Canine mammary gland tumors are the most common neoplasms in intact female dogs. Approximately half of all mammary tumors are malignant, and there is a risk of metastasis, which is associated with a poor prognosis. This study was to evaluate the prognostic factors of canine mammary gland tumors and the risk factors associated with the development of malignant tumors. From 2014 to 2020, 60 dogs with mammary gland tumors that underwent surgical treatment were evaluated in this retrospective study. Tumor size, TNM stage, and histopathological results were prognostic factors for 2-year survival after surgery. Every 10 mm increase in tumor size, increased the risk of death within 2 years after surgery 1.213 times. Dogs with TNM stage IV or V had 8.667 fold risk of death within 2 years after surgery. The 2-year survival rate for dogs with benign tumors was 90.2% and for malignant tumors was 67.3%. Tumor size is the most important prognostic factor for canine mammary gland tumors. As tumor size increased by 10 mm, the risk for development of malignant tumors increased by 1.487 times. Tumors larger than 30 mm are highly likely to be malignant, and metastatic evaluation and wide resection should be considered.

The objective of this study was to identify risk factors for repeat breeder dairy cows and their impact on reproductive performance. The characteristics of 1,504 cows, including their peripartum health, nutrition, production, and reproduction, were collected. Cows with metabolic disorder were significantly more likely (odds ratio [OR], 2.47; p less than 0.001) and cows with clinical endometritis tended to be more likely (OR, 1.35; p less than 0.1) to become repeat breeders than cows without metabolic disorder and clinical endometritis, respectively. Cows initially inseminated more than 80 days after calving were less likely (OR, 0.78; p less than 0.05) to become repeat breeders than cows initially inseminated ≤ 80 days after calving. As a result, repeat breeding in dairy cows resulted in a 90 day longer (p less than 0.0001) mean interval from calving to pregnancy. In conclusion, postpartum metabolic disorder, clinical endometritis, and a short interval from calving to initial insemination were risk factors for repeat breeder dairy cows, resulting in a severely impaired reproductive performance.