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Intensive finishing on pasture is already accepted as a good nutritional management strategy due to the capacity of enhancing performance without requiring physical confinement infrastructure; however, it is not yet known whether early weaning has beneficial results in this system. The effect of different ages at weaning – 42, 56 and 84 days – on the performance, carcase traits and bioeconomicity of Santa Inês lambs intensively finished on Massai grass pasture (Panicum maximum cv. Massai) was evaluated. Fifty-seven lambs were weekly weighed from birth until they reached 30 kg of body weight, when the males (not castrated) were slaughtered and the females incorporated into the herd. It was found that weaning at 42 or 56 days depressed lamb performance, so that animals weaned at 84 days reached slaughter weight 32 days earlier. There was no effect (P > 0.05) on carcase traits and meat cuts, but animals weaned at 84 days were more economically profitable. Weaning Santa Inês sheep at 84 days that will be intensively finished in Massai pasture enhances performance and brings earlier age at slaughter, in addition to positively impacting the economic viability of the production system. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the influence of age at slaughter on various carcass characteristics of Hassan sheep. A total of 36 male Hassan sheep 12 each in 3 different age groups, viz., 6-8 months (T1), 12-15 months (T2) and 30-32 months (T3) were slaughtered as per standard procedure. The pre-slaughter weight (PSW), hot carcass weight (HCW), dressing percent (DP) and loin eye area (LEA) revealed a significant difference (p<0.05) between the three age groups. Age group T3 recorded the highest PSW and HCW, whereas T2 recorded the highest DP (49.74%) and LEA (12.68 cm2). The age at slaughter was found to have a significant (p<0.05) effect on the weight of the non-carcass components and the offal weights. Group T3 recorded a significantly higher (p<0.05) weight of liver, head, feet, blood, heart, kidney, spleen, brain followed by T2 and T1. It was evident that in T3 group the per cent of major primal cuts, viz., shoulder, leg and loin cuts decreased significantly (p<0.05), whereas there was an increase in per cent of neck and rack cuts clearly indicating that in older/ aged animals the per cent of valuable cuts decreased. No significant difference was observed in the linear carcass measurements with respect to T1 and T2, whereas T3 recorded significantly higher measurements as compared to T1 with respect to all the linear carcass measurements. Based on the results it is concluded that the optimal age of slaughter of Hassan sheep is 12-15 months to obtain better carcass yield and yields of valuable cuts with good muscling. [ABSTRACT FROM AUTHOR]

Context: In the belief that feed costs and use of cereal grains are reduced, production systems based on grazed and conserved forage in which cattle are slaughtered at 30 to 36 months of age are increasingly advocated. Aims: As there is a scarcity of information concerning meat quality traits of beef from such extended rearing systems, three finishing systems of different lengths (Short, 14–16 months; Medium, 20–24 months; Long, 31–34 months) were compared in which cattle were slaughtered at similar conformation and fat classification scores. Methods: The experiment comprised a three (system) × two (gender) design with 24 Limousin cross-bred cattle (12 steers and 12 heifers) assigned to each system. Characteristics of the rib section (between and inclusive of the 5th and 10th ribs) and sensory properties of M. longissimus thoracis samples were then assessed. Key results: Older (Long system) cattle had greater rib section and L. thoracis weights. L. thoracis was tougher in older (Long system) cattle when assessed by a trained sensory panel. Heifers had lower rib section weights than steers but neither rib section composition or meat toughness differed between genders. Gristle (visible connective tissue) in the rib section increased with system length and was associated with an increased perception of gristle on eating. Conclusions: Overall meat quality was considered commercially acceptable regardless of system. Implications: The likely increased greenhouse gas emissions but reduced utilisation of food resources from the Long system need to be considered in conjunction with the meat quality characteristics of the system. There is on-going debate over how the eating quality of beef is influenced by the age at which cattle are slaughtered. When the eating quality of beef derived from cattle ranging from 14 to 34 months in age was compared, overall, there were few differences due to age and beef was of satisfactory eating quality. However, the likely increased greenhouse gas emissions from the older cattle need to be considered when assessing beef quality characteristics. [ABSTRACT FROM AUTHOR]

Aim: To investigate factors influencing Campylobacter spp. colonization of broiler chickens. Methods and Results: Campylobacters were isolated from caeca from 319 flocks of two different breeds (199 Cobb and 120 Hubbard), reared as standard (199), Freedom Food/corn fed (57), free‐range (47) or organic (16). The standard category exclusively used Cobb birds slaughtered at 38‐41 days. The Freedom Food/corn‐fed and free‐range Hubbard birds were slaughtered at 49–56 days and the organic flocks at 70 days. Campylobacters were picked at random from direct plates. Both breed of chicken (Hubbard) and age at slaughter were independently associated with increased likelihood of colonization by Campylobacter coli rather than Campylobacter jejuni, but breed could not be separated from other aspects of husbandry with the data available. Conclusions: Chickens are frequently colonized by C. jejuni and C. coli and most human infections originate from poultry. In most developed countries approximately 90% of human infections are caused by C. jejuni, but fewer than 10% by C. coli. This might be due to C. coli being less pathogenic than C. jejuni to humans, and/or to chicken meat carrying fewer C. coli than C. jejuni. More investigations are needed into these aspects before it can be concluded that slaughtering older birds from slower‐growing breeds would reduce the risk of human Campylobacter disease. Significance and Impact of the Study: Meat from certain breeds of poultry are predominantly colonized by C. coli rather than C. jejuni. More research is needed to understand the impact this may have on the number and severity of human campylobacter infections. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effects of age at slaughter and sex on carcass characteristics and meat quality of Betong chickens that were raised under a semi-free-range system. A total of 360 chickens from Takbai, Narathiwat Province, Thailand were arranged into 3x2 factorial design with 3 levels of age at slaughter (16, 20, 24 weeks) and sex (male and female) in CRD. The experiment consisted of 6 treatments with 3 replications. Ten chickens of each replicate from each treatment group were randomly sampled for carcass yield and meat quality. Results showed that slaughter and carcass weights were significantly higher when the age at slaughter increased (P<0.01). Males had heavier slaughter and carcass weights (P<0.001) with lower breast percentage than the female chickens in each particular age. Higher yellowness value was significantly illustrated when the age of chickens increased. This color value was higher in both breast and thigh meat of the female chickens (P<0.05). Considering texture analysis, the males had significantly higher shear force value than the females (P<0.05). This shear value tended to increase when the age of the chicken increased (P>0.05). There was no significant difference observed between age at slaughter on chemical composition (P>0.05). Nevertheless, the males had less fat content in breast meat and higher collagen content in thigh meat than the female Betong chickens (P<0.05). The results show that males should be slaughtered at 20 weeks, while the females should be slaughtered when they reach the age of 24 weeks. [ABSTRACT FROM AUTHOR]

Two production systems and several ages at slaughter were used: 12, 14 and 16 months for outdoor rearing (with the final finishing phase in the Montanera system, in which fed was based on natural resources, mainly acorns and grass) and 8, 10 and 12 months for animals reared indoors (intensive system: with feed based on commercial fodder) to evaluate their effect on the muscle fibre population and size of the Longissimus thoracis, (LT) muscle, as well as fresh loin quality traits. Animals that were older at slaughter revealed increased fibre sizes of the LT muscles in the pigs reared in the Montanera system. The LT muscles of the animals reared in intensive systems had a lower percentage of type I fibres and higher size of type IIB than those reared in the Montanera system. The approximate composition and instrumental colour of Montanera fresh loins were affected by the animal slaughter age. In the case of the intensive system, the effect of animal slaughter age had an impact on the approximate composition, instrumental colour, water loss and textural properties. Therefore, different ages at slaughter of Iberian pigs showed variations in some quality parameters in the fresh loins in both the Montanera and Intensive systems, thus proving to be a factor of variability and homogeneity of the Iberian products. The meat from Iberian pigs reared in an intensive system and slaughtered at a younger age proved to be more tender. The production system affected all the above quality traits, with the exception of water loss.

Comparison of alternative dairy (cross-)breeding programs requires full appraisals of all revenues and costs, including beef merit. Few studies exist on carcass characteristics of crossbred dairy progeny originating from dairy herds as well as their dams. The objective of the present study was to quantify, using a national database, the carcass characteristics of young animals and cows differing in their fraction of Jersey. The data set consisted of 117,593 young animals and 42,799 cows. The associations between a combination of sire and dam breed proportion (just animal breed proportion when the dependent variable was on cows) with age at slaughter (just for young animals), carcass weight, conformation, fat score, price per kilogram, and total carcass value were estimated using mixed models that accounted for covariances among herdmates of the same sex slaughtered in close proximity in time; we also accounted for age at slaughter in young animals (which was substituted with carcass weight and carcass fat score when the dependent variable was age at slaughter), animal sex, parity of the cow or dam (where relevant), and temporal effects represented by a year-by-month 2-way interaction. For young animals, the heaviest of the dairy carcasses were from the mating of a Holstein- Friesian dam and a Holstein-Friesian sire (323.34 kg), whereas the lightest carcasses were from the mating of a purebred Jersey dam to a purebred Jersey sire which were 46.31 kg lighter (standard error of the difference = 1.21 kg). The young animal carcass weight of an F1 Holstein-Friesian × Jersey cross was 20.4 to 27.0 kg less than that of a purebred Holstein-Friesian animal. The carcass conformation of a Holstein-Friesian young animal was 26% superior to that of a purebred Jersey, translating to a difference of 0.78 conformation units on a scale of 1 to 15. Purebred Holstein-Friesians produced carcasses with less fat than their purebred Jersey counterparts. The difference in carcass price per kilogram among the alternative sire-dam breed combinations investigated was minimal, although large differences existed among the different breed types for overall carcass value; the carcass value of a Holstein-Friesian animal was 20% greater than that of a Jersey animal. Purebred Jersey animals required, on average, 21 d longer to reach a given carcass weight and fat score relative to a purebred Holstein-Friesian. The difference in age at slaughter between a purebred Holstein-Friesian animal and the mating between a Holstein-Friesian sire with a Jersey dam, and vice versa, was between 7.0 and 8.9 d. A 75.8-kg difference in carcass weight existed between the carcass of a purebred Jersey cow and that of a Holstein- Friesian cow; a 50% Holstein-Friesian-50% Jersey cow had a carcass 42.0 kg lighter than that of a purebred Holstein-Friesian cow. Carcass conformation was superior in purebred Holstein-Friesian compared with purebred Jersey cows. Results from this study represent useful input parameters to populate simulation models of alternative breeding programs on dairy farms, and to help beef farmers evaluate the cost-benefit of rearing, for slaughter, animals differing in Jersey fraction. [ABSTRACT FROM AUTHOR]

Meat from the Greater rhea (Rhea americana) could compete with traditional red meats, diversifying the market of protein products of animal origin. The meat from 32 rheas was used to study quality aspects and this included ultimate pH (pHu), color, water-holding capacity (WHC%), cooking loss (CL%) and tenderness. The muscles sampled were the Gastrocnemius pars externa, Iliofibularis and Obturatorius medialis from both sexes at multiple ages (10, 12, 14, 16 months). Age at slaughter affected WHC%, CL%, and color in raw meat and tenderness in cooked meat. Muscles under study showed differences in terms of pHu, raw meat color, and tenderness of cooked meat. Sex did not have a significant effect on any of the variables studied. According to our results, rhea meat from younger animals, between 10 to 14 months old, was tender and moderately juicy and the visual color was appreciated by the consumers. [ABSTRACT FROM AUTHOR]

The modern consumer of sheep meat requires uninterrupted market supply with qualitatively standardized meat, without excess fat and with high tenderness, which has encouraged producers to slaughter young sheep. A lamb’s diet during the pre-weaning phase was discussed in this review because it is of great importance for achieving success in a meat production system, given the high speed of lambs’ growth during their first weeks of life. Supplying palatable concentrate in creep-feeders from the first days of life promotes pre-stomach development and adapts the animal to a solid diet consumption; important processes for enhancing animal performance, since nutritional requirements, especially for energy, are high during this period and can only be met by milk for a short time. An early weaning technique can be adopted from 35 days old, when adequate nutritional support is provided. Unweaned lamb slaughtering combined with creep feeding and controlled feeding have superior effects to early abrupt weaning, probably by avoiding the adverse effects generated by post-weaning stress. The use of a milk replacer is seldom reported due to the difficulty in finding specific products for sheep and its high cost. Controlled suckling does not affect the performance of lambs. Further studies investigating lamb feeding strategies need to be developed during the pre-weaning period.

The objective of the study was to determine the effects of animal related factors on bruising in slaughter cattle, creatine kinase (CK) and beef quality. Three hundred and twenty one cattle from three breeds (108 Bonsmara, 130 Beefmaster and 83 Brahman) were used in this study. The animals were grouped as follows: Group 1 (16 months old), Group 2 (18 months old) and Group 3 (24 months old). At exsanguinations, blood samples for CK determination were collected using disposable vacutainer tubes. Muscularis longissimus thoracis et lumborum (LTL) was collected 24 h after slaughter to determine the colour (L*, a*, and b*) and ultimate pH (pHu) of beef. Breed, sex and age had significant effects (p

Forty male lambs of the mountain Greek breed were used to evaluate the effect of age at slaughter on carcass characteristics and composition. The slaughter of lambs was carried out at the age of 30, 45, 60, 75 and 90 days. The slaughter procedure, carcass dissection and carcass composition were realized according to the standard method of CIHEAM-AGRIMED programme. The results of this work showed that the lambs of different age groups did not differ in dressing percentage significantly. The proportion of muscles showed a tendency of increase with the increasing slaughter age but the differences were not significant. The proportion of total fat in carcass increased with the increasing slaughter age from 20.84 to 23.59% for the age group of 30 and 90 days, respectively (P < 0.05). On the contrary, as the age at slaughter increased, the proportion of bones decreased (P < 0.05). Subcutaneous, intermuscular, perinephric and pelvic fats increased with the slaughter age, but only the subcutaneous fat was influenced significantly (P < 0.05). Among the different commercial cuts proportions of long leg, first 5 ribs and shoulder decreased, while those of last 8 ribs-loin and breast-flank increased (P < 0.05). The overall results suggest that the slaughter age of lambs of the mountain Greek breed should be increased from the present ~45 days to more advanced age of 75 or 90 days in order to improve the farmers' profits without serious negative effects on the quality of carcasses or meat of lambs.

Foram utilizados 40 bovinos nelores, divididos em dois grupos: SUP - os animais foram mantidos a pasto e receberam 0,5% do peso vivo em suplemento no período da seca; NSU - animais mantidos a pasto, sem suplemento. Metade dos animais de cada tratamento eram castrados e a outra metade eram inteiros. Observou-se melhor ganho médio diáriodurante o período do inverno para os animais suplementados (SUP = 0,339; NSU = 0,193 kg) e os animais pertencentes ao grupo controle (NSU) apresentaram ganho compensatório no período do verão. Os animais inteiros obtiveram ganhos médios diários superiores aoscastrados durante todo o período (0,506 x 0,412 kg) e atingiram o peso de abate (480 kg) a uma idade mais jovem (330 x 409 dias até o abate). Verificou-se melhor rendimento de carcaça fria para os animais castrados. A suplementação não promoveu melhorescaracterísticas de carcaça aos animais testados.Forty Nellore bovines were used. Animals were divided in two groups: 1) SUP – Animals on pasture and supplemented (0.5% of live bodyweight) with a concentrated during the winter (dry season), and 2) NSU – Animals on pasture, without supplementation. Half of the animals of each treatment was steers and the other half was bulls. Best average daily gain (ADG) during the period of the winter was observed in the supplemented animals (SUP = 0.339; NSU = 0.193 kg), and the animals belonging to the control group (NSU) presented compensatory weight gain in the period of the summer. Bulls had greater ADG during the whole period than steers (0.506 vs. 0.412 kg), and they reached the slaughter weight (480 kg) at a younger age (330 vs. 409 days up to slanghter). Best cold carcass dressing percentage was verified for steers and the supplementation did not promotebetter carcass characteristics in the tested animals.

Foram utilizados neste experimento 31 cordeiros cruzados Hampshire Down, Ile de France e Suffolk, distribuídos em quatro tratamentos: inteiros ou castrados com burdizzo, borracha ou faca. A castração ocorreu aos 58 dias de idade. Após o desmame, aos 84 dias, os animais foram confinados até atingirem o peso vivo de 30 a 32 kg, quando abatidos. Não houve diferença significativa entre os tratamentos e entre os grupos genéticos para os pesos ao nascimento, desmame e abate, para o ganho de peso médio diário do nascimento ao abate e para a idade ao abate. As médias para os ganhos de peso foram 0,179; 0,177; 0,170 e 0,147 kg e para a idade ao abate de 152,0; 156,0; 161,5 e 188,9 dias para os cordeiros inteiros, castrados com burdizzo, com borracha e com faca, respectivamente. Os cordeiros Hampshire Down, Ile de France e Suffolk ganharam, respectivamente, 0,176; 0,163 e 0,166 kg diariamente. Os animais inteiros apresentaram menores rendimentos verdadeiros de carcaça quente ou fria; não havendo outras diferenças importantes entre os tratamentos para as demais características de carcaça estudadas. Os cordeiros Hampshire Down apresentaram maiores rendimentos de carcaça fria, enquanto os Suffolk tiveram menores rendimentos verdadeiros de carcaça e menor percentagem de pescoço, e os Ile de France apresentaram as carcaças mais curtas. O peso ao nascimento teve efeito significativo sobre o ganho de peso e a idade ao abate dos cordeiros. Os resultados mostraram não haver diferenças no desempenho de cordeiros inteiros ou castrados por diferentes métodos abatidos entre 30 e 32 kg de peso vivo, e que pode ocorrer diferenças entre animais de diferentes grupos genéticos quando abatidos com peso semelhante.Thirty-one Hampshire Down, Ile de France and Suffolk crossbred lambs divided into four treatments: intact, castrated with burdizzo, with rubber bands and with knife, were used in this experiment. Castration occurred at 58 days of age. After weaning, at 84 days, the animals were fed lot until 30 to 32 kg of live weight, and then slaughtered. There were no significant differences among treatments and genetic groups for birth, weaning and slaughter weights, for average daily gain from birth to slaughter, and for age at slaughter. The average daily weight gain from birth to slaughter were 0.179, 0.177, 0.170 and 0.147 kg, and the age at slaughter were 152.2, 156.0, 161.5 and 188.9 days, respectively, for intact, castrated with burdizzo, with rubber bands and with knife lambs. Hampshire Down, Ile de France and Suffolk had 0.176; 0.163 and 0.166 kg of average daily weight gain, respectively. Intact lambs presented lower carcass true yields; there were no other important differences among treatments for the studied traits. Hampshire Down lambs presented greater cold carcass yields, while Suffolk had lower carcass true yields and lower neck percentage, and the Ile de France showed the shortest carcasses. Birth weight had significant effects on lamb weight gains and age at slaughter. The results suggest no significant differences on the performance of intact and castrated by different methods lambs slaughtered between 30 to 32 kg, and that meat lambs from different genetic groups can present significant differences when slaughter at same weight.

The objective of the study was to determine the effects of animal related factors on bruising in slaughter cattle, creatine kinase (CK) and beef quality. Three hundred and twenty one cattle from three breeds (108 Bonsmara, 130 Beefmaster and 83 Brahman) were used in this study. The animals were grouped as follows: Group 1 (16 months old), Group 2 (18 months old) and Group 3 (24 months old). At exsanguinations, blood samples for CK determination were collected using disposable vacutainer tubes. Muscularis longissimus thoracis et lumborum (LTL) was collected 24 h after slaughter to determine the colour (L*, a*, and b*) and ultimate pH (pHu) of beef. Breed, sex and age had significant effects (p<0.05) on bruising score, CK levels and beef quality. Bonsmara breed had the highest (80%) bruising score percentage, CK (705.3±80.57 U/L) and pHu (6.3±0.05) values while the Bonsmara had the highest L* (24.8±0.78) a* (17.5±0.53) and b* (12.8±0.53) values. Higher CK levels were also observed in winter compared to summer, spring and autumn respectively. Therefore, animal factors (sex, breed and animal age at slaughter) contribute to the development of bruises and have an effect on the levels of CK and meat quality. It was also concluded that there is no significant relationship between meat parameters (L,* a*, and b*) and CK levels. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate the heritability and genetic correlation of age at slaughter (AS), as an indicator of slaughter precocity, carcass weight (CW), and CW gain (CWG = CW x AS-1) obtained from young bulls of 3 Italian autochthonous beef cattle breeds [i.e., Chianina (CHI), Marchigiana (MAR), and Romagnola (ROM)]. In addition, the study aimed at evaluating the effect of corrected or uncorrected CW for AS, and analyzing the relationship between adjusted or unadjusted CW with CWG in term of changes in rank correlation in groups of sires with high accuracy. Data were obtained from the Consortium of protected geographical indication (PGI) "Vitellone Bianco dell'Appennino Centrale" (i.e., white young bull of Central Apennines), approved by the European Union. After editing, 20,872 complete records were retained for subsequent Bayesian analysis. Univariate animal model produced h² estimates of medium value for AS (i.e., from 0.28 for CHI to 0.39 for the ROM breed). The CW presented h² estimates less than AS, ranging from 0.13 for CHI to 0.24 for ROM bulls. The adjustment of CW by AS (CWU-AS) increased the h² values for CW in all breeds (i.e., from 0.20 to 0.29). Point estimate of genetic correlations between AS and CW obtained by a bivariate analysis were moderate to low, and negative in all breeds (from -0.08 to -0.29). Rerankings of sire for univariate CW (CWU) analysis and CWU-AS were more noticeable for CHI and ROM (rank correlation of 0.875 and 0.897, respectively) than for the MAR breed (rank correlation of 0.967). Comparing bivariate EBV for CW with EBV for CWU or CWU-AS increased rank correlation to 0.937 for ROM, but for CHI it remained lower (i.e., 0.861), indicating a possible large reranking of sires by correcting CW for AS in this breed. Daily CWG presented h² estimates greater than CW and similar or greater than AS. It appears to be a good indicator of instant growth rate capacity of the animal but lacking information on the endpoint of fattening in terms of age and weight. Field slaughter data for the CHI, MAR, and ROM breeds under the PGI labeling indicate that AS is not a mere environmental factor to be corrected for but trait subjected to genetic control. Because of its economic relevance in fattening, age at slaughter, as an indicator of slaughter precocity, could become a trait requiring careful consideration for selection of beef breeds. [ABSTRACT FROM AUTHOR]

The article presents a preliminary comparative analysis of the archaeozoological data from two Neolithic sites in the plain of Ararat in Armenia. It notes that the studies on fauna reveal many similarities in the comparison of the results. It also notes that the contribution of hunting is limited while fishing was practiced very little.

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]

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]

Abstract: Seasonal availability of lamb in the Western United States contributes to a large fluctuation in lamb supply. However, alternatives to fall marketing may not be practical unless feedlot performance and carcass characteristics of older lambs finished in the spring is equal to or superior to fall finished lambs. Our objective was to evaluate feedlot performance and carcass characteristics of spring-born wether lambs that were either feedlot finished in the fall and slaughtered at 7–8 months of age, or feedlot finished in the spring and slaughtered at 14–15 months of age. April- and May-born whiteface wethers (n =240) were used in a complete random design experiment with wethers finished on an 80% whole barley-based diet starting when they were either 5–6 months (FALL), or 12–13 months (SPRING) of age in October or May, respectively. Wethers were fed in outdoor pens with 12-pens/finishing trial, four lambs/pen, and six finishing trials (three fall and three spring) during a 3-year period. Feedlot response variables included BW, DMi, gain:feed ratios, ADG, and body composition. Carcass variables were body wall thickness, back fat, yield, and USDA quality grade. Year×treatment interactions were detected for all feedlot variables (P <0.05), but not for carcass characteristics (P >0.50). Intake, ADG, final BW (years 2 and 3 only), and body wall thickness were greater (P <0.05) for SPRING than FALL wethers. Quality grade, yield, and fat thickness depth did not differ (P >0.05) between FALL and SPRING finished lambs. Gain:feed ratio did not differ (P >0.05) between FALL and SPRING wethers in year 1, but was greater (P <0.05) for SPRING wethers in year 2, and lower (P <0.05) for SPRING wethers in year 3. We concluded that older wethers finished on a barley diet and managed under conditions of our study perform better in the feedlot than younger lambs. Combining these results with previous work demonstrates that older lambs are similar in terms of tenderness and flavor as younger wethers, and older lambs finished in spring are a desirable commodity for the feedlot industry and the consumer. [Copyright &y& Elsevier]

Simple Summary: This paper is in attempt to assess the impact of the production system Montanera and intensive, and the age at slaughter in each of them, on the muscle fibres of Longissimus thoracis (LT) and meat quality of fresh loins from Iberian pigs. The age at slaughter affected the fibre size of Montanera LT muscles, while the production system influenced the fibre type I population and type IIB fibre size. The age at slaughter affected the fresh loin quality trait depending on the production system; Montanera and intensive fresh loins from older animals yielded higher myoglobin and redness values. Additionally, intensive fresh loins derived from older animals yielded the lowest intramuscular fat and the highest cook loss and shear force in the Warner-Braztler shear force test. These above-mentioned parameters differed due to production systems, Montanera fresh loins less fat-infiltrated and tough but with higher redness values. The results of the present study contribute to shedding light regarding how the production-related factor animal slaughter age may influence the muscle fibre population, size and quality traits of fresh meat. Two production systems and several ages at slaughter were used: 12, 14 and 16 months for outdoor rearing (with the final finishing phase in the Montanera system, in which fed was based on natural resources, mainly acorns and grass) and 8, 10 and 12 months for animals reared indoors (intensive system: with feed based on commercial fodder) to evaluate their effect on the muscle fibre population and size of the Longissimus thoracis, (LT) muscle, as well as fresh loin quality traits. Animals that were older at slaughter revealed increased fibre sizes of the LT muscles in the pigs reared in the Montanera system. The LT muscles of the animals reared in intensive systems had a lower percentage of type I fibres and higher size of type IIB than those reared in the Montanera system. The approximate composition and instrumental colour of Montanera fresh loins were affected by the animal slaughter age. In the case of the intensive system, the effect of animal slaughter age had an impact on the approximate composition, instrumental colour, water loss and textural properties. Therefore, different ages at slaughter of Iberian pigs showed variations in some quality parameters in the fresh loins in both the Montanera and Intensive systems, thus proving to be a factor of variability and homogeneity of the Iberian products. The meat from Iberian pigs reared in an intensive system and slaughtered at a younger age proved to be more tender. The production system affected all the above quality traits, with the exception of water loss. [ABSTRACT FROM AUTHOR]