Effects of transportation during the hot season, breed and electrical stimulation on histochemical and meat quality characteristics of goat longissimus muscle

Abstract

The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1-year-old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42 degrees C day time temperature) and non-transported. Animals were blood-sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor-adrenaline and dopamine concentrations (P < 0.05) than non-transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically-stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non-stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non-transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats.

Influence of pre-slaughter transportation and stocking density on carcass and meat quality characteristics of Boer goats

“…Animals lose body weight when subjected to greater energy demands (Warriss 1993). Transportation stress might cause tissue dehydration as well (Degen & Kam 1992;Kadim et al 2010). Kannan et al (2002) demonstrated that transportation and feed deprivation increased stress responses and consequently elevates live weight losses.…”

Effect of season and stocking density during transport on carcass and meat quality of suckling lambs

“…In this sense, Kadim et al (2010) observed on goats that animals transported at high ambient temperature (37°C average) had higher LW losses and lower carcass shrinkage than non-transported animal. However, in our study, carcass quality parameters have not been affected by season or SD, because the temperature occurred during transport in summer or winter were not extreme, with THI values, good indicator of stressful thermal climatic conditions, within the category considered as comfortable (< 70) (Silanikove, 2000).…”

Grouping previously unknown bucks is a stressor with negative effects on reproduction

“…Different letters represent differences between times (P<0.05) and differences between groups are shown as * (P<0.05). Arrow shows the moment immediately before grouping Immediately before grouping, introduced bucks had greater cortisol concentration than resident bucks, probably as a consequence of previous transportation (Kadim et al 2010(Kadim et al , 2014. Therefore, after grouping, it was not possible to discriminate the relative impact of transport and grouping on cortisol response.…”