Relationship between pre-slaughter stress responsiveness and beef quality in three cattle breeds

Abstract

The relationship between stress responsiveness and beef quality of 40 Nguni, 30 Bonsmara and 30 Angus steers was determined. The L(∗) values, pHu, cooking loss (CL) and Warner-Bratzler shear force (WBSF) were determined. Catecholamine levels were determined from urine samples collected at slaughter. Bonsmara steers had the highest (P<0.05) levels of catecholamines with respective epinephrine, norepinephrine and dopamine concentrations of 10.8, 9.7 and 14.8nmol/mmol. Nguni steers had the lowest (P<0.05) levels of catecholamines, with respective catecholamine concentrations of 5.1, 4.3 and 4.0nmol/mmol. In the Nguni steers, there were significant (P<0.05) correlations between catecholamines and L(∗) and between dopamine and tenderness in meat aged for two days (WBSF2). In the Bonsmara, dopamine was correlated (P<0.05) pHu, WBSF2 and CL. No significant correlations were found in the Angus. Therefore the relationship between stress responsiveness and certain beef quality traits may not be similar in different breeds.

Stress reactivity and its relationship to beef quality in Nguni steers supplemented with Acacia karroo leaves

“…handling on-farm, transport, abattoir environment and handling, and slaughtering processes) separately. The observed concentrations of post-mortem catecholamines in steers that relied on natural pasture alone were higher than those that were reported by Ndlovu et al (2008) and Muchenje et al (2009). The variation could be due to the differences in age-related responses to pre-slaughter stress (Knowles et al, 1997).…”

“…The variation could be due to the differences in age-related responses to pre-slaughter stress (Knowles et al, 1997). Nguni steers in this study were 3 months older at slaughter compared with those used by Ndlovu et al (2008) and Muchenje et al (2009).…”

“…Muchenje et al (2009) obtained low concentrations of catecholamines in urine collected post mortem from Nguni steers compared with the Bonsmara and the Angus breeds. In similar studies, such genotype dissimilarities in behavioural response were attributed to the fact that different animals react differently to the same stressor (O' Neill et al, 2009).…”

“…The magnitude of any negative effect is a function of the type, duration and intensity of the individual stressors, production system and susceptibility of each individual animal to stress (Ferguson and Warner, 2008;Terlouw et al, 2008). The susceptibility of the individual animal to stress is, in particular, influenced by genetics (Ndlovu et al, 2008;Muchenje et al, 2009;O' Neill et al, 2009) and nutrition (Schaefer et al, 2001;Lowe et al, 2002). If losses in beef yield and quality due to ante-mortem stress are to be minimised, it is necessary to understand the effects of these contributory factors and their interaction.…”

“…The Nguni breed has been shown to be resistant to nematodes (Xhomfulana et al, 2009), ticks (Muchenje et al, 2008a) and tick-borne diseases (Marufu et al, 2010), tolerant to pre-slaughter stress (Ndlovu et al, 2008;Muchenje et al, 2009) and produce meat of comparable quality to established beef breeds under rangeland conditions (Muchenje et al, 2008b). Although rangeland energy and mineral supplies in the dry seasons are sufficient to meet the production requirements of Nguni cattle (Mapiye et al, 2010a), they lose -E-mail: cmapiye@yahoo.co.uk body condition and weight in the same season as a consequence of limited protein supply (Mapiye et al, 2010b).…”