M Wieland, C O Paulrud, K Kakoulis, M E Spellman, H Somula, A Singh
{"title":"一项观察性研究调查乳头状况与临床乳腺炎风险的关系。","authors":"M Wieland, C O Paulrud, K Kakoulis, M E Spellman, H Somula, A Singh","doi":"10.3168/jds.2025-27316","DOIUrl":null,"url":null,"abstract":"<p><p>The objectives were to investigate the association between machine milking-induced teat tissue changes and the occurrence of clinical mastitis in Holstein dairy cows. We conducted 2 separate prospective cohort studies at 1 commercial dairy farm in New York State to study the association of machine milking-induced short-term changes (STC, trial 1) and machine milking-induced long-term changes (LTC, trial 2) with clinical mastitis occurrence. Each trial consisted of four 3-wk periods. On d 1 of each period, STC and LTC were assessed through visual inspection and manual palpation. Short-term teat tissue changes were assessed based on teat discoloration, the condition of the teat base, and the consistency of the teat end and categorized into a binary variable (STC present or absent). Long-term teat tissue changes were categorized into 4 groups as follows: no callosity present (score 1), callosity ring present with no or only mild roughness (score 2); callosity ring and roughness present with keratin fronds extending 1 to 3 mm from the teat orifice (score 3); and callosity ring present with excessive keratin fronds extending ≥4 mm from the teat orifice (score 4). Data on clinical mastitis occurrence was extracted from the herd management software. We used the first clinical mastitis event of a quarter for each 3-wk trial period and applied a 14-d gap to define a new mastitis case within a quarter between 2 trial periods. In trial 1, STC was documented in 6,110 of 66,702 cases (9.2%) over the four 3-wk periods, The frequency distribution of LTC in trial 2 was as follows: score 1 in 7,348 of 61,624 cases (11.9%), score 2 in 48,553 cases (78.8%), score 3 in 5,514 cases (8.9%), and score 4 in 209 cases (0.3%). We documented 944/66,702 (1.4%) clinical mastitis cases at the quarter level during trial 1 and 866/61,624 (1.4%) cases during trial 2. Generalized linear mixed models with a logit link and a binomial distribution were used to test if machine milking-induced teat tissue changes were associated with clinical mastitis occurrence. In trial 1, we analyzed 66,702 quarter-level observations from 5,094 cows. We found no significant association between STC and clinical mastitis occurrence. Compared with a quarter with a teat without STC, the odds (95% CI) of clinical mastitis were 1.22 (0.95-1.59). In trial 2, we used 61,624 quarter-level observations from 4,998 cows. We found no significant association between LTC and clinical mastitis occurrence. Compared with a quarter with a teat with a smooth end (score 1), the odds of a clinical mastitis case were 1.02 (0.77-1.36) for score 2, 1.19 (0.84-1.69) for score 3, and 2.14 (0.80-5.71) for score 4. We concluded that in the study cohort presented here, machine milking-induced teat tissue changes were not associated with the occurrence of clinical mastitis.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.4000,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"An observational study investigating the association of teat condition with clinical mastitis risk.\",\"authors\":\"M Wieland, C O Paulrud, K Kakoulis, M E Spellman, H Somula, A Singh\",\"doi\":\"10.3168/jds.2025-27316\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>The objectives were to investigate the association between machine milking-induced teat tissue changes and the occurrence of clinical mastitis in Holstein dairy cows. We conducted 2 separate prospective cohort studies at 1 commercial dairy farm in New York State to study the association of machine milking-induced short-term changes (STC, trial 1) and machine milking-induced long-term changes (LTC, trial 2) with clinical mastitis occurrence. Each trial consisted of four 3-wk periods. On d 1 of each period, STC and LTC were assessed through visual inspection and manual palpation. Short-term teat tissue changes were assessed based on teat discoloration, the condition of the teat base, and the consistency of the teat end and categorized into a binary variable (STC present or absent). Long-term teat tissue changes were categorized into 4 groups as follows: no callosity present (score 1), callosity ring present with no or only mild roughness (score 2); callosity ring and roughness present with keratin fronds extending 1 to 3 mm from the teat orifice (score 3); and callosity ring present with excessive keratin fronds extending ≥4 mm from the teat orifice (score 4). Data on clinical mastitis occurrence was extracted from the herd management software. We used the first clinical mastitis event of a quarter for each 3-wk trial period and applied a 14-d gap to define a new mastitis case within a quarter between 2 trial periods. In trial 1, STC was documented in 6,110 of 66,702 cases (9.2%) over the four 3-wk periods, The frequency distribution of LTC in trial 2 was as follows: score 1 in 7,348 of 61,624 cases (11.9%), score 2 in 48,553 cases (78.8%), score 3 in 5,514 cases (8.9%), and score 4 in 209 cases (0.3%). We documented 944/66,702 (1.4%) clinical mastitis cases at the quarter level during trial 1 and 866/61,624 (1.4%) cases during trial 2. Generalized linear mixed models with a logit link and a binomial distribution were used to test if machine milking-induced teat tissue changes were associated with clinical mastitis occurrence. In trial 1, we analyzed 66,702 quarter-level observations from 5,094 cows. We found no significant association between STC and clinical mastitis occurrence. Compared with a quarter with a teat without STC, the odds (95% CI) of clinical mastitis were 1.22 (0.95-1.59). In trial 2, we used 61,624 quarter-level observations from 4,998 cows. We found no significant association between LTC and clinical mastitis occurrence. Compared with a quarter with a teat with a smooth end (score 1), the odds of a clinical mastitis case were 1.02 (0.77-1.36) for score 2, 1.19 (0.84-1.69) for score 3, and 2.14 (0.80-5.71) for score 4. We concluded that in the study cohort presented here, machine milking-induced teat tissue changes were not associated with the occurrence of clinical mastitis.</p>\",\"PeriodicalId\":354,\"journal\":{\"name\":\"Journal of Dairy Science\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":4.4000,\"publicationDate\":\"2025-09-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Dairy Science\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://doi.org/10.3168/jds.2025-27316\",\"RegionNum\":1,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"AGRICULTURE, DAIRY & ANIMAL SCIENCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Dairy Science","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.3168/jds.2025-27316","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"AGRICULTURE, DAIRY & ANIMAL SCIENCE","Score":null,"Total":0}
An observational study investigating the association of teat condition with clinical mastitis risk.
The objectives were to investigate the association between machine milking-induced teat tissue changes and the occurrence of clinical mastitis in Holstein dairy cows. We conducted 2 separate prospective cohort studies at 1 commercial dairy farm in New York State to study the association of machine milking-induced short-term changes (STC, trial 1) and machine milking-induced long-term changes (LTC, trial 2) with clinical mastitis occurrence. Each trial consisted of four 3-wk periods. On d 1 of each period, STC and LTC were assessed through visual inspection and manual palpation. Short-term teat tissue changes were assessed based on teat discoloration, the condition of the teat base, and the consistency of the teat end and categorized into a binary variable (STC present or absent). Long-term teat tissue changes were categorized into 4 groups as follows: no callosity present (score 1), callosity ring present with no or only mild roughness (score 2); callosity ring and roughness present with keratin fronds extending 1 to 3 mm from the teat orifice (score 3); and callosity ring present with excessive keratin fronds extending ≥4 mm from the teat orifice (score 4). Data on clinical mastitis occurrence was extracted from the herd management software. We used the first clinical mastitis event of a quarter for each 3-wk trial period and applied a 14-d gap to define a new mastitis case within a quarter between 2 trial periods. In trial 1, STC was documented in 6,110 of 66,702 cases (9.2%) over the four 3-wk periods, The frequency distribution of LTC in trial 2 was as follows: score 1 in 7,348 of 61,624 cases (11.9%), score 2 in 48,553 cases (78.8%), score 3 in 5,514 cases (8.9%), and score 4 in 209 cases (0.3%). We documented 944/66,702 (1.4%) clinical mastitis cases at the quarter level during trial 1 and 866/61,624 (1.4%) cases during trial 2. Generalized linear mixed models with a logit link and a binomial distribution were used to test if machine milking-induced teat tissue changes were associated with clinical mastitis occurrence. In trial 1, we analyzed 66,702 quarter-level observations from 5,094 cows. We found no significant association between STC and clinical mastitis occurrence. Compared with a quarter with a teat without STC, the odds (95% CI) of clinical mastitis were 1.22 (0.95-1.59). In trial 2, we used 61,624 quarter-level observations from 4,998 cows. We found no significant association between LTC and clinical mastitis occurrence. Compared with a quarter with a teat with a smooth end (score 1), the odds of a clinical mastitis case were 1.02 (0.77-1.36) for score 2, 1.19 (0.84-1.69) for score 3, and 2.14 (0.80-5.71) for score 4. We concluded that in the study cohort presented here, machine milking-induced teat tissue changes were not associated with the occurrence of clinical mastitis.
期刊介绍:
The official journal of the American Dairy Science Association®, Journal of Dairy Science® (JDS) is the leading peer-reviewed general dairy research journal in the world. JDS readers represent education, industry, and government agencies in more than 70 countries with interests in biochemistry, breeding, economics, engineering, environment, food science, genetics, microbiology, nutrition, pathology, physiology, processing, public health, quality assurance, and sanitation.