Effect of gender on meat quality in lamb from extensive and intensive grazing systems when slaughtered at the end of the growing season

Sugar Kelp (Saccharina latissima) Seaweed Added to a Growing-Finishing Lamb Diet Has a Positive Effect on Quality Traits and on Mineral Content of Meat

Supplementing ruminants' diet with seaweed has shown positive effect on meat quality and micronutrients important for human health. The objective of the present study was to investigate the use of Saccharina latissima in a lamb diet to improve the eating quality and nutritional value of meat. Six-month-old female Norwegian White lambs (n = 24) were fed, 35 days pre-slaughter, three different diets: a control (CON) and two seaweed diets (SW); supplemented with either 2.5% (SW1) or 5% (SW2). The quality properties of longissimus thoracis et lumborum (LTL) and semimembranosus with adductor (SM+ADD) muscles were examined. The dietary inclusion of seaweed reduced cooking loss and shear force of lamb meat, although the effect was not significant at both supplementation levels. SW1 fed lambs showed a significantly (p < 0.05) improved meat color stability and antioxidant potential. Seaweed also reduced lipid oxidation (TBARS) and the warm-over flavor in SM+ADD compared to the CON lamb. Seaweed fed lambs showed an increased content of selenium and iodine in LTL, thereby fulfilling the requirements for the label "source of nutrient" and "significant source of nutrient", respectively. An increased arsenic content in LTL was, however, also observed with seaweed inclusion (to 1.54 and 3.09 μg/100 g in SW1 and SW2 group, respectively). While relevant positive effects were found in meat using seaweed in lamb feed, some optimization of this feed approach will be desirable.

Live Weight and Sex Effects on Sensory Quality of Rubia de El Molar Autochthonous Ovine Breed Meat

Simple Summary

Rubia de El Molar is in danger of extinction, and this work is part of a research project funded by the Regional Government of Madrid that aims to know its productive characteristics to prevent its disappearance. The aim of this work is to study the effect of weight and sex on suckling lamb meat sensory characteristics of Rubia de El Molar breed. According to sensory characteristics, two weight groups of animals were detected: light carcasses (10 and 15 kg) and heavy carcasses (20 and 25 kg). Heavy carcasses’ meat was tougher, more elastic, and received lower pleasantness scores than light animals. Sex had a lower effect on meat sensory parameters than weight, and meat from male lambs showed higher flavour intensity and also higher pleasantness scores than female meat.

Abstract

Fifty-six Rubia de El Molar ovine breed lamb carcasses were divided into 8 groups (n = 7 per group) according to weight (10, 15, 20 and 25 kg) and sex (male and female) to study the effect of these factors on meat sensory characteristics, assessed by means of a trained panel. Heavier animals showed a more-springy meat and also received lower scores for pleasantness. Assessors gave lower scores for flavour and pleasantness in female meat. A high correlation was detected between hardness and springiness, number of chews, and pleasantness. Juiciness, greasiness, and flavour were also sensory variates highly correlated. Pleasantness was only correlated to hardness. Changes from 10 to 25 kg did not affect juiciness, greasiness, flavour, and number of chews. There are no significant differences in the sensory quality of lambs slaughtered at 10 and 15 kg live weight, and also between 20 and 25 kg groups. Heavy carcasses (20 and 25 kg) showed a more hard and springy meat than light carcasses (10 and 15 kg). Besides, the 10 and 15 kg animals group received higher scores for pleasantness. This work showed differences in suckling lambs’ meat sensory parameters between Rubia de El Molar and other ovine breeds.

Adapting Seasonal Sheep Production to Year-Round Fresh Meat and Halal Market in Norway

Norway is the largest sheep meat producer among Nordic countries with more than 1.3 million lambs and sheep slaughtered in 2017. The sheep industry is limited by the need for in-house feeding during the winter months. In summer, Norwegian sheep are mainly kept on rangeland pastures, with sufficient feed for almost double the current sheep population. Lambs are slaughtered over a three- to four-month period from September to December with a peak in September–October, providing a surplus of lamb, much of which is subsequently frozen, followed by eight months during which fresh produce is in limited supply. Norwegian consumers eat an average of 5.4 kg of sheep meat per person per year, much of which is purchased as a frozen product. The Muslim (4.2% of the population) preference for year-round halal meat, with an increased demand on the eve of the Muslim meat festival (Eid al-Adha), has the potential to boost demand, particularly in Oslo. This paper provides an overview of the Norwegian sheep farming system, the current market value chains, and the potential to meet the demand for halal meat in Norway (specifically during the Muslim meat festival—Eid al-Adha) to the advantage of both consumers and sheep farmers.

Effect of Flax-Seed Enriched Concentrate Supplementation in Grazing Pramenka Breed Lamb’s Diet on Omental Fat Fatty Acids

This research is aimed at determining the impact of supplementing extensively reared lambs with a limited amount of flax seed enriched-concentrate on the fatty acid profile of the lamb meat (omental fat depot). A total of 96 60-day old Pramenka breed lambs (23.85±3.98 kg live body weight; 60±10 days of age; 42 males and 54 females) raised on pasture with their dams were randomly divided in three experimental groups: control (CON) or extensive rearing group, which did not receive any supplementary feed; concentrate (CC) group, receiving 300 g of a conventional commercial concentrate feed per animal daily, and concentrate-flax seed (CC-FS) group, receiving 300 g/day of the concentrate supplemented with 5% of flax seed. After 60 days of experimental period, 10 lambs were selected (5 males and 5 females) from each group and slaughtered. Omental fat samples were taken and analyzed to determine their fatty acid profile. Significant (P>0.05) differences in the fatty acid profile between CON and CC groups were small. However, enrichment of the concentrate with 5% flax seed increased the percentages of PUFA and n-3 PUFA when compared to both CON and CC groups and thus slightly improved the nutritional characteristics of the omental fat. The effect of sex on the fatty acid profile was only observed for C20:4 n-6 and C20:5 n-3 (P < 0.05).

Effect of breed and castration on production and carcass traits of male lambs following an intensive finishing period

The practice of crossbreeding using a terminal sire and the use of intact rather than castrated animals has the potential to increase the productivity of lambs produced from the hill sheep sector. The objective of this study was to compare the production and carcass characteristics of purebred Scottish Blackface (SB) and Texel cross Scottish Blackface (TXSB) ram and wether lambs fed on a concentrate diet and slaughtered at different ages. Two hundred spring born male lambs (average birth age ± SD 9.53 d) were assigned to a 2 × 2 factorial arrangement with two breeds SB (n = 100) and TXSB (n = 100) and two sexes (wether: n = 100 and ram: n = 100). Lambs were harvested following a 36 d ad libitum concentrate indoor finishing period. The study was carried out over five harvest batches between October and April. The mean ages of the lambs at harvest (n = 40; 20 TXSB and 20 SB lambs) in October, November, January, March, and April were 196, 242, 293, 344, and 385 days, respectively The TXSB lambs were heavier at slaughter than SB lambs (P < 0.001), and ram lambs were heavier at slaughter than wether lambs (P < 0.01). Improved ADG (P < 0.001), lower feed conversion ratio (FCR) (which was calculated by dividing total feed intake by total weight gain; P < 0.001), and higher feed intake (P < 0.05) were recorded in TXSB lambs with consistency across the five harvest time points. Rams had greater ADG (P < 0.001) and FCR (P < 0.05) compared with wether lambs, and no differences were observed between sexes for feed intake. The TXSB (P < 0.001) lambs had higher (P < 0.001) dressing percentages compared with SB, while wether lambs had greater dressing percentages compared with rams. The TXSB lambs had heavier carcass weights (P < 0.001) with higher conformation grades (P < 0.001) and less fat cover (P < 0.001) than SB lambs, while ram lambs had heavier (P < 0.001) carcasses than wether lambs. There was greater fat cover on the loin muscles of SB (P < 0.001) and wether (P < 0.001) lambs compared with TXSB and ram lambs, respectively. The results from this study suggest that TXSB lamb's offer hill sheep farmers a potential strategy for improved lamb production efficiency, while ram lambs offer lamb finishers increased growth rates, higher FCR, and produce a more desirable carcass than do wether lambs.

Fatty Acid Composition of Lamb Liver, Muscle, And Adipose Tissues in Response to Rumen-Protected Conjugated Linoleic Acid (CLA) Supplementation Is Tissue Dependent

The tissue-specific response to rumen-protected conjugated linoleic acid supply (rpCLA) of liver, two muscles, and three adipose tissues of heavy lambs was studied. Twenty-four lambs, 8 months old, divided into 4 groups of 6, were fed at libitum on a ration supplemented without or with a mixture of rpCLA. Silica and hydrogenated soybean oil was the rpCLA coating matrix. The lambs were slaughtered at 11 months of age. Tissues were collected and analyzed for their FA profiles. The dietary rpCLA supplement had no influence on carcass fatness nor on the fat content of the liver and tissues and had little influence on the FA profiles of these tissues. In the adipose tissues, rpCLA increased the proportions of saturated FAs, 18:0 and 18:2t10c12, and decreased the proportions of monounsaturated FAs in the adipose tissues. In muscles, the effects were the opposite. The results suggest that Δ9 desaturase activity is inhibited by the rpCLA mixture in adipose tissues to a greater extent than in the other tissues.

Effects of animal class and genotype on beef muscle nanostructure, pHu, colour and tenderness

Abstract The objective of the study was to determine the effects of animal class and genotype of cattle on Muscularis longissimus thoracis et lumborum (LTL) nanostructure, ultimate pH (pHu), colour and tenderness of beef. We found significant positive relationships between distance travelled (DT) and meat temperature (Tm) (p less than 0.01); lairage duration (LDhr) and lightness of colour (L*) (p less than 0.01); ambient temperature (Ta) and L* (p less than 0.05) and LDhr and yellowness (b*) (p less than 0.05) of beef from Bonsmara cattle. Positive linear relationships were observed between DT and Tm (p less than 0.05) and DT and L* (p less than 0.01) of the non-descript cattle. There were no significant relationships between pre-slaughter stress and other beef quality parameters (pHu, Warner– Bratzler shear force [WBSF], redness [a*] and b*) of Bonsmara, Nguni and non-descript cattle. Muscle fibres differed among class and genotype and had an effect on meat quality. The Bonsmara, non-descript and Nguni cows and heifers had visible skeletal muscle fibres which were thin and long, promising improved tenderness of beef. Genotype and class had significant effects on meat quality parameters (Tm, pHu, L*, a*, b* and WBSF). The first important principal components as they appeared from the analysis were pHu, Tm, L*, a*, b* and WBSF. Therefore, animal class did not affect the nanostructure of beef; instead, meat tenderness was enhanced by the longer and visible muscle fibres. Nguni cattle produced meat of superior quality to that of the Bonsmara and the non-descript cattle.

A model explaining and predicting lamb flavour from the aroma-active chemical compounds released upon grilling light lamb loins

The objective of the work is to understand the role of the different aroma compounds in the perception of the local "lamb flavour" concept. For this, a set of 70 loins (Longissimus dorsi) from approximately seventy day-old Rasa Aragonesa male lambs were grilled and the aroma-active chemicals released during the grilling process were trapped and analyzed. Carbonyl compounds were derivatizated and determined by GC-NCI-MS, whereas other aromatic compounds were directly analyzed by GC-GC-MS. Odour activity values (OAVs) were calculated using their odour threshold values in air. Lamb flavour could be satisfactory explained by a partial least-squares model (74% explained variance in cross-validation) built by the OAVs of 32 aroma-active chemical compounds. The model demonstrates that the lamb flavour concept is the result of a complex balance. Its intensity critically and positively depends to the levels of volatile fatty acids and several dimethylpyrazines while is negatively influenced by the different alkenals and alkadienals. (E,E)-2,4-decadienal and (E)-2-nonenal showed top OAVs.

Effects of zilpaterol hydrochloride on growth performance, carcass characteristics, and wholesale cut yield of hair-breed ewe lambs consuming feedlot diets under moderate environmental conditions

Twenty-four Dorper × Pelibuey ewe lambs initially weighing 25.1 ± 0.6 kg were used in a 34-d feeding experiment and after slaughter to evaluate the effect of zilpaterol hydrochloride (ZH) on feedlot performance, carcass characteristics, and wholesale cut yield. Ewe lambs were individually housed in pens, blocked by initial BW, and assigned randomly within BW blocks to 1 of 2 treatments: 1) control (no ZH) and 2) supplemented with ZH (10 mg/ewe lamb daily) during 32-d and a 2-d withdrawal preslaughter period. Feeding ZH increased (P < 0.01) final BW, ADG, and G:F of ewe lambs, whereas feed intake was unaffected (P = 0.80). Hot and cold carcass weights, dressing percentage, and conformation score were improved (P < 0.001) when ZH was fed. Likewise, LM area was 3.7 ± 0.41 cm(2) larger (P < 0.001) for ZH than control ewe lambs. Feeding ZH did not affect (P ≥ 0.29) cooling loss, carcass length, fat thickness, or KPH. With exception of peritoneum (P < 0.001), head (P = 0.021), and neck (P < 0.001), ZH did not increase (P ≥ 0.12) noncarcass components or wholesale cut yield percentage. A trend to increase (P = 0.060) loin percentage from HCW was observed in lambs supplemented with ZH. In conclusion, feeding ZH to Dorper × Pelibuey ewe lambs improved feedlot performance and also some carcass traits (HCW, cool carcass weight, dressing percentage, and LM area) of economic importance; however, fat deposition was not affected by ZH.