title: Automatic cluster remover setting affects milk yield and machine-on time in dairy cows.
abstract: The primary objectives of this study were to examine effects of automatic cluster remover (ACR) settings on milk yield and machine-on time, and to describe variation in cow body weight (BW) associated with day of bovine somatotropin (bST) cycle. Automatic cluster removal settings of 0.48, 0.6, and 0.8 kg/min were used to regulate the end of milk removal. The setting was changed every 2 wk for 12 wk and followed the sequence 0.8, 0.6, 0.48, 0.48, 0.6, and 0.8 kg/min. Milk yield, machine-on time, and BW were measured for 60 Holstein cows at each milking. Milk yield averaged 19.7, 19.9, and 19.3 kg/cow per milking for ACR settings of 0.48, 0.6, and 0.8, respectively. There was a 2.5% reduction in milk yield at the high setting, but yields were similar for the others. Machine-on time was 6.3, 5.9, and 5.6 min for ACR settings of 0.48, 0.6, and 0.8, respectively. There was an 11.1% reduction in milking time between the 0.8- and 0.48-kg/min settings. The middle ACR setting yielded a shorter milking time than the low setting without reducing production. Milk yield and cow BW increased over the 14-d bST cycle, peaking by d 8, and then declining through d 14. Automated collection of milk yield, milking time, and BW at each milking can be used to establish normal patterns for individual animals, which could be useful in making management decisions.
authors.affiliation: Department of Dairy and Animal Science, The Pennsylvania State University, University Park, 16802, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Magliaro
authors.forename: R S
authors.initials: RS
authors.lastname: Kensinger
mesh_terms: D000818:Animals; D001835:Body Weight; D002417:Cattle / Q000502:physiology*; D003612:Dairying / Q000295:instrumentation* / Q000379:methods; D005260:Female; D013006:Growth Hormone / Q000008:administration & dosage; D007774:Lactation; D008414:Mastitis, Bovine / Q000453:epidemiology; D013997:Time Factors
chemical_list: C073294:growth hormone, bovine; D013006:Growth Hormone