Search

Crossbreeding is an important tool to improve sheep meat production. The objective of the present work was to evaluate the characteristics of the carcass and meat of Pampinta lambs and their cross with Hampshire Down. For the study, 23 whole male lambs were used, 11 of the Pampinta breed and 12 Pampinta crosses with Hampshire Down. The lambs were checked healthily and weighed weekly. At the mother's foot they grazed on triticale (Triticosecale aestivum; L.) greens with vetch (Vicia sativa). They were weaned with an average weight of 20.2 (4.22) kg live weight (LW) and a WC of 2.5 on average (scale from 1 to 5). They entered a pen in a single group for 84 days. On the day of slaughter, the PV Pampinta 37.25 (1.76) kg was recorded; Hampshire Down 37.25 (1.81) kg, hot carcass weight; shaping and fattening; the fat (pelvic-renal) for the category of more than 13 kg of carcass; hot runner pH; LC and LP; AG and AT and compactness indices calculated from morphometric measurements and weight. After 12 h of maturation, PCE and pH were measured and EGD was determined in longissimus thorasis muscle; thickness of the subcutaneous tissue at the GR point; AOB; FC with the Warner-Brätzler shear; CRA and PPC. The animals were classified according to the letters S, E, U, R, O and P; according to great muscular development up to a marked muscular deficiency, and 5 degrees were stipulated for the completion, from the lack of fat coverage to the excessive presence. There was no effect of breed (P = 0.05) on all carcass characteristics. Analysis of variance (ANOVA) was used for data analysis. These results reflect differences in the conformation of the carcass. [ABSTRACT FROM AUTHOR]

Highlights • Early assessment of carcass traits and meat cuts are important to support management decisions in production systems. • Linear regression and machine learning methods were used to predict carcass traits and commercial meat cuts in lambs. • Moderate to high prediction accuracies were observed across methods. • Results indicate that the support vector machine algorithm is a potential alternative to the linear regression model. Abstract The aim of this study is to investigate the performance of multiple linear regression and machine learning methods to predict carcass traits and commercial meat cuts in lambs using non-invasive in vivo measurements. Bayesian networks were also investigated as an alternative method for feature selection. Phenotypes from 74 nondescript breed lambs were measured. A leave-one-out cross-validation strategy was performed and predictive ability statistics (R2, RMSE) were assessed. Moderate to high prediction accuracies were observed, with R2 values across models ranging, from 0.36 to 0.88 for carcass traits and 0.65 to 0.84 for meat cuts predictions. Results suggest that support vector machine algorithm is a potential alternative to the traditional multiple linear regression model. Further, the results of this study suggest that both stepwise and Bayesian network procedures could be useful as pre-selection tools of the input variables in non-parametric approaches and the best method for feature selection may be trait and model dependent. [ABSTRACT FROM AUTHOR]

Highlights • CT level was not sufficiently high to inhibit PUFA biohydrogenation. • CT reduced indole but not skatole l in perirenal fat of lambs. • Sheepy odour in lamb meat depends on dietary protein level. Abstract The study aimed to evaluate the interaction between dietary crude protein (CP) and condensed tannins (CT) on the growth performance, carcass composition and meat quality of ram lambs. Twenty-four White Alpine lambs were fed a basal diet consisting of 56% birdsfoot trefoil (BT) silage and 44% hay (67.1% grasses, 4.3% legumes and 28.6% herbs). In addition, lambs were offered either a barley concentrate to reach the predicted protein requirements (BP) or a barley and soybean meal concentrate to extend the CP level 20% above the requirements (HP). The diets were either untreated (BP−; HP−) or treated (BP+; HP+) with the CT-binding polyethylene glycol (PEG). Lambs fed HP− and HP+ diets had greater (P < 0.001) average daily feed intake (ADFI) and average daily gain (ADG) than lambs fed BP− and BP+ diets. Consequently, slaughter weight and cold carcass weight were greater (P ≤ 0.05) in HP− and HP+ groups. Despite similar slaughter weight, lambs fed BP− and HP− diets had lower (P < 0.05) cold carcass weight compared to lambs fed BP+ and HP+ diets. The skatole concentrations in the perirenal fat were not affected by the dietary treatments. The observed interaction between CP level and CT concentration resulted in lower (P < 0.05) indole level in perirenal fat of lambs fed the HP− diet, attributed to the greater CT intake. No effects of dietary treatments were detected on the flavour scores of the meat whereas the loin from lambs fed HP− and HP+ diets had lower 'sheepy' odour compared with the loin of those fed the BP− and BP+ diets. These findings let us conclude that at elevated intake, CT reduced the indole but not skatole level in the perirenal fat. The lack of effect of BT at basal and high dietary CP level on the other traits investigated might be explained by the rather low CT content. [ABSTRACT FROM AUTHOR]

Rations (DM basis) for spring-born male lambs consisting of concentrates ad libitum (CON), 50:50 (50% concentrate:50% forage), and forage ad libitum (FORG) were evaluated across feeding periods of three durations (36, 54, and 72 d). Lambs on CON diets were offered ad libitum access to concentrate along with 400 g of fresh weight silage (daily), while 50:50 diets were offered 0.9 and 3.0 kg of concentrate and silage, respectively. Lambs on FORG were offered ad libitum access to 25.5% DM silage. These rations were fed to 99 spring-born male Texel cross Scottish Blackface lambs which were assigned to a 3 × 3 factorial arrangement. Lambs were slaughtered following completion of their respective treatments. Lambs fed CON diets had greater ADG, FCE, and carcass weight (P < 0.001) and carcasses with greater conformation score (P < 0.001) than lambs fed 50:50 or FORG diets. Duration of feeding had no effect on production variables across all three concentrate inclusion levels. It was concluded that the inclusion of concentrates is needed to adequately finish lambs fed indoors. Feeding lamb's 50:50 diets resulted in modest responses and may be a viable option for finishing lambs or to maintain growth in lambs when the cost of concentrate feed is high relative to the financial return on the lamb meat. [ABSTRACT FROM AUTHOR]

Meat quality and carcass characteristics are becoming more relevant for the sheep breeding programs because of their economic value. Understanding the genetic basis for these traits and its relationship with standard traits is necessary for this to be accomplished. Genetic and phenotypic parameters were estimated for 33 growth, carcass and meat quality traits using a large and unique data set from a variety of terminal sire sheep breeds and composites. This is the most comprehensive study to date of genetic parameter estimates for carcass and meat quality traits in New Zealand sheep and includes many traits that are difficult or expensive to measure and novel traits such as number of rib pairs. Heritability estimates ranged from 0.01 for meat redness at 168 h after display to 0.44 for ultrasonic eye muscle depth. Most genetic correlations among growth and carcass traits were favourable and moderate to high. However, some genetic antagonisms such as those between carcass fatness and carcass weight were observed indicating that selection to produce heavier carcasses would also result in fatter carcasses. The genetic correlations among meat quality traits were quite variable. Marbling and tenderness were favourably but weakly genetically correlated, indicating that indirect selection gains by selecting only for traditional traits (i.e. growth and carcass traits) would be small and it is recommended that both be included in a breeding program in order to make greater genetic progress in these traits. The genetic correlations among growth/carcass and eating quality traits were moderate to low; however, some genetic antagonisms were observed, such as carcass fatness with marbling and meat redness, indicating that a stronger emphasis on selection for leanness could affect meat quality traits and consequently consumer eating satisfaction. The heritability estimates and phenotypic variances for the carcass and meat quality traits of New Zealand sheep populations suggest that most traits, apart from pH and meat yellowness, have sufficient phenotypic and genetic variation to enable substantial genetic gains to be achieved through selection. The genetic parameters presented in this study provide a valuable reference to design and/or update a terminal sire breeding program emphasizing meat quality traits. It is important to note that unfavourable genetic correlations identified in this study were low to moderate in magnitude, making it practical to select for favourable genetic progress in all traits or at least to maintain commercially acceptable levels for some traits, if they are measured and balanced in a selection index. [ABSTRACT FROM AUTHOR]

The objective of the study was to compare ad libitum or restricted access of whole shelled corn (WSC) versus ad libitum alfalfa pellets, and sex of the lamb, on lamb growth and performance. Ewe (n = 48) and wether (n = 48) lambs were blocked by sex and stratified by initial weight to pen. The three diets offered were ad libitum access of a WSC diet, 85% access of ad libitum WSC diet, or an ad libitum access of an alfalfa pellet diet. There were four lambs per pen, and eight replicate pens per dietary treatment. Ewe and wether lambs were removed from the study when pens reached an average weight of 59.0 and 63.5 kg, respectively. Average daily gain (ADG) of lambs offered the ad libitum WSC diet was greater (P < 0.05) than lambs offered the restricted WSC and alfalfa pellet diets, which resulted in fewer (P < 0.01) days on feed for lambs offered ad libitum WSC. Lambs offered alfalfa pellets had a greater (P < 0.01) daily dry matter intake (DMI) than lambs offered the WSC diets. Wether lambs had greater (P < 0.01) daily DMI when compared with ewe lambs. Gain to feed ratio was greatest (P < 0.01) for lambs offered ad libitum access to WSC, followed by lambs offered restricted WSC, and lambs offered the alfalfa pellet diet. The cost of whole shelled corn was $0.15/kg, the cost of alfalfa pellets was $0.60/kg, and the cost of supplements was $0.51/kg on an as-fed basis. The resulting feed cost of gain was greatest (P < 0.01) for lambs offered alfalfa pellets, followed by lambs offered restricted WSC, and lastly lambs offered ad libitum WSC. Lambs offered the WSC diets produced a greater hot carcass weight (HCW; P < 0.01) and greater (P < 0.01) dressing percent when compared with lambs offered alfalfa pellets. Lambs consuming ad libitum WSC had a greater amount (P < 0.05) of kidney fat when compared with lambs consuming a restricted diet of WSC or ad libitum access to alfalfa pellets. Lambs consuming either of the WSC diets produced a greater (P < 0.05) amount of visceral fat when compared with lambs offered alfalfa pellets. Lambs offered alfalfa pellets had greater tissue weight of the reticulum (P < 0.05), omasum (P < 0.01), and total digestive tract (P < 0.05), consistent with the lower dressing percentage observed. Lambs offered WSC had greater (P < 0.05) backfat and body wall thicknesses, loin marbling scores, and yield grades (P < 0.01) when compared with lambs offered alfalfa pellets. Wether lambs had a greater (P < 0.05) final BW and HCW when compared with ewe lambs. Overall, lambs offered ad libitum WSC grew more efficiently at a lower cost of gain while producing carcasses with greater amounts of fat, whereas lambs offered alfalfa pellets had a lower dressing percentage and a greater total digestive tract weight. [ABSTRACT FROM AUTHOR]

Forty Kermani fattening male lambs (21 ± 1.4 kg body weight (BW) and six months old) were assigned to a completely randomized design to determine the effects of feeding pistachio by-products silage with wasted date (PBSWD) on dry matter intake (DMI), live weight gain, feed conversion and carcass characteristics. Two thousand kg of fresh pistachio by-products (PBP) were mixed thoroughly with 400 kg Mazafati wasted date and ensiled for 2 months. Experimental diets were: (1) control (without PBSWD); (2) diet containing 7% PBSWD; (3) diet containing 14% PBSWD and (4) diet containing 21% PBSWD. All diets were formulated to contain 60% concentrate and 40% forage (dry matter (DM) basis). The lambs were divided into four equal groups and fed the diets for a 90-day experimental period. At the end of the experiment, all animals were slaughtered on the same day. Ensiling of PBP with wasted date increased the DM and metabolisable energy (ME), but decreased ( P < 0.05) the percentages of crude protein, ether extract, total tannins and phenolic compounds. Lambs fed the 14 and 21% PBSWD diets had more ( P < 0.05) DMI than those fed control diet. Feeding 21% PBSWD increased ( P < 0.05) final BW, weight gain, the weights of warm and cold carcass, liver, loin, lean meat, reproductive system and small intestine, and the eye muscle area,. Lambs fed 21% of PBSWD had higher ( P < 0.05) back fat depth than lambs fed control diet. Results showed that feeding 21% PBWDS to fattening lambs increased their feedlot performance and lean meat yield. [ABSTRACT FROM AUTHOR]

The effect of carcass weight, age at slaughter and sex on some chemical components was evaluated in twenty-two Boutsiko lambs (twelve females and ten males). Chemical composition of meat was expressed as percentage of fat, protein, collagen and moisture content. Measures of the four chemical components were taken by carcass cuts included shoulder, leg, racks, kidney, rear flank, breast ribs and scrag-end. Results have shown that the percentage content of fat, protein, moisture and collagen are in a good level compared to the other sheep breeds and E.U. Directives. Regression analysis showed that among the three independent variables only carcass weight had significant effect on the content of fat, protein and moisture, while the age at slaughter was the only factor which has an impact on the value of collagen. The significant positive relation of carcass weight with fat content and its negative relation with moisture and protein is an indication that lessening the weight by a small amount will have comparatively favorable results in the chemical quality of meat through the reduction of fat and the increasing of moisture and protein content. Small reduction of age at slaughter will further improve the level of collagen, which is the basic parameter affecting the tenderness of the meat. Reduction of carcass weight and age at slaughter means less meat in the market and lower returns for producers. [ABSTRACT FROM AUTHOR]

This study investigated the effects of maize maturity at harvest and dietary inclusion rate of maize silage on feed intake, average daily gain (ADG) and carcass traits of growing ram lambs fed high-concentrate diets. Precision-chopped maize was harvested at two stages of maturity (Early: dough stage and Late: dent stage) and ensiled as round bales. Early or late cut maize silage was fed as the sole forage or together with grass silage, to 40 ram lambs in each of two consecutive years. The four treatments in each year were: (1) early cut maize silage as 50% of the forage dry matter (DM) proportion (E50), (2) early cut maize silage as 100% of the forage DM proportion (E100), (3) late cut maize silage as 50% of the forage DM proportion (L50) and (4) late cut maize silage as 100% of the forage DM proportion (L100). The proportion of forage in each of the diets was on average 42% on a dry matter (DM) basis and the concentrate consisted of dried distillers’ grains plus solubles, rolled barley and cold-pressed rapeseed cake in year 1 (Y1) or heat-treated rapeseed expeller in year 2 (Y2). Daily DM intake (DMI) was 1.24 and 1.40 kg, averaged over treatments, in Y1 and Y2, respectively. Increasing the dietary inclusion rate of maize silage from 50 to 100% of the forage DM proportion resulted in increased DMI in Y1 ( P <0.05) and increased carcass fatness in Y2 ( P <0.01), whereas increased maturity stage at harvest tended to result in increased DMI in Y2 ( P <0.10). Feed conversion ratio (FCR; kg DMI per kg ADG), was lower for the treatments E100 and L50 than for E50 and L100, respectively ( P <0.01) in Y2. The body weight of the lambs increased linearly over time, in both years. In conclusion, maize silage can replace grass silage in the diets of high-producing lambs. Increased metabolizable protein (MP) to metabolizable energy (ME) ratio of the diet increased ADG of the lambs. Also, increased ADG decreased mega joule ME intake per kg ADG, in finishing lambs. [ABSTRACT FROM AUTHOR]

Investigated was the effect of isomerised grapeseed oil supplementation on carcass composition and body fat in lambs and fat content of their meat. Grapeseed oil alkaline isomerisation and crystallisation with urea resulted in synthesis of conjugated dienes amounting to linoleic acid (CLA) 77.6% FFA. The enrichment of fattening lambs' rations with the additive at 18 g/animal/day did not influence body weight gain, carcass weight and Longissimus dorsi parameters (weight, width, depth). However, it reduced body fatness by 19 to 25%, and decreased the fat content of muscle tissue by 17 to 22 percentage points. [ABSTRACT FROM AUTHOR]

This research was carried out to determine fattening performance with some body and carcass traits of Malya lambs at the open sheepfold. 8 Malya male lambs were used in the study. Lambs were averagely fattened at 20 kg of live weights (2.5 months of age) and 150 g alfalfa was daily given to the lambs in addition ad-libitum concentrate feed for 58 days. Daily live weight gain, total feed intake and feed conservation ratio of the per Malya lamb were found 319 g, 155.4 kg and 4.38, respectively. In addition to these, both pH, hardness and colour values of Longissimus dorsi and colour values of subcutaneous fat were identified. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate relationships between mitochondrial respiratory chain complex activities, feed efficiency, and carcass traits in sheep. A group of Ghezel male lambs sired by a single ram were randomly allotted to individual pens. The lambs were fed ad libitum with a fattening diet containing 30% roughage (corn silage and alfalfa hay) and 70% concentrate for 70 d to individually phenotype each lamb for feed conversion ratio (FCR), adjusted FCR (aFCR), and residual feed intake (RFI). The lambs were then humanely killed and the liver, abdominal fat, pelvic fat, cardiac fat, warm carcass weight, and cold carcass weight, as well as the cross-sectional area of the LM and the fat depth over the 12th rib, were determined. A portion of LM was obtained to determine mitochondrial protein and respiratory chain complex activities (complexes I to V). Statistical analysis was carried out based on lambs exhibiting high and low RFI (n = 8), FCR (n = 8), or aFCR (n = 8) phenotypes. The lambs exhibiting the high-RFI phenotype consumed 110 g more feed daily (P < 0.05) than did the phenotype exhibiting low RFI, with no difference in ADG. Conversely, there was no difference in feed intake between the low- or high-FCR groups, but sheep exhibiting the low-FCR phenotype gained 70 g more (P < 0.05) per day compared with those exhibiting the high-FCR phenotype. It was determined that all 5 respiratory chain complex activities were greater (P < 0.05) in sheep exhibiting the low-RFI phenotype compared with those exhibiting the high-RFI phenotype, with significant (P < 0.001) negative correlation coefficients between RFI and respiratory chain complex activity. When efficiency was assessed using FCR, only activities of respiratory chain complexes III, IV, and V were less (P < 0.05) in the low-FCR phenotype compared with the high-FCR phenotype, and there were no differences (P > 0.1) in respiratory chain complex activities between groups when FCR was adjusted for metabolic BW (aFCR). There were no differences (P > 0.1) in carcass traits among any of the feed efficiency phenotypes. The results suggest that the inclusion of respiratory chain complex activities in breeding programs may be helpful in selecting for sheep exhibiting the low-RFI phenotype. [ABSTRACT FROM AUTHOR]

The article offers information on a study that deals with liveweight gain and carcass characteristics of lambs on perennial pastures. These characteristics were compared with annual pastures and supplementation. The study focused on 54 second-cross lambs allocated to four treatments including perennial pasture, annual pasture with hay and grain (AP), AP with flaxseed and AP with flaxmeal.

The objective of this experiment was to determine if growth, carcass composition, and myofiber characteristics of lambs were affected by heterozygosity for a myostatin mutation (g+6723G>A) when offered differing allowances of feed administered with or without ractoparnine. Heterozygote [MS TN A/G (n = 40)] and homozygote wildtype [MS TN G/G (n = 39)] castrate male lambs were individually fed ad libitum (HI; 1.8 x estimated MEm) or a restricted allowance (LO; 1.1 x estimated MEm) of a diet (191 g of CP/ kg of DM and 12 MJ of ME/kg of DM), supplemented with (0.4 mg/kg of BW) or without the α-adrenergic agonist ractopamine (RAC or NO RAC) for 47 d. The lambs were scanned by computed tomography at the beginning and completion of the feeding experiment to calculate composition of lean, fat, and bone in the carcass component of the body. The MSTN A/G HI intake lambs had significantly greater total daily carcass growth (P = 0.045) and loin eye depth (P = 0.022) and tended to have a greater daily growth of lean (P = 0.09) in the carcass, compared with MSTN G/G HI intake lambs. Conversely, MSTN A/G LO intake lambs tended to have less daily lean deposition (P = 0.09), significantly less total daily carcass growth (P = 0.045), and had a greater percentage of type TIX myofibers (P < 0.01) and total myofiber area (relative area) of type IIX myofibers (P 0.013). The inclusion of RAC increased final BW (P = 0.03) and ADG (P = 0.02), percentage of type IIC (P < 0.001) and IIA (P = 0.012) myofibers, cross-sectional area of types I (P = 0.04) and IIAX (P = 0.04) fibers, and the relative area of type IIC (P = 0.003) and IIA (P = 0.01) myofibers in the LM. The experiment demonstrated that including RAC in the diet of lambs increased final BW and ADG, but not HCW, and increased proportion of type IIC and hA myofibers and cross-sectional area of type I and IIAX myofibers. Our data suggest that RAC and the heterozygous myostatin mutation act together to increase growth of muscle on a high plane of nutrition. The experiment also demonstrated that poor nutritional background of lambs heterozygous for the myostatin mutation may negatively influence their growth rates and myofiber characteristics. [ABSTRACT FROM AUTHOR]

This study was carried out to compare the growth, slaughter and carcass characteristics of Morkaraman (Pure) and Kivircik X Pure (F1) (Cross-bred) lambs in semi-intensive condition. At this study 20 Pure and 22 Cross-breed lambs were used for growth traits; 6 male lambs from each group were slaughtered for slaughter and carcass traits. Growth was investigated from the birth to 150th day. The lambs were fed with alfalfa and lamb fattening feeds (days 45). The least squares mean of birth weight and 30, 60, 90, 120 and150th day weight were 4.06±0.10 and 4.25±0.11, 9.93±0.26 and 8.76±0.26 (P<0.01), 16.87±0.45 and 14.40±0.45 (P<0.001), 23.21±53 and 21.72±0.52 (P<0.05), 29.62±0.64 and 26.69±0.63, 34.93±0.80 and 35.85±0.79 kg. Dressing percentages were 48.49 and 45.03% (P<0.01); the percentages of leg were 28.36 and 32.23% (P<0.001); shoulder were 17.04 and 17.51%; back were 5.67 and 7.38% (P<0.001); loin were 6.14 and 6.26%; others were 24.31 and 28.62% (P<0.001); kidney were 0.63 and 0.72% (P<0.001); kidney-pelvic channel fat were 0.64 and 0.95 (P<0.01); internal fat were 1.21 and 1.73%; fat tail were 15.72 and 4.64% (P<0.001). The percentages of lean meat in the leg were 64.20 and 65.57%; fat were 15.55 and 13.42%; bone were 20.25 and 21.02%. The percentages of lean meat in the shoulder were 65.64 and 63.00%; fat were 13.55 and 13.90%; bone were 20.82 and 23.11%. The percentages of total meat in the carcass were 48.01 and 55.09% (P<0.05); fat were 16.21 and 16.96%; bone were 19.55 and 21.44%; and fat percentages in the tailed carcass were 31.93 and 21.55% for pure and Cross-breed lambs respectively. In conclusion; it has been though that Kivircik rams can be utilized for breeding with Pure Morkaraman ewes, commonly found in the region, to obtain lambs with high quality meat at slaughtering age without adaptation problem; and desired lean meat can be obtained via grazing in addition to cross breeding. [ABSTRACT FROM AUTHOR]

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 cm2 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. [ABSTRACT FROM AUTHOR]

The objectives of this experiment were to determine the effects of replacing ground corn with soybean hulls (SH) in high-concentrate diets on the growth (56-d period), carcass characteristics, and eating behavior of feedlot lambs. Sixty-four Santa Inês ram lambs (18.3 ± 2.8 kg of BW and 69 ± 5 d of age) were assigned to a randomized complete block design experiment with 8 blocks and 4 diets. The control diet contained 10% coastcross (Cynodon sp.) hay, 70% corn, and no SH (SH0) in the dietary DM. In the remaining diets, SH replaced corn at the rate of 15 (SH15), 30 (SH30), or 45% (SH45) of the original corn concentration, resulting in 0, 10.5, 21.0, or 31.4% SH in the dietary DM. Dry matter intake increased linearly (P < 0.01) when SH replaced ground corn (1.0, 1.0, 1.1, and 1.1 kg/d for SH0, SH15, SH30, and SH45, respectively). There was no effect on ADG of lambs, with values of 276, 278, 282, and 287 g for SH0, SH15, SH30, and SH45, respectively. Feed efficiency decreased linearly (P < 0.01) with SH inclusion. Carcass measures were not affected by SH as a replacement for ground corn. Eating time, expressed as minutes per day and minutes per gram of NDF, showed a quadratic effect (P < 0.05), whereas no effect was observed when expressed as minutes per gram of DM. Rumination, in minutes per day, was not influenced by dietary SH inclusion, but a linear decrease (P < 0.01) was observed when this variable was expressed as minutes per gram of NDF. Soybean hulls can replace up to 45% of the ground corn (31.4% of SH in the dietary DM) in high-concentrate diets fed to feedlot lambs without negative effects on ADG and carcass measures. The linear decrease in feed efficiency (11.6% reduction from SH0 to SH45) suggests that optimal dietary SH inclusion rates should be dictated by the relative costs of SH and corn. [ABSTRACT FROM AUTHOR]

Abstract: Little scientific information is available that evaluates wheat middlings (WM) as corn grain substitute in lamb diet. The objective of this work was to evaluate the effect of feeding WM in total mixed rations (TMR) on lamb performance and carcass characteristics. Forty Comisana breed male lambs (13±0.5kg BW) were allocated randomly to two isocaloric and isonitrogenous diets. Two pelleted TMR were formulated: control diet contained 400g/kg of dry matter (DM) of corn as main starch source, whereas experimental diet contained 600g/kg DM of WM. Lambs were slaughtered after fifty days of feeding trial and carcass data were collected. In order to evaluate in vivo digestibility of TMR, four adult Comisana rams were placed in metabolic cages and their individual faeces and urine were collected, and indicated differences for NDF and ADF fractions. Results from growth trial of lambs showed that final live weight and gain as well as feed conversion ratio were improved by WM in diet (P=0.035). In slaughter trial, none of the parameters studied were influenced by dietary treatment, except for slaughter weight and cold-carcass dressing that were improved in lambs fed WM (P=0.047 and P=0.042, respectively). Additionally, WM diet had no effect on lamb carcass traits. As result, WM maintained lamb performance and had no negative effect on lamb performance and carcass traits. Maximizing the use of WM may become economically feasible for lamb feeders when prices turn favorable compared to conventional dietary ingredients such as corn. [Copyright &y& Elsevier]

Abstract: The aim of this study was to quantify the hygienic status of a lamb slaughterhouse by means of multivariate statistical analysis, to demonstrate how the microbiological data could be exploited to improve the lamb slaughter process by constructing control charts and to evaluate the potential effect of an intervention step such as steam application on the microbiological quality of lamb carcasses. Results showed that pelt removal and evisceration were hygienically uncontrolled. TVC and Enterobacteriaceae progressively increased from the stage ‘after pelt removal of hind and forelegs/before final pulling’ to the stage ‘after evisceration/before pluck removal’ thus indicating possible deposition of microorganisms during these operations. It seems that the processing stages of freshly produced carcasses were better distinguished by Enterobacteriaceae, with evisceration contributing mostly to the final Enterobacteriaceae counts. Application of steam during the lamb slaughter process reduced microbial counts without adverse effects on the organoleptic characteristics of the carcasses. Moreover, the construction of control charts showed that decontamination with steam contributed to the maintenance of an in control process compared to that before the application of steam, suggesting the potential use of steam as an intervention step during the lamb slaughter process. [Copyright &y& Elsevier]

Abstract: This study was conducted to evaluate the effects of using different dietary forage-to-concentrate ratios on growth performance and carcass characteristics of eighty Chall male fat-tailed lambs, averaging 165±15 (SD) days of age and body weight of 38.4±4.8 (SD) kg, randomly assigned to four diets containing alfalfa hay-to-concentrate ratios (DM basis) of 70:30 (C30), 50:50 (C50), 30:70 (C70), 10:90 (C90). Metabolizable energy (ME) contents were, 9.12. 9.96, 10.67, and 11.34MJ/kg dry matter (DM) and crude protein (CP) contents were 143, 152, 161, and 174g/kg for the C30, C50, C70, and C90 diets, respectively. Sixteen lambs (4 lambs/treatment) were slaughtered at the end of feeding period (84 days). Dry matter intake and feed conversion ratio (FCR) (i.e., kgDM/kggain) decreased linearly (P<0.001) as concentrate level increased in the diet. However, a linear increase (P<0.001) for ME intake and a quadratic increase for average daily gain (ADG, P<0.001) and final body weight (P<0.01) were observed with increasing dietary concentrate. Slaughter weight, eye muscle area, and weights of lean, bone, neck, shoulder, rack–loin, leg, skin, head, lung, and spleen were not affected by the experimental diets. However, as dietary concentrate increased, a linear increase for dressing percentage, feet weight (P<0.001), and backfat thickness (P<0.02), a quadratic increase for empty body weight (EBW, P<0.02), weights of hot and cold carcass (P<0.001), subcutaneous fat (P<0.02), total fat (P<0.01), brisket–flank (P<0.04), and tail fat (P<0.001), a linear decrease for weights of liver (P<0.01), and heart (P<0.05), and a quadratic decrease for lean-to-fat ratio (P<0.02) were observed. This study indicates that in Chall fat-tailed lambs the increase of dietary concentrate (up to 700g/kg) improves growth rate, FCR and dressing percentage with negative effect on carcass lean-to-fat ratio. [Copyright &y& Elsevier]

Carcasses of Tsigai breed and Suffolk and German Blackface crossbred lambs fattened in an intensive system were subjectively (according with EUROP system) and objectively evaluated. After conformation, carcasses of Suffolk crossbred lambs were included in U and R, German Blackface ,c Tsigai in R, and carcasses from Tsigai pure breed in R and O classes. After the layer of fat, carcasses of Suffolk crossbred lambs were included in 2 and 3 classes, German Blackface x Tsigai in 3, and carcasses from Tsigai breed in 3 and 4 classes. Suffolk and German Blackface crossbred lambs had a higher (P<0.001) muscle proportion in all carcass parts than Tsigai breed lambs. Tsigai breed had a higher fat proportion than Suffolk and German Blackface crossbred lambs in almost all carcass pieces, but significant differences were founded in carcass rests (P<0.001). It was concluded that Suffolk and German Blackface rams could be used for crossing with Tsigai ewes to produce lambs with better carcass conformation and leaner carcass. [ABSTRACT FROM AUTHOR]

Market lambs from the state fair of Virginia (n = 172) were ultrasonically evaluated by 4 scan technicians and 3 image interpreters to determine accuracy of ultrasonic estimates of loin muscle area (ULMA), backfat thickness (UBF), and body wall thickness (UBW). Lambs were initially scanned at the preferred magnification setting of each technician; 2 chose 1.5 x and 2 chose 2.0 x. Lambs were then scanned a second time for ULMA and UBF with machine magnification settings changed from 1.5 to 2.0x, or vice versa, midway through the second scan. Lambs were then slaughtered, and analogous measurements [carcass loin muscle area, carcass backfat thickness, and carcass body wall thickness (CBW)] were recorded on chilled carcasses. Pooled, residual correlation coefficients within technicians and interpreters between ultrasonic measurements from the first scan and carcass measurements were 0.66 for loin muscle area, 0.78 for backfat thickness, and 0.73 for body wall thickness, but were reduced to 0.43, 0.69, and 0.50, respectively, by inclusion of linear effects of carcass weight in the model. Mean bias for technicians and interpreters ranged from -1.30 to -2.66 cm2 for loin muscle area, -0.12 to -0.17 cm for backfat thickness, and 0.14 to -0.03 cm for body wall thickness; prediction errors ranged from 1.86 to 2.22 cm2, 0.12 to 0.14 cm, and 0.35 to 0.38 cm, respectively. Pooled correlations between repeated measures were 0.67 for ULMA, 0.79 for UBF, and 0.68 for UBW at the same magnification and 0.73 for ULMA and 0.76 for UBF across different magnification settings. Mean differences between repeated measures were more variable among technicians and interpreters than statistics comparing ultrasound to carcass measures. Standard errors of repeatability ranged from 1.61 to 2.45 cm2 for ULMA, 0.07 to 0.11 cm for UBF, and 0.36 to 0.42 cm for UBW. The effect of changing magnification setting on technician and interpreter repeatability was small for UBF and ULMA. The accuracy of prediction of CBW from UBW was similar to that achieved for backfat thickness; further assessment of the value of ultrasonic measurements of body wall thickness in lambs is warranted. These results indicate that ultrasound scanning can reliably predict carcass loin muscle area and backfat thickness in live lambs and, accordingly, has value in selection programs to improve composition. Development of certification standards for US lamb ultrasound technicians based on results of this study and others is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Thirty-two intact male Pelibuey lambs with an average weight of 21.2kg were randomly assigned to four treatment rations in a completely random design. The four experimental rations contained incremental levels of dry waste mycelium: 0, 2.7, 5.4 and 8.1%. The study was 75 days long, with 15 days for adaptation of lambs to their pens and a 60-day experimental period in which dry matter (DM) intake, daily weight gain, and feed efficiency were determined. At the end of the study, lambs were slaughtered, and their carcasses weighed and marbling scores determined. Results show a quadratic effect on DM intake (P =0.035) and ADG (P =0.006). Both DM intake and ADG first increased before declining as mycelium level increased in the diet. Gain:feed decreased linearly (P <0.001) with an increase in waste mycelium in the diet. Carcass characteristics, such as hot and chilled carcass weight and hot and chilled dressing percent, and carcass marbling score, were not affected (P >0.10). Marbling score of the carcasses ranged from traces to modest marbling. [Copyright &y& Elsevier]

Altering the influence of the testicles of male lambs is used to manipulate growth and body composition. To determine the effects on carcass weight and consequently returns to farmers, an analysis was undertaken from studies in the scientific literature in which animals were slaughtered at the same time. Each dataset was treated as if it were a random event and a model of sex type (including ram, cryptorchid, and wether) was fitted. Rams, cryptorchids and wethers slaughtered on the same date had similar carcass weights. Cryptorchid carcass weights ranged from 95-102%, and wethers 87-107%, of the weight of ram carcasses. Based on this range in responses to altering testicular function, at an intermediate carcass weight of 17.5 kg and at $4/kg, returns from cryptorchids ranged from $3.50 less than to $1.40 more than rams. Similarly, returns from wethers ranged from $9.10 less than to $4.90 more than rams. In conclusion, the carcass weight benefits of not castrating ram lambs are variable and, depending on lamb prices, the financial gains will be small when slaughtered at the same age. However, these results need to be interpreted in light of other animal husbandry and animal welfare requirements and expectations. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of crude glycerin on performance and carcass characteristics in finishing weather lambs. Thirty black–faced, Suffolk–cross weather lambs (44.1 ± 5.6 kg initial BW) were stratified and blocked by BW to 1 of 5 individually fed, isocaloric, isonitrogenous dietary treatments containing 0, 5, 10, 15, or 20% crude glycerin (88% pure) on a DM basis. Diets were fed once daily for ad libitum consumption and contained 15% chopped hay, approximately 25% dried distillers grains with solubles, and the specified treatment combination of cracked corn replaced with increasing amounts of crude glycerin. Wethers were weighed on 14–d intervals and were selected for slaughter when they reached an approximate 12th–rib fat depth of 0.51 cm (28 to 84 d on trial). Carcass characteristics were collected after a 48–h chill. Dry matter intake (linear, P = 0.004) and ADG (quadratic, P = 0.05) increased with increasing concentrations of glycerin in the diet during the first 14 d of the feeding period. Similarly, C:F tended to increase quadratically (P = 0.06) with increasing concentrations of crude glycerin in the diet during the first 14 d. However, there were no differences among treatments for final BW, days on feed, or cumulative DM1, cumulative ADO, and cumulative C:F (P> 0.11). Body wall thickness, dressing percent, HCW, LM area, flank streaking, leg score, conformation score, quality grade, yield grade, and percent boneless, closely trimmed retail cuts did not differ (P ↕ 0.21). Adding up to 15% crude glycerin to finishing weather diets improved feedlot performance, particularly during the first 14 d, without any concomitant effect on carcass characteristics. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of crude glycerin on performance and carcass characteristics in finishing weather lambs. Thirty black–faced, Suffolk–cross weather lambs (44.1 ± 5.6 kg initial BW) were stratified and blocked by BW to 1 of 5 individually fed, isocaloric, isonitrogenous dietary treatments containing 0, 5, 10, 15, or 20% crude glycerin (88% pure) on a DM basis. Diets were fed once daily for ad libitum consumption and contained 15% chopped hay, approximately 25% dried distillers grains with solubles, and the specified treatment combination of cracked corn replaced with increasing amounts of crude glycerin. Wethers were weighed on 14–d intervals and were selected for slaughter when they reached an approximate 12th–rib fat depth of 0.51 cm (28 to 84 d on trial). Carcass characteristics were collected after a 48–h chill. Dry matter intake (linear, P = 0.004) and ADG (quadratic, P = 0.05) increased with increasing concentrations of glycerin in the diet during the first 14 d of the feeding period. Similarly, C:F tended to increase quadratically (P = 0.06) with increasing concentrations of crude glycerin in the diet during the first 14 d. However, there were no differences among treatments for final BW, days on feed, or cumulative DM1, cumulative ADO, and cumulative C:F (P> 0.11). Body wall thickness, dressing percent, HCW, LM area, flank streaking, leg score, conformation score, quality grade, yield grade, and percent boneless, closely trimmed retail cuts did not differ (P ↕ 0.21). Adding up to 15% crude glycerin to finishing weather diets improved feedlot performance, particularly during the first 14 d, without any concomitant effect on carcass characteristics. [ABSTRACT FROM AUTHOR]

Effects of zilpaterol hydrochloride (ZH) on growth performance trial (30-day period), and carcass traits of finishing lambs were evaluated. Twenty-eight male Rambouillet lambs (32.7±2.6 kg body weight) were randomly assigned to diets with: 0, 5.3, 10.6, and 15.9 mg ZH/kg dry matter (DM). Average daily weight gain, hot and chilled carcass dressing, muscle conformation, hindquarters width, major and minor torax width, crude protein, and ash of Longissimus dorsi (LD) increased linearly as ZH level increased. Feed conversion was linearly improved, and perirenal fat, leg length, and fat of LD were linearly reduced as ZH level increased. Hot and chilled carcass dressing, dorsal fat, area, and sherar forces values of LD, were cubically affected by ZH level, which at 15.9 mg/kg DM offered the best values. The ZH supplementations at 15.9 mg/kg DM showed positive effects on growth performance and carcass traits. [ABSTRACT FROM AUTHOR]

Abstract: Data on 630 crossbred lamb carcasses were used to estimate genetic parameters for a number of carcass measures, fitting a multivariate animal model using restricted maximum likelihood. Carcass measures included: cold carcass weight (CCW), EUROP conformation and fat class scores (MLC-CF), primal joint weights predicted using MLC-CF and several carcass linear and area measures obtained by Video Image Analysis (VIA-DM). Heritability estimates for subjective carcass traits (MLC-CF and primal joint weights predicted using MLC-CF) were low (0.05–0.17), whereas those for objective carcass traits (linear and area measurements on the carcass from VIA) were moderate to high (0.20–0.53). Phenotypic correlations between MLC-CF and VIA-DM were in general low (0.01–0.51) and genetic correlations were slightly higher (−0.04–0.81), when interpreting their absolute value. The results suggest that selection for shorter carcasses (VIA lengths) will be associated with improved conformation but a reduction of the total CCW. Likewise there was a trend in the genetic correlations between conformation and carcass widths which indicated that conformation could also be improved by selection for wider carcasses as measured by VIA which in turn will also imply an increase in CCW. The genetic correlations between VIA-DM and fat class score were only significantly different from zero for the VIA measurement for the leg area (r g =−0.73). Length traits were highly correlated with each other, with an average genetic correlation of 0.84. Positive genetic correlations (0.47–0.85) were found between widths measured on the shoulders and chest with hind leg widths. The areas measured on the carcass were moderately to highly correlated with each other (0.54–0.90). In general, genetic correlations which were found to be significant between areas, lengths and widths were moderate to high and positive. Phenotypic and genetic correlations along with heritabilities of the VIA-DM from crossbred lambs, suggest that using this VIA dimensional information in the evaluation of purebred terminal sire breeds is likely to improve conformation on crossbred lambs. [Copyright &y& Elsevier]

Abstract: Fourty-eight Churra Tensina single male lambs were used to evaluate the effect of different feeding systems on carcass composition and predict the carcass tissue composition from joint composition and carcass measurements. Four treatments were studied: GR, unweaned lambs continuously grazing with ewes; GR + S, the same as the previous group, but lambs had free access to concentrate; DRL-GRE, lambs remained indoors with free access to concentrate and ewes grazed for 8 h/day, thereafter remaining with lambs; and DRL, lambs and ewes were kept in confinement, they had free access to concentrate and dry unifeed respectively. In the DRL-GRE and DRL groups lambs were weaned when 45 days old. Lambs were slaughtered at 22–24 kg live weight. Commercial joints from the half left carcass were obtained, recorded and dissected to determine carcass tissue composition. The feeding system had an effect on the proportion of the carcass tissue composition. GR treatment showed higher muscle (M) (p <0.05) and bone (B) (p <0.001) percentages, and a lower total fat (F) percentage (p <0.001) than the rest of treatments. Hence it revealed higher M/F (p <0.01) and lower M/B (p <0.05) and subcutaneous fat/intermuscular fat ratios (SF/IF; p <0.001). Carcass composition predictions were more accurate for grams than for percentages. In predictions from joint composition, pelvic limb was the most accurate joint for grams (R 2 =0.84, R 2 =0.68, and R 2 =0.77 for muscle, bone, and fat, respectively) as well as for percentage (R 2 =0.65, R 2 =0.56, and R 2 =0.73 for muscle, bone, and fat, respectively). Predictions from carcass measurements were greater in muscle and fat grams (R 2 =0.87 and R 2 =0.86 for muscle and fat, respectively) than in percentage (R 2 =0.58 and R 2 =0.73 for muscle and fat, respectively). Equations to predict carcass tissue that include carcass measurements are a simple method to assess accurately saleable muscle yield from different lamb feeding systems without involving carcass damage. [Copyright &y& Elsevier]

Abstract: Ten male lambs of each of Rahmani (R) and Ossimi (O) were used to study the growth and carcass characteristics within their first year of age (360 days). After suckling period (4 months), lambs were fed on the regular ration. During the course of the experiment, body weight (BW) was recorded monthly accompanied by blood sampling to determine IGF-I. Four lambs from each breed were slaughtered at 270 and 360 days of age, and Longissimus lumbarum (L. lumbarum) at the 9th, 10th and 11th ribs and Biceps femoris (B. femoris) muscles were separated to be used for chemical analysis and histological study. Breed had no effect on the growth curve of the two studied breeds. Chemical analysis indicated that (O) had higher fat (0.9%, P <0.0001) and lower (0.3%, P <0.01) moisture compared to (R), with no difference in protein and ash contents. The concentration of IGF-I was almost similar in both breeds up to day 270 of age, and then it was higher in (R). Number of fibers per bundle was higher (P <0.05) in (O) than in (R) by 6.1%, while, the other histological traits were similar in the two studied breeds. Chemical analysis indicated that lambs slaughtered at 360 days of age had lower (0.7%, P <0.0006) moisture and higher fat (17.3%, P <0.0001) compared to day 270. Up to day 270 of age, IGF-I concentration was <500 ng/ml before increasing to >500 ng/ml up to the end of the experiment. No effect of age was observed on the studied histological traits. L. lumbarum muscle contained higher protein (4.2%, P <0.0001), fat (104%, P <0.0001) and ash (10%, P <0.001), while moisture was less (5.6%, P <0.0001) compared to B. femoris muscle. B. femoris muscle was higher (P <0.0001) in number and diameter of fibers, bundle and stroma sectional areas relative to L. lumbarum by 38.2, 78.8, 53.2 and 23.8%, respectively. [Copyright &y& Elsevier]

Effects of docking on carcass fat characteristics were studied in fat-tailed sheep. Male lambs were randomly divided into 2 groups. One group was docked after birth using rubber rings, and the tails of the other group were left intact (control). After weaning, 20 lambs from each group were divided into 2 subgroups; one subgroup was fed with a normal energy diet (10.25 MJ/kg ME) and the other one with a high-energy diet (11.42 MJ/kg ME) for 84 days. At the end of the fattening period, 28 lambs were slaughtered for determination of warm carcass weight (WCW) and other carcass characteristics. At 24 h postmortem samples of meat, omental fat, and caudal fat were taken from chilled (4 °C) carcasses for the assessment of fatty acid (FA) composition. No significant difference (P > 0.05) was observed in WCW and omental fat between carcasses of docking and control lambs, but lambs on 2 types of energy diets showed a significant difference (P < 0.05). Under these circumstances, docked lambs produced leaner carcasses than intact lambs (P < 0.05). Diet energy had a significant effect on average daily gain and daily feed intake (P < 0.05). Results showed that the predominant FA in body fat was oleic acid and a significant difference was observed for percentage of FA composition between fat in different parts of body (P < 0.05). [ABSTRACT FROM AUTHOR]

Abstract: A total of 7074 crossbred lambs, produced by mating crossbred Mule ewes with terminal sire rams were used in this study. Of these, 630 were scanned using a Video Image Analysis (VIA) to estimate carcass quality traits. Genetic parameters for average daily gain (ADG), scanning live weight (SW), ultrasonic measures of muscle (UMD) and fat (UFD) depths, cold carcass weight (CCW) and VIA measurements of primal carcass joint weights (LEG, CHUMP, LOIN, BREAST and SHOULDER) were estimated using multivariate animal models. Additionally, VIA traits were evaluated under a repeatability model, considering the primal joints as repeated measures of the same trait. Direct heritability estimates were low to moderate (0.08–0.26) for VIA measurements of primal joints. Repeatability estimates for VIA traits were high (>0.90). Moderate to high heritability estimates (0.25–0.55) were found for performance traits (ADG, SW, UMD and UFD) and CCW. Genetic correlations between VIA traits and ADG were strong (0.75–0.93). Most of the VIA traits were highly correlated to SW (0.60–0.97). UFD was significantly negatively correlated with UMD (−0.22), ADG (−0.18) and CCW (−0.18). The results of this study suggest that selection on performance and carcass traits, measured by VIA, could possibly improve primal meat yield of carcass cuts without increasing the overall carcass fatness. High repeatability estimates of VIA traits and moderate heritabilities of the most valuable carcass joints suggests that including VIA information in breeding programs would be useful in order to improve carcass quality. [Copyright &y& Elsevier]

The objectives of this study were to study the relationship between in vivo ultrasound measurements and cold carcass measurements at 4 anatomical points of the backbone, and to establish regression equations to estimate carcass composition within the cold carcass weight range for Ternasco lambs (8 to 12.5 kg) by using ultrasonic measurements taken at a single location. Measurements of subcutaneous fat and skin thickness and of muscle depth and width were taken over the 10th to 11th and 12th to 13th thoracic vertebrae and the 1st to 2nd and 3rd to 4th lumbar vertebrae. These measurements were taken at 2 and 4 cm from the nearest end of the LM to the backbone and at 1/3 of the LM width with the probe perpendicular to and parallel to the backbone. The left sides of the carcasses were dissected into muscle, fat, and bone. Body weight (22.6 kg) and cold carcass weight (10.8 kg) were representative of Ternasco light lambs. Muscle depth measured at 2 cm, 4 cm, and 1/3 of LM width remained regular, with slight ups and downs along the spine. All the pairs of in vivo ultrasound and cold carcass measurements were significantly different (P < 0.05) and had small correlations. All the ultrasound measurements of muscle depth at any location or at any distance to the backbone were less than their equivalent cold carcass measurements, with differences ranging from 0.8 to 5.9 mm. Differences between ultrasound fat thickness + interface (US_FDGI) and cold carcass fat thickness were less than differences between ultrasound fat thickness and cold carcass fat thickness, ranging from -0.9 to -1.0 mm for the former and from -2.1 to -0.5 mm for the latter. The small differences in absolute values between US_FDGI and cold carcass fat thickness suggest that US_FDGI is the best measure of the real fatness level of the lambs. The best prediction equations for muscle, bone, and fat were developed with in vivo ultrasound data measured at the 1st to 2nd lumbar vertebrae perpendicularly to the backbone, but they had limited predictive value. To predict the muscle content of carcass, BW and muscle depth were included, and they explained 59% of variation. Fifty-one percent of total fat was predicted by BW and fat thickness, whereas only 17% of the variation in bone was predicted by 2 fat-related variables. The BW of lambs was an important predictor to improve regression equations but ultrasound measurements were the most important variables when a narrow range of BW was used. [ABSTRACT FROM AUTHOR]

Abstract: Forty-eight single male lambs were used to evaluate the effect of feeding systems on carcass characteristics and fat depots of Churra Tensina light lambs. Four treatments were studied: GR, lambs and ewes were continuously grazing, no concentrate was available to them and lambs were unweaned; GR+S, as the previous one, but additionally lambs had free access to concentrate; DRL−GRE, lambs remained indoors with free access to concentrate and ewes grazed during 8 h a day, thereafter remaining with lambs; DRL, lambs and ewes were kept always in confinement, ewes had free access to dry unifeed and lambs to concentrate. In DRL−GRE and DRL lambs were weaned at 45 days old. When lambs reached 22–24 kg of live-weight they were slaughtered. Feeding system had effect on growth rates (p <0.05), age (p < 0.001) and live-weight at slaughter (p < 0.01), carcass weight (p < 0.001), dressing percentage (p < 0.001), fatness thickness (p < 0.01) as well as on the subjective classification parameters, as carcass conformation score (p < 0.001), fatness degree (p < 0.01) and KKCF score (p < 0.01), having the GR lambs lower values than the rest of treatments. Nevertheless, carcasses from grazing animals were classified within the normal ranges for Ternasco commercial category similar to drylot systems. Treatment had effect on pelvic (p < 0.01) and carcass compactness (p < 0.001) being GR carcasses less well conformed. Feeding system affected the total body fat depots (p < 0.01), presenting GR the lowest amount. In all treatments, carcass fat depot was greater than internal fat depots (abdominal, pelvic and renal) (p < 0.05). Grazing treatments (GR and GR+S) presented higher proportion of anterior-rib and lower proportion of breast in relation to indoor lambs (DRL−GRE and DRL). The feeding system did not affect the proportion of first category of commercial meat. It was concluded that light lamb carcass characteristics were slightly affected by the feeding systems, being carcasses from grazing lambs classified within the normal ranges for Ternasco commercial category, similarly to drylot systems. The small differences among the products of different feeding systems had no commercial constraint in the light lamb meat market. [Copyright &y& Elsevier]

Abstract: Nutrient intake, diet digestibility, N balance, carcass characteristics, and meat quality were evaluated in Awassi lambs fed different levels of sesame meal (SM). Twenty-seven Awassi lambs of similar weight (BW=18.8±0.74kg) and age (65±1.09 days) were equally divided into three treatments and fed individually high concentrate diets for 60 days. Group one served as a control and did not receive SM (SM0). Group two (SM8) and three (SM16) received 8 and 16% SM, respectively. Intakes of dry matter (DM), organic matter (OM), and crude protein (CP) were highest (P <0.05) for the lambs fed the SM8 followed by the SM0 and SM16 diets, respectively. Whereas, intake of ether extracts (EE) was greater for SM16 followed by the SM8 and SM0. Intake of metabolizable energy (ME) was greater (P <0.05) for SM8 than SM0 and SM16 treatments. Final weight and average daily gain (ADG) were greater (P <0.05) for SM8 than for both the SM0 and SM16 diets. All groups had similar feed conversion ratio; nevertheless production cost was lower (P <0.05) for SM8 and SM16 compared to SM0 diet. Digestibility of DM, OM, CP, and EE and N retention were similar among all treatment diets. Fasting live weight was greater (P <0.05) for lambs fed SM8 diet than for lambs fed SM0 and SM16 diets. Dressing percentage was greater (P <0.05) for SM0 diet when compared to SM8 and SM16 diets. Lungs and trachea weights were higher (P <0.05) in lambs fed SM8 diet than SM0 and SM16 diets. Loin weight was greater (P <0.05) in lambs fed SM8 diet compared to SM0 and SM16 diets. Lambs receiving the SM8 and SM16 diets had greater (P <0.05) total percentage in loin than the SM0 diet. No differences were observed in carcass and longissimus muscle linear dimensions, fat measurements, and meat quality characteristics among the treatment diets. It is concluded that sesame meal could replace 8% of soybean meal in the diet without any detrimental effect on lamb growth and meat quality, thus reduces feeding cost. [Copyright &y& Elsevier]

Abstract: The objective of this study was to investigate the effects of wheat straw level on growth performance and carcass parameter of lambs fed high concentrate diets. Thirty-six Awassi lambs (17.9±1kg) were randomly assigned to four experimental high concentrate diets with various wheat straw levels in a completely randomized design for 58 days. The experimental diets were isonitrogenous (16% CP) and contained 0, 5, 10 and 15% wheat straw. Results gained indicated that intake of dry matter; crude protein and metabolizable energy of the high wheat straw diets (10 and 15%) were similar (P >0.05) and significantly higher (P <0.05) than low wheat straw diets (0 and 5%). Final body weight, total weight gain, daily weight gain and feed efficiency of the high wheat straw diets were significantly (P <0.05) better than low wheat straw diets. Furthermore, the carcass parameters of the high wheat straw diets were significantly (P <0.05) superior to low wheat straw diets. In conclusion therefore, it may be recommended that high concentrate diets for Awassi lambs should contain at least 10% wheat straw for good growth performance and carcass quality. [Copyright &y& Elsevier]

Abstract: The effect of sex and rearing system on growth and carcass and meat characteristics of milk fed Assaf lambs was studied. Thirty-six lambs, 18 males and 18 females were used. Twelve lambs remained with their mothers throughout the experiment (NR). Within 24–36h of birth, the rest were housed individually and fed twice a day ad libitum (AAR) or at 70% of ad libitum consumption (RAR) with reconstituted cow’s milk. Sex did not affect animal performance, yet females showed higher carcass and non-carcass fat deposits. NR lambs showed greater BWG than AAR fed lambs, and AAR, higher than the RAR. Differences between naturally and artificially reared lambs in CCW and killing out percentage were not significant. Empty digestive tract and mesenteric fat weights were greater for RAR than NR lambs, with the AAR lambs demonstrating intermediate values; conversely, omental fat was greater in NR lambs. Carcass ether extract content was greater for NR lambs, possibly due to the greater growth. Use of ad libitum cow’s milk substitute in suckling lambs twice a day resulted in less body weight gain but similar killing out percentages compared to naturally raised lambs. A 70% restricted supply increased the days in suckling and reduced carcass fatness and compactness. Except for water loss, which was less in NR than artificially fed lambs, no differences were found in meat characteristics. [Copyright &y& Elsevier]

Abstract: The ARR allele of the prion protein gene is associated with resistance to classical scrapie, while the ARQ allele is associated with susceptibility. The objective of this study was to estimate the effect, on lamb growth and carcass traits, of replacing an ARQ allele with an ARR allele. Pedigree rams (22 Suffolks, 18 Texels and 18 Charollais) were sourced in pairs, from the same flock (by the same sire where possible), with one member being ARR/ARR and the other being ARQ/ARQ and these rams were progeny tested through single-sire mating in six flocks. Effects of ram genotype on reproductive performance of ewes and on growth and carcass traits of progeny were estimated using mixed model procedures with sire as a random effect. Ram genotype had no effect on litter size at birth or on lamb survival as measured by the number of lambs reared. The differences between the performance of progeny by ARR/ARR and ARQ/ARQ sires provided an estimate of the effect of substituting an ARR allele for an ARQ allele. This allele substitution had no effect on birth weight, growth rate, weight at 5 or 14 weeks, weight or ultrasonic fat depth at 120 days of age or on carcass classification traits (conformation, fatness) for the Suffolk, Texel or Charollais breeds. Substituting an ARR allele for an ARQ allele had a negative effect on ultrasonic muscle depth at 120 days for the progeny of Suffolk rams (P =0.01) but had a positive effect on ultrasonic muscle depth at 120 days for the progeny of Charollais rams (P =0.02). The ARR substitution effect was negative for slaughter age in the Suffolk (P <0.05) and positive for carcass weight in Texel progeny (P <0.05). The magnitude of these effects was quite small, however, and the overall results support the hypothesis that substituting an ARR allele for an ARQ allele has no important negative effect on lamb growth or carcass traits in any of the breeds examined. [Copyright &y& Elsevier]

Carcass composition and meat quality attributes of 55 suckling kids (27 males and 28 females) and 57 suckling lambs (28 males and 29 females) of Portuguese native breeds were investigated. These suckling kid and lamb meats are European meat quality labels produced according to "Cabrito de Barroso-PGI" and "Borrego Terrincho-PDO" specifications, respectively. Female kids were slaughtered at 9.1 ± 0.36 kg of BW, and male kids were slaughtered at 10.4 ± 0.37 kg of BW, corresponding to 20.1 and 17.7% of maturity, respectively. Female lambs were slaughtered at 8.6 ± 0.53 kg of BW, and male lambs were slaughtered at 9.9 ± 0.23 kg of BW, corresponding to 19.9 and 17.1% of maturity, respectively. At 24 h postmortem, various yield and quality measurements were collected. The left sides of the carcasses were dissected into muscle, subcutaneous fat, intermuscular fat, and bone. Final pH, instrumental color (L*, a*, b*), carcass measurements, and kidney knob and pelvic fat were also determined. Samples of LM were taken from the lumbar and thoracic cuts for intramuscular and meat quality determinations. At 72 h postmortem, a sample of LM was used for cooking losses and Warner-Bratzler shear force determination. Suckling lambs had greater dressing proportion than suckling kids (P < 0.01). Carcass fatness was not affected by species (P> 0.05), but females had greater kidney knob and pelvic fat proportion than males (P < 0.01). Lambs had greater proportions of the highly valued leg cut and lower proportions of shoulder, anterior rib, and neck cuts than kids. Dis-section results indicated that kid carcasses had greater muscle content and lower dissected fat and bone than lambs. Kids had greater (P < 0.001) muscle ultimate pH value than lambs (5.8 ± 0.02 vs. 5.6 ± 0.02). Males had greater (P < 0.05) muscle ultimate pH value than females (5.7 ± 0.02 vs. 5.6 ± 0.02). The kid meat was significantly lighter (P < 0.05) and less yellow (P < 0.001) than the lamb meat. Kids presented less cooking losses (P < 0.001) than lambs, and shear force value was significantly greater (P < 0.01) in lamb meat. The kid meat had significantly more moisture (P < 0.001) and less intramuscular fat content (P < 0.001) than lambs. At this maturity stage, there were significant differences on both carcass and meat quality attributes of suckling kids and lambs, possibly due to inherent differences between species. [ABSTRACT FROM AUTHOR]

In the present study 48 Suffolk × Mule (S × M) and 48 Scottish Blackface (SBF) weather lambs were used in a 2 breeds × 2 diets × 4 replications factorial experiment with 6 lambs per pen. Lambs were offered either a concentrate (CONC) finishing diet (DM: 876 g kg-1, estimated ME: 10.9 MJ kg-1 of DM, estimated DUP: 32.4 g kg-1 of DM) ad libitum, together with 100 g hay head-1 day-1, or silage (SIL) offered ad libitum (D value: 67.2), together with up to 450 g head-1 day-1 of a concentrate supplement (DM: 888 g kg-1, estimated ME: 10.9 MJ kg-1 of DM, estimated DUP: 63.9 g kg-1 of DM). Lambs were slaughtered at estimated MLC fat class 2 to 3L. Both breed and diet had a significant effect on daily live weight gain (DLWG) (S × M: 282 vs. SBF: 210 g; CONC: 383 vs. SIL: 109 g) and the food conversion ratio (FCR) was significantly affected by diet (CONC: 5.3 vs. SIL: 7.7). Breed × diet interactions were significant for both DLWG and FCR. Conformation score was better in the S × M lambs than in the SBF lambs (3.2 vs. 2.6; scale E = 5, P = 1), whereas diet influenced the estimated subcutaneous fat proportion (CONC: 121.5 g kg-1 vs. SIL: 113.2 g kg-1). [ABSTRACT FROM AUTHOR]

Abstract: Studies were conducted to determine the effects of supplementation upon intake, growth and carcass traits of Ovin Martinik hair sheep. Forty lambs weighing 20±3.7kg live weight (LW) were reared after weaning in individual pens during a 4-month experimental study. Four supplement levels were compared (10 lambs per treatment): the L0 group received the basal diet (tropical forage 0.75 UFL and 73PDINgkg−1 DM, INRA system) without concentrate, the L150, L300 and L600 groups were offered in addition 150, 300 and 600gday−1 of concentrate (1.15UFL and 151PDINgkg−1 DM), respectively. Intake (5 days a week) and growth patterns (every fortnight) were measured on the 40 lambs, while digestibility measurements (five times throughout the experimental period) were determined on half of the animals fitted with faecal bags and which were slaughtered according to the standard procedure at 33–35kg live weight for assessment of carcass traits and meat quality. The total dry matter intake (DMI) and digestibility increased (P <0.01) with the inclusion ratio of the concentrate in the diet: 82gDMkgW−0.75 vs. 97gDMkgW−0.75 and 65% vs. 73% between the two extreme groups, whereas forage DMI decreased and the forage substitution ratio was calculated to be 0.65. Growth and feed/gain ratios significantly (P <0.01) improved among the groups L0, L150 and L300, from an average of 134–188gday−1 and 7.0–5.7, respectively. The differences observed between L300 and L600 were not significant. Carcass weight and dressing out percentages significantly (P <0.01) increased with the addition of concentrate to the ration: from 13.1 to 15.6kg and from 39 to 46%, from L0 to L600, respectively. Consequently, the weights of the different cuts of the carcass varied. There was a significant effect of the supplementation level on the accumulation of internal fat tissues: the kidney fat weight increased from 107 to 237g from the L0 to the L600 groups. No significant effect was observed on the carcass quality scores, the ultimate pH and the colour parameters of the meat. By increasing the nutritional density of the diet, it was possible to obtain well-conformed and heavier carcasses, with no apparent detrimental effect on the quality. The optimal supplement supply with good quality grass would be 300gday−1 in our conditions. [Copyright &y& Elsevier]

Genetic parameters for eating quality assessed by trained taste panellists were estimated on longissimus thoracis et lumborum (LTL) muscle in Scottish Blackface lambs, comprising lines previously divergently selected for carcass lean content (FAT and LEAN lines) as well as crosses between these lines. Also, relationships between eating quality assessments and fatty acid composition were investigated. Eating quality and fatty acid phenotypic measurements were made on 350 male lambs, at ca. 8 months of age. Eating quality measurements included 18 descriptive terms and fatty acid composition measurements included in total 17 fatty acids of three types: saturated, monounsaturated and polyunsaturated. The FAT line had juicier meat and more vegetable flavour than the LEAN line. Most of the eating quality traits were moderately to highly heritable, with heritabilities ranging from 0.21 (lamb flavour) to 0.92 (sweet flavour). Lamb flavour, juiciness and overall liking were strongly negatively correlated with individual polyunsaturated fatty acids, with the correlations being significantly different from zero. Overall liking was strongly positively correlated with the proportion of total monounsaturated fatty acids. This study provides new information on genetic parameters for eating quality traits in sheep, which may lead to novel opportunities for genetically improving these traits. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this research was to estimate the effects of grading up of Gentile di Puglia with Ile de France on carcass traits and the composition of cuts in lambs slaughtered at 35 and 54 days of age. Data was collected on 223 lambs of both sexes, single birth, belonging to the genetic types Ile de France (IF), Gentile di Puglia (GP) and the result of grading up of the latter with Ile de France rams (F1 and F2). About half of the subjects were fed with maternal milk (natural feeding) while the others were fed on a milk replacer (artificial feeding). The lambs of both groups were randomly allocated in two slaughter age subgroups: 35 and 56 days. The results of statistical analysis showed that the considered factors of variation significantly influences the weight of the carcass, the percentage of cuts and their composition. Most of the variation was due to the age and to the feeding system. The F2 lambs on average had the heaviest carcass and sides, the GP had the highest percentage of fore quarter while the IF had the highest percentage of back quarter. Furthermore F1 lambs did not show any heterotic effect compared with both parental breeds, while F2 breeds showed better performance. The carcass of the males resulted heavier than the females, with a lower percentage of dissectible fat at the neck, brisket, shoulder and leg and a higher percentage of meat in the shoulder cut. The lambs slaughtered at 35 days of age showed a higher incidence of kidney, shoulder and leg weight, while at 56 days furnished a higher percentage of kidney fat, brisket and loin weight. The artificially fed lambs furnished a lighter carcass and neck and shoulder cuts than naturally fed lambs, less kidney fat and a higher percentage of kidney, rib and loin weight. The employment of artificial feeding permitted a higher percentage of lean and less dissectible fat as well as a higher lean/bone ratio. These results show that Ile de France rams crossbreed with Gentile di Puglia determine good productive performance if the lambs derive from the F2 crossbreed and are artificially fed and slaughtered at 56 days of age. [Copyright &y& Elsevier]

Lambs weight of first treatment increased significantly in comparison with other treatments lambs. This increase started from the day 30 till the end of the study. Group two obtained significant increase in dressing percentage, slaughter residuals, cuts weight except the tail and bone and fat percentages. Weights of liver and heart of the third treatment lambs significantly greater than that of groups. However, animals of third treatment got significantly lower kidney weight .Fat deposition was varied due to different treatment. Animals of treatment one, two and three deposit significantly more fat around heart , rumen, intestine and kidneys . Animals of third and fourth treatments recorded lower carcass length and leg width. Animals belong to treatment four showed lowest performance for all studied traits. The results also revealed a significant increase in WBC count of treatment four and PCV and Hb of group three at the 90 day . [ABSTRACT FROM AUTHOR]

This research was carried out to determine the effects of shearing of different genotypes of male lambs (one from pure Karayaka stock and two from its crossbreed) in winter on bodyweight gain, feed consumtion, feed conversion efficiency, rectal temperature and carcass yield. A total of 21 lambs aged 8 months were allocated randomly to experimental groups according to a 2 × 3 factorial arrangement for shorn and unshorn animals. The lambs were fed grass hay (100 g/lamb/day) and commercial concentrate feed ad libitum during a 54-day of fattening period. The lambs were shorn in the middle of the experiment (27 days after beginning the trial). The interaction between the shearing treatment × genotype of the studied parameters was found to be insignificant. The shearing process increased the rectal temperature ( P < 0.01), hot carcass yield ( P < 0.05) and dressing percentage ( P < 0.05) and decreased the weight of the edible inner organs ( P < 0.01). Some of these parameters were affected by the genotypes. It was concluded that shearing male lambs in the winter can have a beneficial effect on the hot carcass weight and dressing percentage without affecting fattening performance, and the performance of Karayaka lambs and its crossbred male lambs were similar under the conditions of the present study. [ABSTRACT FROM AUTHOR]

The performance of two fat-tailed sheep breeds, Chaal and Zandi, and their F1 and R1 crossbred lambs from a lean-tailed breed, Zel, was compared. The weaned lambs from the Chaal and Zandi groups were finished over periods of 105 and 90 days, respectively, and body weight gain and feed consumption were recorded. Forty six male and female lambs from the six finishing groups were slaughtered. The weights of blood, internal organs, intestines before and after removal of digesta, head, feet, pelt and carcasses were recorded. The left sides of the carcasses were cut into six pieces. Individual joints were dissected into lean meat, bone, subcutaneous fat (SCF), intramuscular fat (IMF) and trimmings, and weighed separately. The fat surrounding the intestine and kidney was weighed and considered as internal fat. All the soft tissue (lean meat and fat) of the left sides of the carcasses was ground and representative samples were taken for chemical analyses. The differences of eye muscle (Longissimus dorsi) area (cm²), and protein and bone percentages were not significant between both breeds and their crosses. In the R1 the fat-tail percentage was less than in the F1 and pure lambs of both breeds. In contrast, the SCF and IMF percentages were higher in all crossbred combinations. The internal fat percentages in crossbreds were higher, and in the Chaal group differed significantly from that of the pure lambs. The SCF/IMF ratio in the R1 lambs was lower than in the pure breds. This difference for Chaal crossbreds was significant. The lower ratio of SCF/IMF and the higher internal fat of crossbred lambs compared to pure breds showed that carcass quality of the crossbred was inferior compared to the pure bred lambs in terms of fat distribution in the body. [ABSTRACT FROM AUTHOR]