Effects of farm management practices and transport duration on stress response and meat quality traits of suckling goat kids.

Studies aimed to assess up to what extent farming and transport previous to slaughtering might affect physiology and meat quality in young goat kids are needed, with the ultimate purpose of promoting practices that minimize stress in these animals. In this regard the effects of on-farm management and transport duration on some physiological responses and meat quality parameters in goat kids were assessed. Two farms representing 'high' and 'low' welfare-friendly management practices were selected. In total, 32 suckling kids were withdrawn from each farm, transported by road for 2 or 6 h, and then slaughtered. Blood samples were collected both on-farm and in the slaughterhouse, and biochemistry, cell counts and haematocrit were determined. After slaughtering, carcass quality parameters were measured. Longissimus dorsi muscle was dissected and pH, colour parameters, water holding capacity and shear force were measured throughout 8-day ageing period. Results indicate that, regardless its duration, transport caused significant effects on some blood parameters suggesting stress in live animals, like glucose, cortisol or creatine kinase. Despite the marked stress status in animals, this condition was not decisively reflected on L. dorsi quality parameters, but some effects were observed regarding fat cover in carcasses and colour parameters. The results suggest that postmortem changes throughout ageing were more decisive in terms of meat quality than stressful management either on-farm or during transport.

Association between functional candidate genes and organoleptic meat traits in intensively-fed beef.

The aim of this study was to assess the associations between the single nucleotide polymorphisms in CAPN1, CAST, DGAT1, FABP4, LEP, RORC and SCD1 genes and the sensory meat quality in an intensively fed commercial population (Charolais, Limousin and Retinta breed). This work carried out analyses on a common Spanish population and evaluated the association between the markers and sensory traits. A total of 161 bulls were allocated to two different feedlots with two different finishing diets. Steaks aged for 7 and 21 days were assessed by both untrained and trained sensory panels. A significant association and allelic substitution effect were observed for markers UoG-CAST, LEP: g.73C>T and SCD1: g.878T>C on different descriptors evaluated by a consumer panel (tenderness and overall acceptability). There are no precedents of these kinds of association studies in a Spanish commercial population. The study suggested that CAST, LEP and SCD1 genes have a potential effect on the different measurements of sensory meat quality.

Carotenoids and fat-soluble vitamins in horse tissues: a comparison with cattle.

Carotenoids are important for human health because of their provitamin A function among other biological actions. Their implication on consumer point of view of cattle products have been widely studied, but very little information is available for horse products. The aim of this study was to study the accumulation of carotenoids, retinoids and tocopherol by HPLC and HPLC-MS analysis in different horse tissues (plasma, milk, adipose tissue and liver) and compare it with that of cattle. Fat color was also studied. Four groups of animals were studied (15 animals within each group): lactating mares (709.82±23.09 kg) and cows (576.93±31.94 kg) reared outdoors; and foals (556.8±25.9 kg, 14 months old) and calves (474.7±36.2 kg, 14 months old) reared indoors. Both mares and foals were from the Hispano-Breton breed, whereas both cows and calves belonged to the commercial crossbred Limousine-Retinta. Differences in plasma and milk carotenoids (P0.05). Both species showed different levels of accumulation of retinoids in the liver, with the foal having better accumulation (P<0.01, P<0.001). These results indicate that there are species-specific differences in the accumulation of carotenoids, retinol and tocopherol, but further studies are required to establish the mechanism of these differences.

Effect of different carotenoid-containing diets on the vitamin A levels and colour parameters in Iberian pigs' tissues: utility as biomarkers of traceability.

Retinol and fat colour parameters in Iberian pigs fed on different carotenoid-containing diets were assessed. Thirty animals in two groups were considered: Iberian breed pigs fed on acorns and grass (Montanera) and on concentrate (Cebo). Carotenoids and retinoids were analysed in the diets and in plasma, liver and perirenal fat of the animals by HPLC and HPLC-MS. Retinol levels in plasma and fat were similar in Montanera and Cebo animals. The utility of retonids and colour parameters as traceability index was also explored. Retinoids in liver classified correctly 93% of the animals according to their diet L* and hab. CIELAB parameters of the perirenal fat discriminated correctly 78.6% of the animals according to their diet. L* values for the Montanera animals were significantly different (P<0.01) from those fed on concentrate. It can be claimed that the liver retinol profile and fat colour parameters can be useful for feeding traceability purposes in Iberian pigs breed in Montanera and Cebo.

Effect of slaughter weight and breed on instrumental and sensory meat quality of suckling kids.

The effects of breed and slaughter weight on chemical composition, fatty acid groups, texture, and sensory characteristics of meat of 141 suckling male kids from 5 Spanish breeds were studied. There was a decrease in texture and lightness and hue angle with the increase of the slaughter weight. Fatty acid composition was correlated with the intramuscular fat content. All the breeds except MO had values of n-6/n-3 ratio below 4, which is the healthy limit recommended, and a low atherogenic index as well as a low intramuscular fat content. A multivariate analysis discriminated light kid, which had the most tender and juicy meat, from heavy kid which had more intense kid and milk odours. Blanca Andaluza and Pirenaica had most tender and juicy meat. The effect of slaughter weight on meat traits should be considered separately for each breed to find the most appropriate meat according to consumers preferences.

Fatty acid profile of three adipose depots in seven Spanish breeds of suckling kids.

Intramuscular, subcutaneous and kidney knob fat depot fatty acid profiles were studied in 104 male suckling kids from seven Spanish breeds: Blanca Andaluza, Blanca Celtibérica, Moncaína, Negra Serrana-Castiza, Pirenaica, Malagueña and Murciano-Granadina. Kids were raised in the traditional production system on mother's milk and slaughtered at around 7kg live weight. Differences were observed between dairy (Malagueña) and meat breeds (Blanca Andaluza, Blanca Celtibérica, Moncaína, Negra Serrana-Castiza, and Pirenaica). Malagueña showed higher monounsaturated and conjugated linoleic fatty acid levels than the other breeds. Highest percentages of saturated fatty acids were observed in meat breeds. For intramuscular fat depot, the range for desirable fatty acids was 66.16-72.27% was. The influence of breed on fatty acid profiles of intramuscular, subcutaneous and kidney knob fat depots studied was evident. Intramuscular fat depot is proposed as a differentiating factor between dairy and meat breed goat kids, but not between meat breed kids.

Suckling kid breed and slaughter weight discrimination using muscle colour and visible reflectance.

Meat colour was evaluated in 141 male suckling kids from five Spanish breeds: Blanca Andaluza (BA), Blanca Celtibérica (BC), Moncaína (MO), Negra Serrana-Castiza (NE) and Pirenaica (PI). Kids were slaughtered at 7.5 and 11.5 kg. pH and colour were measured in the longissimus thoracis et lumborum muscle. pH values did not differ significantly among breeds. Lightness tended to decrease and redness to increase as weight increased. BC and NE at light weight and BC and BA at heavy weight were characterized by greater lightness, chroma and hue. At both weights MO and PI were darker and showed lower values for chroma and hue. BA at light weight and NE at heavy weight were characterized by values that were between those of the former groups for all variables. Discriminant analysis based on colour and pH correctly classified 48.9% of the kids into their breed and slaughter weight.

Meat and fat quality of unweaned lambs as affected by slaughter weight and breed.

Sixty-four male lambs of two Southern Spanish breeds, a dairy breed (Grazalema Merino) and a meat breed (Churra Lebrijana), were used to study the effects of slaughter weight and breed on meat traits and intramuscular and subcutaneous fat composition. Lambs were reared following a traditional production system without weaning and slaughtered when live weight reached 12kg (suckling) or 20kg (light). Meat from suckling lambs of both breeds had lower fat and myoglobin contents, and was more tender and had higher scores for sustained juiciness in the sensory analysis. Fat from light lambs had lower C12:0 and C14:0 levels than fat from suckling lambs. Grazalema Merino meat had higher fat and ash contents, and its fat had higher conjugated linoleic acid content than Churra Lebrijana meat.

Breed effect on carcass and meat quality of foals slaughtered at 24months of age.

In some areas, horsemeat may be considered as an alternative to beef. And recent studies have shown that it may be positive from a nutritional point of view. However, little research has been done on the effects that influence horse carcass traits and meat quality. Breed effect has been studied by comparing two Spanish local breeds (Burguete and Hispano-Bretón) reared following the same traditional production system (24months old). Some differences between breeds were observed for carcass quality measurements and colour parameters. Proximate composition was generally not affected by breed. Burguete foals had lower SFA and MUFA and higher PUFA than Hispano-Bretón ones. PUFA/SFA ratio from both breeds was higher than 0.4 and CLA levels were similar to those found in ruminants.

Estimation of factors influencing fatty acid profiles in light lambs.

Fatty acid composition of intramuscular, intermuscular, subcutaneous, omental and kidney knob fat depots of eighty male light lambs (±21kg live weight) from five Spanish sheep breeds was analysed. Fat depot, anatomical depot location (internal, external and intramuscular), breed (Spanish Merino, Grazalema Merino, Churra Lebrijana, Segureña and Montesina), weaning type (weaning at 45 days after birth or no weaning) and subcutaneous fat thickness factors were analyzed using a statistical model to quantify their contribution to the variation of each fatty acid. Production system was the main factor to explain variations in overall fatty acid profiles (34.68%). However, for several fatty acids and indices (arachidonic, linoleic, PUFA, n-3/n-6) anatomical depot location was the most significant factor. Feeding system explained 65.49% of CLA variance, indicating a strong influence of suckling period length on CLA deposition in lambs' fat. Moreover, due to the lack of interaction between anatomical depot location or depot and breed type or weaning system for total CLA, for future research only one depot would be enough to study the effect of those factors on CLA levels.

Southern Spain lamb types discrimination by using visible spectroscopy and basic physicochemical traits.

The potential for using visible spectroscopy (400-700nm) to classify six types (breed×production system) of lamb meat was investigated. Seven wavelengths namely 400, 410, 420, 450, 510, 610 and 670nm were retained for the discriminant analysis. The basic meat physicochemical traits of Longissimus dorsi were also studied and a model including that information together with the spectra was developed to compare both accuracies. Then, Myoglobin content, water holding capacity, pH, a(∗), 670 and 610nm wavelengths, protein percentage, L(∗), ash content, 450 and 420nm wavelengths and moisture percentage were selected as variables for the development of the discriminant function. The data analysis showed that it was possible to discriminate the lamb types with accuracy around 83% using visible spectroscopy. However these results improved to 95% when using the reflectance together with basic physicochemical traits (12% better than using only the spectra).

The influence of final conditions on meat colour in light lamb carcasses.

Tristimulus values (X, Y, Z) and CIELAB colourimetric coordinates have been measured in m. Longissimus dorsi and m. Triceps braquialis caput longum muscles in 86 light carcasses of lambs from different origins. By applying to these data different mathematical methods (ANOVA, Discriminant Analysis, Principal Components Analysis and Cluster Analysis) we have obtained a good classification of these animals in groups, which has been established according to the different final conditions (feeding or storage). In this way, the percentage of animals accurately classified into their group is 94.2%. Worse results were obtained (84.9%) if the animals were grouped taking their breed or/and origin as a reference.