Effects of Housing, Management, and Health of Dairy Heifers on First-Lactation Udder Health in Southwest Sweden

Abstract

Data on health, management, and housing from birth to first calving were collected for 2,126 heifers on semi-monthly visits made by project veterinarians to 107 dairy herds from southwest Sweden. Additional data were obtained from the official milk- and health-recording program. Factors associated with incidence of veterinarian-treated clinical mastitis (VTCM) in the period 7 d before (d -7) to 30 d after first calving and of elevated cow composite somatic cell count (SCC, > or =200,000 cells/mL) at first test milking after first calving, respectively, were investigated using a 2-level (animal and herd) logistic regression analysis after initial screening by univariate analyses. The incidence risk of VTCM during the complete first lactation (305 d) was 10.8%. Ten percent of the diseased animals had more than 1 case of VTCM and 51% of total cases occurred from -7 to 30 d postcalving. The incidence rate of VTCM during the complete first 305-d lactation was 1.13 cases per 100 cow-mo. In total, 18.1% of the animals had elevated SCC at first test milking (mean 21 d) after calving. Veterinarian-treated clinical mastitis at -7 to 30 d postcalving was associated with higher overall incidence of mastitis in the herd and with reproductive disorders (i.e., retained placenta, endometritis, pyometra, dystocia, or twin birth). The risk of elevated SCC increased with increasing percentage of cows in the herd that, some time during the year, had had an increased udder disease score (chronically increased SCC). Other factors associated with increased risk of elevated SCC were increasing amounts of concentrates fed to 11- to 16-mo-old heifers, moving to confined housing the day of calving instead of earlier, and use of restraint measures at milking. In addition, growth rate from birth to weaning, and several feed-related variables (e.g., amount of concentrates and type of roughage given) were associated with VTCM at -7 to 30 d post-calving or elevated SCC at first test milking in the univariate analyses.

Incidence of subclinical mastitis in Dutch dairy heifers in the first 100 days in lactation and associated risk factors

“…This was comparable with the results of Svensson et al (2006). They found that 18.1% of the heifers had a high SCC (>200.000 cells/mL) at the first test day.…”

“…In European studies, the prevalence of HSCLM ranges between 18.1 and 35% at the start of the lactation (De Vliegher et al, 2001;Svensson et al, 2006). However, the exact percentage of heifers developing heifer mastitis in the Netherlands Incidence of subclinical mastitis in Dutch dairy heifers in the first 100 days in lactation and associated risk factors 2477 is not known.…”

“…Therefore, heifer mastitis may have other etiology than mastitis in multiparous cows. Previously, risk factors such as feeding concentrates, housing, proportion of heifers with mastitis, and using restraint measures during milking, fly control strategy, contact with lactating cows before calving, and udder edema before calving were already identified in Sweden and Belgium (Svensson et al, 2006;Piepers et al, 2011). However, to what extent those risk factors may be applied to the farming system in the Netherlands is unknown.…”

Management factors affecting udder health and effects of a one year extension program in organic dairy herds

“…Langford et al (2008) found management and disease treatment differences between organic and conventional farms in the UK. In general, the quality of management and milking technology plays an important role in udder health control (Østeras and Lund, 1988;Chassagne et al, 2005;Svensson et al, 2006). Straw yard housing was associated with reduced udder health (Peeler et al, 2000;Barnouin et al, 2005) whereas all measures improving barn and cubicle hygiene had a positive impact on udder health (Barkema et al, 1998;Koster et al, 2006;O'Reilly et al, 2006).…”

“…Feeding of the young stock influences their udder health as primiparous cows (Svensson et al, 2006). It is still controversial whether giving infected milk to calves plays a role in the development of subsequent persistent infections in these heifers after parturition (Barto et al, 1982).…”