk of PD.

METHODS

This was a case-control study. Cases were recruited prospectively from the Department of Neurology of the Mayo Clinic, Rochester, MN, after June 1, 1996. The control subjects included unaffected siblings of cases and unrelated population control subjects. We assessed pesticide exposures by telephone interview and genotyped SNCA REP1. Odds ratios (ORs) and 95% CIs were determined using conditional logistic regression models.

RESULTS

There were 833 case-control pairs. We observed an increased risk of PD with increasing SNCA REP1 bp length (OR, 1.18 for each score unit; 95% CI, 1.02-1.37; p = 0.03). Pesticide exposures were associated with PD in younger subjects only (lowest quartile of age at study, <or=59.8 years; OR, 1.80; 95% CI, 1.12-2.87; p = 0.01 for all pesticides; OR, 2.46; 95% CI, 1.34-4.52; p = 0.004 for herbicides). In multivariate analyses, both SNCA REP1 score and pesticide exposures were significantly associated with PD in younger subjects, but there were no pairwise interactions.

CONCLUSIONS

Our findings suggest that SNCA REP1 genotype and herbicides have independent effects on risk of Parkinson disease, primarily in younger subjects.

A limited role for DJ1 in Parkinson disease susceptibility

An association study of four common polymorphisms in the DJ1 gene and Parkinson disease (PD) was conducted. PD probands were compared with their unaffected siblings matched by gender and closest age at study (416 vs 416) and with unrelated control subjects (691 vs 190). None of the four haplotype tagging single-nucleotide polymorphisms (SNPs) was associated with PD overall, but SNP1 (position 4,345 bp) and SNP3 (position 16,491 bp) were associated with PD in women (p = 0.03 and p = 0.002).

Expression of estrogen receptor isoforms alpha and beta messenger RNA in vaginal tissue of premenopausal and postmenopausal women

OBJECTIVE

To determine the messenger RNA expression patterns of estrogen receptor (ER)alpha and ER beta in human vaginal tissue.

STUDY DESIGN

Reverse transcriptase-polymerase chain reaction was performed on tissue samples of 75 patients having anterior colporrhaphy (25 premenopausal, 25 postmenopausal receiving estrogen replacement therapy [ERT], 25 postmenopausal not receiving ERT). Levels of mRNA were normalized and ratios were calculated to assess relative levels of expression.

RESULTS

All samples showed expression of the ER alpha isoform. Significant differences existed in ER alpha expression among the 3 cohorts (P =.023). Greater differences (P <.001) existed in ER beta expression. For both isoforms, the premenopausal group had the highest level, and the postmenopausal group receiving ERT had the lowest level. No significant difference in ER beta expression existed between postmenopausal groups.

CONCLUSION

Significant differences exist between premenopausal and postmenopausal women in presence and expression of ER alpha and ER beta in vaginal tissue. Expression of ER beta markedly declines in menopause, regardless of ERT use.

Endometrial markers of uterine receptivity utilizing the donor oocyte model

BACKGROUND

Ethical constraints limit the ability to study peri-implantation phase human endometrium. In this study, the donor oocyte model was used to study candidate endometrial markers of uterine receptivity.

METHODS

Archived, paraffin-embedded tissue obtained by endometrial biopsy during cycle days 21-23 of patients undergoing 'mock' hormonal treatment cycles were evaluated by standard histological criteria and immunohistochemical staining for alpha v beta 3 integrin and glycodelin. All of these patients (n = 101) had undergone a donor oocyte embryo transfer cycle utilizing the exact same hormonal protocol.

RESULTS

Histological evaluation revealed 62 (61.3%) in-phase, 34 (33.7%) dyssynchronous, 2 (2.0%) immature and 3 (3.0%) advanced endometria. The clinical outcomes of patients with either in-phase or dyssynchronous endometria were similar. Very strong correlations were noted between endometrial glandular dating and either alpha v beta 3 integrin or glycodelin immunostaining intensity (P < 0.001 for both). Glycodelin and alpha v beta 3 integrin immunostaining intensities were also highly correlated with each other (P < 0.001).

CONCLUSIONS

Throughout the time period corresponding to the putative window of maximal endometrial receptivity (cycle days 21-23) a dynamic process was observed in exogenous hormonal replacement cycles characterized by a rapid histological advancement of endometrial glandular elements as well as progressive alpha v beta 3 integrin and glycodelin expression.

alpha-Synuclein gene haplotypes are associated with Parkinson's disease

We report haplotype analysis of the alpha-synuclein gene in Parkinson's disease (PD), extending earlier reports of an association with a polymorphism within the gene promoter. This analysis showed significant differences in haplotypes between PD cases and controls. Our analyses demonstrate that genetic variability in the alpha-synuclein gene is a risk factor for the development of PD. These genetic findings are analogous to the tau haplotype over-represented in progressive supranuclear palsy and further extend the similarity in the etiologies and pathogeneses of the synucleinopathies and tauopathies.

Ovarian morphology and serum hormone markers as predictors of ovarian follicle recruitment by gonadotropins for in vitro fertilization

Twenty-five normal ovulatory women underwent three-dimensional transvaginal ultrasonography and blood sampling before and after oral glucose tolerance testing to compare ovarian morphology and circulating hormone levels in the early follicular phase as predictors of the number of oocytes retrieved after gonadotropin stimulation for in vitro fertilization. Serum levels of gonadotropins, inhibins, testosterone, dehydroepiandrosterone sulfate, and estradiol as well as summed ovarian volume were unrelated to oocyte number. Antral follicle number and serum androstenedione level, however, positively correlated, whereas postoral glucose tolerance test (post-OGTT) insulin release negatively correlated, with total and mature oocyte numbers. Adjusting for age and body mass index by regression analysis, the serum androstenedione level significantly predicted mature, but not total, oocyte number. The relationships of antral follicle number and post-OGTT insulin release to total oocyte number were additive; each was significant after controlling for the other. In contrast, antral follicle number significantly correlated with mature oocyte number after controlling for post-OGTT insulin release, whereas post-OGTT insulin release was unrelated to mature oocyte number after controlling for antral follicle number. Therefore, early follicular phase antral follicle number positively correlates with total and mature oocyte numbers after gonadotropin stimulation for in vitro fertilization and is linked to androgen and insulin actions in predicting ovarian follicle recruitment by gonadotropins.

Significance of pathologic patterns of pelvic lymph node metastases in endometrial cancer

OBJECTIVE

The aim of this study was to correlate the pathologic characteristics of pelvic lymph node metastases with survival, recurrence, and patterns of recurrence in endometrial cancer.

METHODS

Sixty patients with epithelial endometrial cancer and pelvic node metastasis were managed surgically between 1984 and 1993 at the Mayo Clinic. The mean number of nodes harvested was 16.7 and the mean number of nodes positive was 3.0. Mean follow-up was 45.5 months. The pathologic patterns of lymph node metastases were characterized.

RESULTS

Outcome was related to pathologic patterns of pelvic node metastasis. Both diameter of lymph node metastasis (P < 0.01) and capsular integrity (P < or = 0.01) influenced 5-year disease-related survival and 5-year progression-free survival. The percentage of biopsied pelvic lymph nodes harboring metastatic disease and the proportion of the involved lymph nodes occupied by tumor significantly influenced death rates and recurrence rates (P < 0.05). The immune response and the absolute number of positive pelvic nodes did not impact recurrence or survival. The above characteristics of pelvic node metastasis correlated also with patterns of recurrence. Regression analysis indicated that capsular integrity (RR = 2.97; P = 0.005) and proportion of positive pelvic nodes biopsied (RR = 3.84; P = 0.01) were significant predictors of recurrence, whereas diameter of metastasis (RR = 3.68; P = 0.02) and proportion of positive pelvic nodes biopsied (RR = 4.04; P = 0.02) were most predictive of survival.

CONCLUSIONS

The pathologic patterns of pelvic node metastasis appear to be significantly related to survival, recurrence, and patterns of recurrence.

Gastrointestinal surgery in patients with ovarian cancer

OBJECTIVES

The objectives were to assess indications for and outcome and morbidity of gastrointestinal surgery in patients with ovarian cancer.

METHODS

We reviewed 364 patients with ovarian cancer who underwent a total of 491 operations including a gastrointestinal procedure over a 10-year period. The 491 operations comprised 180 primary surgical procedures (37%), 44 second-look laparotomies (9%), and 267 procedures for recurrence or palliation (54%).

RESULTS

Debulking of disease was the indication for bowel surgery for 87, 45, and 62% of cases in the three groups, respectively. Bowel obstruction was an indication in 14% of patients at primary surgery and in 34% at secondary surgery (P < 0.05). Rectosigmoid resection was the most common bowel operation overall, particularly in the primary surgery group (65%). Colostomy was performed in 30% of the cases of rectosigmoid resection at primary surgery. Small-bowel resection was most common in the surgery for recurrence or palliation group. The blood transfusion rate was 79%. Febrile morbidity was the most common complication overall (29%), with no significant differences among groups. Four patients (0.8%) required reoperation for an abscess or anastomotic leak. Nineteen operations (3.9%) were followed by death within 30 days, with no significant differences among groups. A weighted Cox model estimated that 21, 42, and 11% of patients would be alive 5 years after primary surgery, second-look laparotomy, and surgery for recurrence or palliation, respectively (P = 0.01).

CONCLUSION

Gastrointestinal surgery is frequently indicated during operations for ovarian cancer. Gynecologic cancer surgeons should be trained accordingly. Patients with possibly malignant ovarian masses should receive preoperative bowel preparation and be counseled that bowel surgery may be needed but colostomy is not frequently required.

Higher risk of mismatch repair-deficient colorectal cancer in alpha(1)-antitrypsin deficiency carriers and cigarette smokers

Microsatellite instability (MSI) is a genomic alteration observed in 15-30% of colorectal cancer (CRC). Two MSI phenotypes have been defined for CRC: MSI-H is characterized by MSI at > or =30% of the examined loci and MSI-L by MSI at 1-30% of the loci. An absence of MSI at any examined loci has been defined as a microsatellite stable (MSS) phenotype. Current data suggest the majority of MSI tumors are the result of defective DNA mismatch repair (MMR). In this study, we have determined the alpha(1)-antitrypsin deficiency carrier (alpha(1)ATD-ht) status of 161 CRC patients whose MSI phenotype and protein expression states had previously been determined. Cases were selected to enrich a larger number of MSI-H cases. Among 51 CRC patients with MSI-H tumors, the alpha(1)ATD-ht rate was 21.6%; among 110 patients with MSI-L/MSS tumors, the rate was 9.1% (MSI-H vs MSI-L/MSS, P = 0.02); and among the 191 population-based controls the alpha(1)ATD-ht rate was 9.4% (MSI-H vs controls, P = 0.02). The estimated relative risk of having MSI-H CRC among alpha(1)ATD-ht was 3.1 after adjusting for age, gender, and smoking history. The risk of having MSI-H CRC among current and past smokers was 6.6 and 2.7, respectively. Patients who were alpha(1)ATD-ht and smoked had a 20-fold increased risk of developing an MSI-H CRC compared to nonsmokers who were homozygous normal at the alpha(1)ATD locus. Our findings suggest an etiologic link between alpha(1)ATD alleles and development of CRC with defective MMR, and a synergistic effect between smoking and alpha(1)ATD allele in the development of MSI-H CRC.

Pretreatment assessment of prognostic indicators in endometrial cancer

OBJECTIVE

The object of this study was to assess the association of histologic, cytokinetic, and molecular variables in preoperative endometrial samples with extrauterine disease, recurrence, and survival among patients with endometrial cancer.

STUDY DESIGN

In a case-cohort study of 125 women, ploidy, S-phase fraction, proliferative index, deoxyribonucleic acid index, proliferating cell nuclear antigen, MIB-1 proliferation marker, p53 tumor suppressor gene, and cytoplasmic HER-2/neu oncogene and bcl-2 expressions were quantitated.

RESULTS

A model with only one independent term predicted progression-free survival; that variable was p53 (P <. 0001; relative risk, 5.60). A model with two independent terms predicted disease-related survival; these variables were p53 (P =. 0002; relative risk, 7.39) and MIB-1 (P =.03; relative risk, 3.27). Among patients with tumors with both p53 and MIB-1 expression exceeding 33%, a total of 32% had died of disease by 2 years. A model for predicting extrauterine disease selected two independent variables: p53 (odds ratio, 3.20; P =.01) and ploidy (odds ratio, 2. 16; P =.04). An advanced surgical stage was encountered in 26% to 35% of cases in which either the p53 expression exceeded 33% or the deoxyribonucleic acid content was nondiploid and in 53% of cases in which both variables were unfavorable.

CONCLUSIONS

Preoperative evaluation of quantifiable cytokinetic and molecular variables can assist in identifying tumor types that are predisposed toward a more aggressive clinical course.

Assessment of inhibin and p53 in granulosa cell tumors of the ovary

OBJECTIVE

The goal of this work was to determine the cellular content of inhibin and p53 in granulosa cell tumors (GCTs).

METHODS

Clinical records of 47 patients (mean age, 54 years; range, 20-85 years) presenting with GCT surgically managed at our institution were abstracted. International Federation of Gynecology stage I was assigned in 39 patients, stage II in 2, and stage III in 6. Concomitant endometrial carcinoma was identified in 6 patients. Mean follow-up was 13.6 years (range, 1 day to 37.6 years). Sections from paraffin-embedded tissue blocks were analyzed immunohistochemically for expression of tissue inhibin and p53 levels. Inhibin expression was graded by intensity and reactivity, and p53, by its presence or absence.

RESULTS

The tumors of 27 patients (57%) stained strongly for inhibin intensity and showed >60% reactivity. Decreased intensity and reactivity of inhibin expression were associated with advanced-stage disease (P = 0.05 and P < 0.01, respectively, by Fisher exact test). Expression of p53 was detected in tumors from 27 patients (57%), and immunoreactivity was associated with compromised progression-free survival (P = 0.016, log-rank test). However, the association between p53 immunoreactivity and disease stage was not significant. Absence of p53 expression was significantly associated with concurrent endometrial carcinoma (P = 0.022), suggesting more molecularly intact tumors that retain functional activity.

CONCLUSIONS

Although the majority of GCTs show strong expression of inhibin with regard to intensity and reactivity, weak expression is associated with advanced disease but not with decreased progression-free survival. By contrast, expression of p53 is not significantly associated with stage, but increased expression is associated with decreased disease-free survival. Absence of p53 expression appears to be associated with concurrent endometrial carcinoma.

Pediatric parotid masses

OBJECTIVE

To evaluate the incidence, types, and treatment outcomes of pediatric parotid lesions.

DESIGN

Retrospective case review, histological tissue review, and literature review.

SETTING

Tertiary care center.

PATIENTS

All patients aged 18 years and younger with parotid masses evaluated and treated at the Mayo Clinic, Rochester, Minn, from January 1, 1970, to December 31, 1997.

RESULTS

Parotid masses were identified in 118 children (60 boys and 58 girls). At diagnosis, the ages of patients were from birth through 18 years, and 72 (61.0%) were aged 10 years and older. An asymptomatic mass was the most common presentation. Forty-three patients (36.4%) had infectious or inflammatory lesions, 56 (47.5%) had benign lesions, and 19 (16.1%) had malignant lesions. The most common benign lesions were pleomorphic adenoma (22.9%) and hemangioma (10.2%). The most common malignant lesions were mucoepidermoid carcinoma (6.8%) and acinic cell carcinoma (3.4%). The most common treatment was total parotidectomy (40.7%). Surgical complications included temporary facial nerve weakness in 22 (18.6%) patients, permanent facial weakness in 11 (9.3%), and permanent paralysis in 2 (1.7%). Pleomorphic adenoma recurred in 4 (14.8%) of 28 patients and mucoepidermoid carcinoma in 3 (37.5%) of 8 patients. One patient with adenoid cystic carcinoma died of the tumor.

CONCLUSIONS

Although pediatric parotid masses are unusual, they can represent a variety of pathological diagnoses, including malignancy. We advocate prompt evaluation and treatment of these masses, and suggest guidelines for their management, based on diagnosis.

Alpha1-antitrypsin deficiency allele carriers among lung cancer patients

Lung cancer (LC) and chronic obstructive pulmonary lung diseases (COPDs; including emphysema and chronic bronchitis) share a common etiology. Despite the known associations of alpha1-antitrypsin deficiency (alpha1AD) with COPD and COPD with LC, few studies examined the association of alpha1AD alleles and LC. We hypothesize that heterozygous individuals who carry a deficient allele of the alpha1AD gene Pi (protease inhibitor locus) are at an increased risk of developing LC. The Pi locus is highly polymorphic with >70 variants reported. There are at least 10 alleles associated with deficiency in alpha1-antitrypsin. Using an exact binomial test, we compared the alpha1AD carrier rate in 260 newly diagnosed Mayo Clinic LC patients to the reported carrier rate in Caucasians in the United States (7%). alpha1AD carrier status, determined by isoelectric focusing assay, was examined with respect to the history of cigarette smoking, COPD, and histological types. Thirty-two of the 260 patients (12.3%; 95% confidence interval, 8.6-16.9%) carried an alpha1AD allele, which was significantly higher than expected (P = 0.002). Twenty-four of the 32 carriers had allele S, 6 had allele Z, and 2 had allele I. Patients who never smoked cigarettes were three times more likely to carry a deficient allele (20.6%; P = 0.008), although smokers had a higher carrier rate (11.1%; P = 0.025) when compared with the 7% rate. Patients with squamous cell or bronchoalveolar carcinoma had a significantly higher carrier rate than expected (15.9% and 23.8%, P < or = 0.01, respectively). Our preliminary findings suggest that individuals who carry an alpha1AD allele may have an increased risk for developing LC, specifically squamous cell or bronchoalveolar carcinoma.

Association of low CYP3A activity with p53 mutation and CYP2D6 activity with Rb mutation in human bladder cancer

p53 and Rb gene mutations are intermediate biomarkers useful for the prediction of neoplastic progression in bladder cancers. Previously, we have shown that low CYP3A activity, measured by dapsone N-hydroxylation, and high CYP2D6 activity, assessed by debrisoquine 4-hydroxylation, were significant susceptibility risk factors in developing aggressive bladder cancer. However, no information is available about the relationship between drug/xenobiotic metabolizing enzyme activities and p53/Rb mutations that may suggest mechanisms of bladder carcinogenesis. We evaluated in vivo CYP3A activity by the dapsone recovery ratio (DPRR), CYP2D6 activity by the debrisoquine recovery ratio (DBRR), CYP2C19 activity by the mephenytoin R/S ratio (RSR), N-acetyltransferase activity by the monoacetyl dapsone to dapsone ratio and glutathione-S-transferase M1 (GSTM1) genotype by PCR. In immunohistochemical studies of bladder tumor tissue, over expression of p53 protein was detected with antibody pAb1801 and loss of Rb protein expression was evaluated with antibody PMG3-245 in patients with transitional cell carcinoma of the bladder. Low CYP3A activity was significantly associated with over expression of or mutated p53 protein (P < 0.05). High CYP2D6 activity (within the extensive metabolizer group) was significantly associated with loss of expression of or mutated Rb protein (P < 0.05). Positive p53 staining also predicted aggressive bladder cancer histopathology (P < 0.05, odds ratio 2.9), and the lowest tertile of DPRR predicted p53 positivity (P < 0.01, odds ratio 3.9 comparing means of lower tertile versus upper tertile of DPRR). These selective associations are consistent with the hypothesis that an environmental pro-carcinogen fails to be detoxified by CYP3A which may preferentially induce p53 mutations, whereas, an alternative pro-carcinogen that may be activated by CYP2D6, may selectively induce Rb mutations.

The procarcinogen hypothesis for bladder cancer: activities of individual drug metabolizing enzymes as risk factors

Bladder cancer provides the most definitive example for an association between environmental agents and cancer. However, in the absence of industrial occupational exposure, the primary carcinogen is rarely identified, and the mechanisms involved in cancer formation are poorly understood. The environmental procarcinogen hypothesis of tumour pathogenesis proposes that many carcinogens require metabolic activation by drug metabolizing enzymes to form the proximate carcinogen. A balance of exposure to the carcinogen, the activity of the enzymes involved in either formation of proximate carcinogen, or production of non-toxic metabolites, will determine tumour risk. We have used mephenytoin, debrisoquine and dapsone as selective probes for the phenotypic measures of activity of CYP2C19, CYP2D6, and CYP3A4, respectively. Within subject reproducibility of phenotypic measures, and the lack of cross-inhibition when the three drugs are given in a concurrent cocktail, have been confirmed. We have applied the cocktail drug approach in two, non-overlapping series of cases with bladder cancer and matched controls. In both series, patients with aggressive bladder cancer (GIII histopathology) had a history of excess alcohol intake, an under-representation of poor metabolizers of debrisoquine, a significant mean reduction in dapsone recovery ratio, but no difference in mephenytoin phenotype. Collectively, these observations involving multiple routes of drug metabolism support the procarcinogen environmental hypothesis for bladder cancer and suggest that measurement of activity of selected individual drug metabolizing enzymes involved in the pathogenesis of this tumour can be used to identify subjects at high risk of developing bladder cancer.

Diabetes and pregnancy. Factors associated with seeking pre-conception care

OBJECTIVE

To define sociodemographic characteristics, medical factors, knowledge, attitudes, and health-related behaviors that distinguish women with established diabetes who seek pre-conception care from those who seek care only after conception.

RESEARCH DESIGN AND METHODS

A multicenter, case-control study of women with established diabetes making their first pre-conception visit (n = 57) or first prenatal visit without having received pre-conception care (n = 97).

RESULTS

Pre-conception subjects were significantly more likely to be married (93 vs. 51%), living with their partners (93 vs. 60%), and employed (78 vs. 41%); to have higher levels of education (73% beyond high school vs. 41%) and income (86% > $20,000 vs. 60%); and to have insulin-dependent diabetes mellitus (IDDM) (93 vs. 81%). Pre-conception subjects with IDDM were more likely to have discussed pre-conception care with their health care providers (98 vs. 51%) and to have been encouraged to get it (77 vs. 43%). In the prenatal group, only 24% of pregnancies were planned. Pre-conception patients were more knowledgeable about diabetes, perceived greater benefits of pre-conception care, and received more instrumental support.

CONCLUSIONS

Only about one-third of women with established diabetes receive pre-conception care. Interventions must address prevention of unintended pregnancy. Providers must regard every visit with a diabetic woman as a pre-conception visit. Contraception must be explicitly discussed, and pregnancies should be planned. In counseling, the benefits of pre-conception care should be stressed and the support of families and friends should be elicited.

Factors associated with average daily gain, fever and lameness in beef bulls at the Saskatchewan Central Feed Test Station

Data obtained from the Saskatchewan Central Feed Test Station in Saskatoon, Saskatchewan, Canada were examined for evidence of factors related to average daily gain and the diseases occurring in 326 beef bulls during the 1983-84 test. Average daily gain was found to be significantly associated with breed, pen assignment and initial test weight but was not associated with disease or age upon arrival at the test station. Lameness was associated with breed and initial weight, while fever (suspected respiratory disease) was associated with age. The predicted odds of lameness was approximately seven times greater in the animal with the heaviest as compared to the lightest initial test weight and the predicted odds of fever was approximately five times greater in the youngest as compared to the oldest animal.