Suckling lamb meat is traditionally produced in Mediterranean Europe. Breed can affect the quality of the lamb carcass and meat. This study is aimed at comparing the carcass and meat quality between suckling lambs from a local and a non-native dairy breed, Churra and Assaf. Churra is included in the Spanish Protected Geographical Indication (PGI) ‘Lechazo de Castilla y León’, whereas Assaf is not. However, Assaf breeders have requested the inclusion of the breed in the PGI. Carcasses and meat from 16 male lambs (eight Churra and eight Assaf) were used in this study. The lambs were all raised under an intensive rearing system and fed on a milk substitute to minimise maternal influence. The carcasses were evaluated for conformation, fatness, joint and leg tissue proportions and the meat was analysed for composition (i.e. proximate composition, iron, haematin, fatty acids and volatiles) and technological quality traits (i.e. texture, water holding capacity, colour and lipid stability). Churra carcasses were larger than Assaf carcasses. However, the proportions of commercial joints and main tissues did not differ between breeds. Cavity and intermuscular leg fat, but not total leg fat, were higher in Churra carcasses. Churra meat showed a higher proportion of n-6 fatty acids, higher redness and better colour stability during aerobic storage. In contrast, Assaf lamb was more resistant to lipid oxidation after cooking. This is a preliminary study to measure the influence of breed on a wide range of quality characteristics in Churra and Assaf suckling lamb carcass and meat. It may be of relevance for breeders, consumers and food policy makers, setting the basis for future studies that include larger commercial populations.

Chamarito lamb was recognized as a quality brand in Spain in April 2010 and this meat is highly appreciated in the local market, but little is known about how a short fattening period may affect final product quality. Twenty lambs, ten from the Ternasco category and ten from the suckling lamb category, were slaughtered and their carcass characteristics compared. All animals were weighed at birth, weaning and before slaughter, and average daily gain was calculated. Cold carcasses were weighed and bruising score, carcass conformation and carcass fatness were noted. The left back of each carcass was separated for dissection. The meat pH, cooking and thawing losses, texture, colour and fatty acid composition were measured on M. longissimus samples. Production traits and meat quality variables were analysed fitting a one-way model with the fixed effect of mean lamb age at harvest. The conformation and degree of fatness of Ternasco-type lambs was not significantly different from suckling lambs but the pH values 24.00 hours post-mortem in muscle (pHult) of the former was slightly higher. The fatty acid profile of suckling lambs was more suitable for a healthy human diet.

In this study, we investigated the effects of maternal gestation and/or lactation diets supplemented with extruded linseed (rich in 18:3n-3) on growth performance and long-chain polyunsaturated faaty acid (PUFA) accumulation in muscle tissues of suckling lambs. A total of 36 dairy ewes were fed a control diet (CON) and a diet containing linseed (LIN) during the last 8 weeks of gestation and/or the first 4 weeks of lactation. The four dietary treatments consisted of the following gestation/lactation feeding treatments: CON/CON, CON/LIN, LIN/LIN or LIN/CON. The lambs born from ewes fed the aforementioned diets were reared exclusively on milk and were slaughtered at 4 weeks of age. Profiles of ewes’ milk fatty acids and that of intramuscular fat (IMF) of leg muscles from lambs were determined. Compared with the CON/CON, LIN/CON offspring tended to grow slower and to have reduced cold carcass weights. Moreover, the LIN supplementation only in the prepartum period (LIN/CON) resulted in greater PUFAn-3 accumulation in the IMF compared with the CON/CON offspring due to increased 20:5n-3 (1.20 v. 0.64 mg/100 mg of total FA), 22:5n-3 (1.91 v. 1.46;) and 22:6n-3 (1.25 v. 0.89) contents, respectively. Compared with the CON/CON diet, providing LIN only during lactation (CON/LIN) caused a greater PUFAn-3 content in the IMF mainly due to a greater 18:3n-3 (1.79 v. 0.75 mg/100 g total FA) concentration. Continuous PUFAn-3 exposure, both via the maternal gestation and lactation diet, had no additive effects on PUFAn-3 accumulation in tissues. The results suggest that linseed, as an 18:3n-3 source, seems to be more efficient in increasing long-chain PUFAn-3 in fetal than in suckling lamb tissues.

Enhancing healthy fatty acids (FAs) in ewe milk fat and suckling lamb tissues is an important objective in terms of improving the nutritional value of these foods for the consumer. The present study examined the effects of feeding-protected lipid supplements rich in unsaturated FAs on the lipid composition of ewe milk, and subsequently in the muscle and subcutaneous adipose tissues of lambs suckling such milk. Thirty-six pregnant Churra ewes with their new-born lambs were assigned to one of three experimental diets (forage/concentrate ratio 50 : 50), each supplemented with either 3% Ca soap FAs of palm (Control), olive (OLI) or fish (FO) oil. The lambs were nourished exclusively by suckling for the whole experimental period. When the lambs reached 11 kg BW, they were slaughtered and samples were taken from the Longissimus dorsi and subcutaneous fat depots. Although milk production was not affected by lipid supplementation, the FO diet decreased fat content (P<0.001), whereas the OLI milk FA profile resembled that of the Control diet. In contrast, although FO drastically diminished the contents of stearic and oleic acids (P<0.001), all the saturated even-numbered carbon FAs from 6:0 to 14:0 increased (P<0.05). FO also produced the highest levels of c9,t11-18:2 (2.21%) and n-3 FAs, 20:5 n-3 (0.58%), 22:5 n-3 (0.48%) and 22:6 n-3 (0.40%). The high levels of trans-11 18:1 (7.10%) obtained from the FO diet would suggest that Ca soaps only confer partial protection in the rumen. In contrast, the lack of significant differences in trans-10 18:1 levels (P>0.05) and other trans-FAs between Control and FO treatments would indicate that FO treatment does not alter rumen biohydrogenation pathways under the assayed conditions. Changes in dam milk FA composition induced differences in the FA profiles of meat and fat depots of lambs, preferentially incorporated polyunsaturated FAs into the muscle rather than storing them in the adipose tissue. In the intramuscular fat of the FO treatment, all the n-3 FAs reached their highest concentrations: 0.97 (18:3 n-3), 2.72 (20:5 n-3), 2.21 (22:5 n-3) and 1.53% (22:6 n-3). In addition, not only did FO intramuscular fat have the most cis-9, trans-11 18:2 (1.66%) and trans-11 18:1 (3.75%), but also the lowest n-6/n-3 ratio (1.80) and saturated FA content were not affected. Therefore, FO exhibited the best FA profile from a nutritional point of view.