title: Blood biochemical parameters and meat pH of feedlot cattle slaughtered on arrival or after overnight rest at an abattoir.
abstract: The effect of different pre-slaughter rest periods at the abattoir before slaughter on the blood biochemical parameters and meat pH of a number of cattle were studied on 2 occasions, once in summer and once in winter. In the first trial, 42 out of a consignment of 50 and in the second trial, 45 out of a consignment of 54 feedlot-finished oxen were randomly selected and divided into 3 groups each. One group was slaughtered on arrival at the abattoir, a second group 3 h after arrival and the third group was rested in the lairage prior to slaughter the following day. Carcasses were subjected to low voltage electrical stimulation at slaughter. Significant differences between the values obtained at the feedlot and those at the abattoir were found in respect of haematocrit, total plasma protein concentration, plasma glucose, plasma creatine kinase, plasma lipid and cortisol concentration in both the trials. In general, however, no great differences were found between the 3 groups in either of the trials. If any, results in respect of some of the blood parameters were in favour of the groups slaughtered as soon as possible after arrival at the abattoir. No significant differences were found in the initial (35-45 min) and ultimate (24 h) pH of the meat between the 6 groups of slaughtered animals in the 2 trials. Exsanguination appeared to be satisfactory in all groups and no differences between groups were found. It was concluded that feedlot cattle transported to an abattoir over a relatively short distance, need not necessarily be rested in the lairage overnight before slaughter.
authors.affiliation: Department of Physiology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Republic of South Africa.
authors.forename: J F
authors.initials: JF
authors.lastname: Grosskopf
authors.forename: D G
authors.initials: DG
authors.lastname: Meltzer
authors.forename: L W
authors.initials: LW
authors.lastname: van den Heever
authors.forename: F A
authors.initials: FA
authors.lastname: Collett
authors.forename: J J
authors.initials: JJ
authors.lastname: van Rensburg
authors.forename: M S
authors.initials: MS
authors.lastname: Mülders
authors.forename: M S
authors.initials: MS
authors.lastname: Lombard
mesh_terms: D000003:Abattoirs; D000818:Animals; D002417:Cattle / Q000097:blood*; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000032:analysis*; D012146:Rest; D012621:Seasons; D013997:Time Factors