Increasing Slaughter Weight Research Articles

An investigation of slaughter weight and muscle type effects on carcass fatty acid profiles and meat textural characteristics of young Holstein Friesian bulls

Study objectives included the assessment of carcass fatty acid composition and meat texture characteristics of younger Holstein Friesian bulls. Three experimental groups were formed based on the weights of the 23 young bulls at slaughter: lighter, medium, and heavier. Samples were taken from the Gluteus medius (GM) and Longissimus thoracis muscles 24 h after slaughter. Fatty acid composition, Warner-Bratzler Meat Shear (WBS) measurements, as well as textural profile analysis (TPA) and sensory analysis of the muscle samples were conducted. The fatty acid composition was determined using Thin Layer Chromatography (HPTLC). Polyunsaturated fatty acids and dietary fatty acids give a neutral hypocholesterolemic effect in direct fluorescent antibody (DFA) contents, DFA/OFA (C14:0+C16:0) ratio, hardness, Warner-Bratzler Shear force and also the chews number – which is desirable - before swallowing (NCBS) the meat were significantly decreased with the increasing slaughter weight. Higher slaughter weight resulted in a larger amount of beef with a better panel tenderness score; however, the meat obtained from the LSW group was less healthy considering the fatty acid profile. Additionally, internal fat contained the highest saturated fatty acids concentrations, while subcutaneous fat contained the highest amount of monounsaturated fatty acids. Furthermore, intramuscular fat levels were highest in PUFA and PUFA/SFA ratio. As a result, this study strongly suggests that slaughter weight and anatomical location of fat samples contribute significantly to meat texture characteristics and fatty acid profiles in Holstein Friesian bulls.

Killing indicators and quality of muscle tissue of pigs after administration of the drug “Kronocid-L” into the diet

The effect of feeding the drug “Kronocid-L” with the content of chelated compounds of microelements on slaughter performance and the quality of muscle tissue of pigs was investigated. Chelate compounds, or chelates (from the English chelate – claw), belong to complex compounds that are formed as a result of the connection of a cation (metal ion) with two or more atoms of a complexon (ligand) molecule. Chelates are significantly different from non-chelated compounds both in terms of chemical and physical properties and in their effects on living organisms. A scientific and economic experiment was conducted on two analogous groups of 75-day-old fattening young pigs, 12 heads in each, obtained from crossing sows of the large white breed with boars of the landrace breed. The control group of pigs consumed the basic diet during the equalization and baseline periods. In addition to the main diet, the experimental group was fed the drug “Kronocid-L” with the content of chelated compounds of microelements at the rate of 1 liter per 1 ton of water. The drug “Kronrocid-L” is a transparent green-blue solution that contains chelate compounds of trace elements (iron, zinc, manganese and copper), formic, acetic, orthophosphoric, lactic, citric, succinic and benzoic acids in an amount of 19 % by weight in an aqueous solution. It was established that feeding pigs on fattening with the above-mentioned preparation contributes to an increase in slaughter weight and slaughter yield in the 2nd experimental group, respectively, by 12.8 kg or by 15 % (P < 0.05) and 5.6 % (P < 0.05 ) against benchmarks. At the same time, under the influence of the feed additive, the thickness of the lard above the 6-7 thoracic vertebra decreased by 3.2 mm or by 10 % (P < 0.05) and the area of the “muscle eye” increased by 2.8 cm2 or 6 % P < 0.01). The use of the drug “Kronocid-L” makes it possible to improve the quality indicators of muscle tissue, namely, to increase the juiciness and intensity of meat color, to increase the content of protein and fat, which indicates an increase in the intensification of protein and fat metabolism.

Effects of Slaughter Weight and Muscle Types on Carcass and Meat Quality Characteristics of Holstein Friesian Bulls

The aim of this study was to determine the effects of slaughter weight and muscle types on carcass characteristics, chemical composition and meat quality characteristics of young Holstein Friesian bulls. For this purpose, the 21 young bulls were assigned to three experimental groups based on their weights at slaughter called lighter (LSW) (470.4±32.5kg), medium (MSW) (540.8±10.9 kg) and heavier (HSW) (605.8±28.3 kg). Animals in the HSW group resulted in higher carcass weight, LD area, crude protein content, pH24 value. On the other hand, L* and a* values color parameters and LD area per 100 kg carcass weight were significantly decreased with the increasing slaughter weight. The meat obtained from the LSW group were brighter and redder compared to other two slaughter groups. Additionally, there was a decreasing trend in the proportion of the non-carcass components with increasing of the slaughter weight. However, increasing of the slaughter weights led to a significant increase in the carcass measurements such as thoracic depth, carcass length, length of the round as well as width of the round. Although the crude protein content was significantly affected by both slaughter weights and muscle types, only muscle types were also significant sources of variation in percentages of moisture and crude ash.

Grass-based finishing of early- and late-maturing breed bulls within suckler beef systems: Performance, profitability, greenhouse gas emissions and feed-food competition

Demand for beef is increasing but concerns about the environmental impact of ruminant-protein production and food security are also increasing. Animal performance, profitability, greenhouse gas (GHG) emissions and feed-food competition within spring-calving suckler grass-based systems in which the males, progeny of either early- (EM) or late-maturing (LM) breed sires, were finished from pasture-alone or pasture-plus-concentrate supplementation, at 19.5 months-of-age, were evaluated. Sixty yearling bulls, previously offered grass silage ad libitum and supplementary concentrates during a first winter ‘store’ period, were assigned within breed type (EM or LM) to a pasture-finishing strategy of grass only (G-G) or grass + 3.2 kg dry matter of a barley-based concentrate daily (G-GC). Bulls rotationally grazed Lolium perenne-based swards over a 192 day grazing season. Concentrates were offered to G-GC treatments for the final 95 days following which all animals were slaughtered. The experimental data produced were used to populate a whole-farm systems economic and environmental model to determine beef output, profit, GHG emissions and feed-food competition of spring-calving suckler calf-to-beef systems. There were no finishing strategy × breed type interactions. Supplementation increased slaughter weight (+37 kg), carcass weight (+27 kg), carcass fat score (+1.1 units, 15-point scale), and resulted in more yellow subcutaneous fat. The LM bulls were heavier at slaughter (+65 kg), had a heavier carcass (+45 kg), greater kill-out proportion (+14 g/kg), a greater lean meat proportion in the carcass (+35 g/kg), superior carcass conformation score (+1.4 units, 15-point scale), lower carcass fat score (-1.2 units), and more yellow subcutaneous fat than EM bulls. Compared to G-GC suckler calf-to-beef systems, G-G systems had lower beef output, were less profitable, had higher GHG emission intensities (kg CO2 eq) per kg live- (10.2 v. 10.1), carcass- (18.6 v. 18.1) and meat- weight (26.1 v. 25.5), but superior human-edible protein (HEP) and energy efficiencies. The LM-sired systems were more profitable, had lower GHG emission intensities, and superior HEP and energy efficiency than EM systems. The HEP efficiency ratios exceeded 1.0 (i.e. were net producers of protein) for the G-G treatments and ranged from 0.9 to 1.0 for the G-GC treatments, when offered the ‘control’ barley-soyabean meal based concentrate: alternatively, using by-product concentrate feedstuffs increased the HEP ratios to 3.9 or greater. In conclusion, the existence of synergies and trade-offs between sustainability metrics makes the selection of a beef production system that optimises all performance metrics difficult.

Feeding and killing indicators of pigs using the drug “Kronocid-L”

The effect of feeding the drug “Kronocid-L” with the content of chelated compounds of trace elements on the productivity and slaughter performance of fattening pigs was studied. The scientific and economic experiment was conducted on two analogous groups of 75-day-old fattening young pigs, 12 heads in each, obtained from crossing sows of the large white breed with boars of the landrace breed. The experiment lasted 105 days and consisted of two periods: an equalization period (15 days) and a main period (90 days). The control group of pigs consumed the basic diet during the equalization and baseline periods. The compound feed “Grower” included: corn – 25 %, wheat – 25 %, barley – 23 %, sunflower meal – 12 %, wheat bran – 7 %, soybean meal – 3 %, BMVD – 5 %. “Finisher” compound feed included: barley – 38 %, wheat – 24 %, wheat bran – 12 %, corn – 9 %, sunflower meal – 9 %, BMVD – 4 %. In addition to the main diet, the experimental group was fed the drug “Kronocid-L” with the content of chelated compounds of microelements at the rate of 1 liter per 1 ton of water. The drug “Kronrocid-L” is a transparent green-blue solution that contains chelate compounds of trace elements (iron, zinc, manganese and copper), formic, acetic, orthophosphoric, lactic, citric, succinic and benzoic acids in an amount of 19 % by weight in an aqueous solution. Experimental animals that received the drug “Kronocid-L” during the first stage of the main period (75–110 days) and the second stage of the main period (111–165 days) outweighed the pigs of the control group by live weight by 5.9 and 7.4, respectively %, with an average daily increase of 9.5 % (P < 0.05) for the entire period of fattening. The use of the drug “Kronocid-L” at the rate of 1 liter per 1 ton of water allows to reduce feed consumption by 6.2 %, which is 3.0 kg per 1 kg of growth. At the end of the scientific and economic experiment, a control slaughter of experimental pigs was carried out, 4 heads from each group. It was established that feeding pigs on fattening with the above-mentioned preparation contributes to an increase in slaughter weight and slaughter yield in the 2nd experimental group, respectively, by 12,8 kg or by 15 % (P < 0.05) and 5.6 % (P < 0.05) against benchmarks. At the same time, under the influence of the feed additive, the thickness of the lard above the 6–7 thoracic vertebra decreased by 3.2 mm or by 10 % (P < 0.05) and the area of the “muscle eye” increased by 2.8 cm2 or 6 % P < 0.01).

Effect of slaughter weight and feeding system on some meat Quality and palatability of hamdani lamb carcasses

This study was conducted on hamdani lambs to compare two systems of feeding , The first system was ad libitum feeding on concentrate ration and the second system was grazing on pasture with supplementation of concentrate ration as in the first system at 1.5 % of animal body weight in order to reach two slaughter weight 35kg and 45kg . The results of this study showed significant increase( p< 0.05 ) in muscular and bone tissue percentages as well as in moisture, protein and ash percentages in lamb carcasses with tail fat for the second system , while increasing slaughter weight from 35kg to 45kg caused significant decreas( p< 0.05 ) in muscular and bone tissue also moisture percentage and significant increase ( p< 0.05 ) in fat tissue percentage and fat percentage in lamb cacasses with tail fat . Study did not show any affectivness in palatability of meat by the factors above .So we sow some improvement in meat quality characters in the second feeding system and no benefit in meat quality by increasing slaughter weight for 45kg .

Dietary Valine/Isoleucine Ratio Impact Carcass Characteristics, Meat Edible Quality and Nutritional Values in Finishing Crossbred Duroc × Landrace × Yorkshire Pigs With Different Slaughter Weights.

The aim of this study was to investigate effects of dietary ratio of valine to isoleucine [R(V/I)] on carcass characteristics and meat quality of finishing pigs and whether slaughter weight influence the effect. We carried out a 2 × 3 factorial trial with two slaughter weight (105 vs. 130 kg) and three R(V/I) (0.58, 1.23, and 2.60 at 75–100 kg body weight, and 0.70, 1.24, and 2.39 at 100–135 kg body weight for L-, N- and H-R (V/I), respectively). Data show that increasing slaughter weight significantly increased meat color (a*45 min and b*45 min), drip loss and shear force (P < 0.05). Meanwhile, increasing slaughter weight reduced sarcomere length, the proportion of protein-bound water, and most kinds of muscular total amino acid contents except for tryptophan and arginine, while increased contents of muscular free lysine, tryptophan, leucine, isoleucine, valine, alanine, and arginine in the M. longissimus thoracis (P < 0.05). Health lipid indices based on fatty acid composition of intramuscular lipid were improved as the slaughter weight increased (P < 0.05). Notably, pigs received N-R (V/I) diet improved carcass traits in terms of thinner backfat thickness and higher fat-free lean index, as well as increased meat flavor-contributing amino acids at the cost of reduced intramuscular fat content and increased shear force of cooked meat compared with the pigs fed L-R (V/I) and H-R(V/I) diets (P < 0.05). H-R (V/I) diet decreased ultimate pH value and sarcomere length of the skeletal muscle but increased the proportion of free water (T23), consequently, increased drip loss and cooking loss of fresh meat in pigs (P < 0.05). In conclusion, both slaughter weight and dietary ratio of valine to isoleucine exerted significant impacts on carcass characteristics, meat quality and nutrition values. In particular, carcass traits and meat color of lighter pigs were more susceptible to the influence of dietary R (V/I) relative to heavier pigs.

Dietary Cinnamon Bark Affects Growth Performance, Carcass Characteristics, and Breast Meat Quality in Broiler Infected with Eimeria tenella Oocysts.

Simple SummaryAntimicrobial tolerance problems have culminated in an increased focus on raising broiler chickens without using any antibiotics, and an increasing interest has developed in non-antibiotic feed supplements with potential productivity and health benefits. Previous studies have shown beneficial results linked to the addition of cinnamon to broiler diets under health conditions without induced coccidiosis. In this study, different amounts of dietary cinnamon, a phytogenic of the Lauraceae family, were evaluated for their effects on carcass characteristics and meat quality in broilers infected with oocysts of Eimeria tenella. Overall, emeriosis negatively affects bird slaughter weight, carcass yield, and most carcass traits. Compared with the positive control, cinnamon increased slaughter weight, carcass yield, and the percentage weights of heart, proventriculus, gizzard, breast, and pancreas. In addition, cinnamon at 2 g/kg diet improved performance, cocking loss, and meat tenderness among cinnamon groups. The ionophore salinomycin (Sacox®) group had the highest slaughter yield, myofibril fragmentation index (MFI), and texture profile analysis (TPA) of meat. The current research offers equivalent and unbiased findings from a study of substitutes for commercial coccidiostats in a consistent experimental paradigm that applies well to commercial conditions.A total of 150 broiler chicks were used to determine the impact of dietary cinnamon bark powder (CBP; Cinnamomum verum) on breast meat quality, growth performance, and carcass characteristics of birds under coccidiosis, as one of the protozoan parasitic diseases. A total of 5 replicates of birds received 1 of the following 6 groups for 34 days: control groups (1 and 2) received a basal diet without the addition of CBP or salinomycin; group 3 received a basal diet with 0.066 g salinomycin; groups 4–6 were given a basal diet supplemented with 2, 4, and 6 g CBP/kg feed, respectively. On day 21, 4 × 104/100 µL of Eimeria tenella oocysts/bird were challenged, except for the negative control (NC). At the end of the experimental trial, five birds/group were sampled for carcass characteristics and breast attributes. Overall, emeriosis negatively affects slaughter body mass, carcass yield, and the majority of carcass characteristics in birds, and cinnamon can mitigate these effects. Cinnamon groups, particularly at the 2 g level, alleviated the negative effect on performance caused by coccidia infestation to the same or greater extent as the negative control and salinomycin treatment groups. Furthermore, when compared with the other experimental groups, the addition of cinnamon improved some physicochemical properties with some affecting meat quality, such as decreasing MFI and increasing toughness in cinnamon-treated groups. In summary, it can be concluded that CBP can enhance the shelf life, carcass, and quality of birds’ meat by maximizing the productive performance efficiency and breast meat productivity of birds under coccidiosis infestation. Further research is required to investigate the use of cinnamon to optimize the quality of meat and the productivity of both healthy and diseased broilers.

Meat production traits of Angora goats. 2. Meat quality characteristics and fatty acid composition of meat from intact and castrated kids

Context In Turkey, meat production contributes much more income than mohair production in Angora goat farming. Castration is expected to alter the meat quality depending on the slaughter weight. Aims This study was designed to determine the quality characteristics and fatty acid composition of meat from intact and castrated male Angora goat kids slaughtered at different liveweights. Methods Forty-eight single male Angora goat kids (24 intact, 24 castrated) were slaughtered at three slaughter weights (20, 25 and 30 kg) after being fattened intensively. Response variables were meat physical quality characteristics, chemical composition, total cholesterol and fatty acid profile. Data were subjected to analysis of variance using the general linear model procedure. Key results Colour parameters (L*, a*, b*, C* and H*), pH, water-holding capacity and cooking loss were significantly (P &lt; 0.001) influenced by time post-slaughter. Castration did not affect (P &gt; 0.05) these properties. L* values decreased (P &lt; 0.001) as slaughter weight increased. With increasing slaughter weight, meat expressed less water and cooking losses were higher (P &lt; 0.001). Warner–Bratzler shear force increased (P &lt; 0.05) with slaughter weight. Castration affected meat chemical composition: moisture percentage decreased (P &lt; 0.001), and protein and fat increased (P &lt; 0.01). Similarly, protein and fat contents of the meat increased and moisture decreased with increasing slaughter weight (P &lt; 0.001). With increasing slaughter weight, intramuscular fat of the longissimus thoracis muscle showed increased polyunsaturated fatty acids (P &lt; 0.01) and ratios of polyunsaturated/saturated fatty acids (P &lt; 0.001) and n-6/n-3 (P &lt; 0.05), and decreased thrombogenic and atherogenic indexes (P &lt; 0.001). Total unsaturated/saturated fatty acid ratio was higher and atherogenic index lower following castration (P &lt; 0.05). Conclusions Castration of Angora male kids did not affect meat quality, but increased protein and intramuscular fat content of the longissimus thoracis muscle. Increasing slaughter weight positively influenced fatty acid composition pertinent to human health, but some measures indicated poorer meat quality. Implications Castration and slaughter weight did not greatly affect meat quality except for improvements in fatty acid percentages.

Індекс біологічної цінності м’яса курчат-бройлерів за експериментального випоювання антибіотику Даноксан-50

Індекс біологічної цінності м’яса курчат-бройлерів за експериментального випоювання антибіотику Даноксан-50

Fatty acid profilies and some meat quality traits at different slaughter weights of Brown Swiss bulls

This research was done to detect some meat quality traits and tissue fatty acid combination of the longissimus dorsi thoracis (LT) muscle of Brown Swiss bulls at the different slaughter weights (SW). The animal material of the study comprised 20 Brown Swiss bulls. In the study, Brown Swiss bulls were divided into two groups according to their SW as low (LSW (n = 10); 431-503kg) and high (HSW (n = 10); 504-583kg). In the study, the LSW group showed the lowest final pH value (pHF) (5.44) (P < 0.05). As the SW increase, the L* (lightness) value decreased in the LT muscle of Brown Swiss bulls (P > 0.05). In the research, the differences observed between the SW groups considering a* (redness) and C (chroma) values were found significant (P < 0.05). LT muscle water holding capacity (PL) decreased (P < 0.01) with increasing slaughter weight. In the study, the differences observed between SW groups in terms of drip losses (DL) after 3-day (DRP3) and 7-day (DRP7) storages and cooking losses (CL) determined were found insignificant (P > 0.05). Freeze-thaw loss (FL) and ether extract (PEE) were found 4.35% and 1.01% higher, respectively, in the HSW group than the LSW group (P < 0.05). Cholesterol content was determined as 66.15 and 70.68mg 100g-1 meat in LSW and HSW groups, respectively. The ratios of n-6/n-3 (P < 0.05) and PUFA/SFA (P > 0.05) in the LT muscle decreased with the increase of SW. As a result, when LSW and HSW slaughter weight groups were evaluated considering the water losses causing financial losses in meat and fatty acids having beneficial effects on human health, it was seen that the LSW group came to the fore.

Meat production traits of Angora goat 1: fattening, slaughter, and carcass characteristics of intact and castrated kids.

Fattening performance, slaughter, and carcass traits of intact and castrated Angora goat kids slaughtered at different slaughter weights were examined. A total of 96 (48 intact, I-kids, and 48 castrated, C-kids) single Angora kids were fattened, and 48 of them (24 I-kids and 24 C-kids) were slaughtered at slaughter weights (SW) of 20, 25, and 30kg. Castration negatively affected fattening performance, and the kids showed rising daily weight gain with increasing SW. While dressing percentages were not affected by castration, it caused a tendency for a decrease in offal. However, with the increase in SW, dressing percentages increased, and offal decreased. Castration increased non-carcass fat percentages and back fat depth. The proportions of individual cuts did not generally vary because of castration but changed with SW; foreleg percentages decreased (P < 0.001) while neck percentages increased (P < 0.05). Carcass composition was affected by castration; the percentages of carcass lean (P < 0.001) and bone (P < 0.01) dropped, and total fat (P < 0.001) increased. SW had an impact on carcass composition; the percentages of carcass bone (P < 0.001) declined, and lean (P < 0.001) and total fat (P < 0.001) raised as SW increased. The lean/fat ratio was affected by castration (P < 0.001) and increasing SW (P < 0.05). Castration reduced the lean percentage in all cuts. The leg showed the highest lean percentage, whereas the greatest fat ratio was found in the breast+flank in all SW groups. Consequently, castration of Angora male kids negatively affected fattening performance and altered the carcass composition, while the increase in slaughter weight improved fattening performance and slaughter and carcass characteristics.

Association Among Some Carcass Traits In Three Weight Groups Of Pigs

A TOTAL of seven hundred and eight Large White x Landrace pigs were slaughtered at three weight groups, 34.0, 55.0 and 92.0kg to collect carcass data. Of these 228, made of 118 castrates and 110 gilts, were slaughtered at 34 kg; 240 pigs, made up of 125 castrates and 115 gilts were slaughtered at 55kg, while a total of 240 pigs made up of 120 gilts and 120 barrows were slaughtered at 92 kg. Simple correlations as well as regression equations describing relationship among traits were calculated. &#x0D; Percent of lean cuts and separable lean in carcass decreased while fat cuts and separable fat increased with increasing slaughter weight. Such linear measurements as backfat thickness, loin-eye muscle area and carcass length increased significantly with increasing slaughter weights. Significant differences were obtained for several carcass traits between castrates and gilts slaughtered at 92 kg.&#x0D; Among the carcass cuts, percentage four lean cuts and loin showed highly significant and positive correlations with separable lean, while the relationship for other cuts such as the ham and shoulder, though significant, were low. Such carcass fat predictors as percentages separable fat, fat cuts and trimmed fat as well as back at thickness were highly significantly negatively correlated with separable lean, the relationship being highest for percentage separable fat. Dressing percentage and carcass length were poorly correlated with fatness or leaness, while loin eye areas was highly significantly correlated with leaness. The predictive values of the different traits remained relatively the same at the different slaughter weights, although the relationships were better at the 55 kg slaughter weight than at lower weights. The results indicate that while direct chemical determinations or complete physical separation are considered the best measures of carcass quality, the magnitude of the correlation coefficients between separable lean or fat and the different cuts suggests that these could be used with some degree of precision in appraising carcasses.

Effect of slaughter weight on carcass characteristics, meat quality, and lipidomics profiling in longissimus thoracis of finishing pigs

Slaughter weight greatly affect carcass characteristics and meat quality. Lipids are considered to be critical contributors to meat quality and vary with different physiological conditions. In this study, we investigated the carcass characteristics, meat quality, and lipidomics profiling of longissimus thoracis from finishing pigs with different slaughter weights. Increasing slaughter weight increased average backfat thickness (p < 0.01) and intramuscular fat content (p < 0.05), and decreased shear force (p < 0.01) and cooking loss values (p < 0.01). A total of 592 lipids from 19 lipid classes identified with lipidomics were analyzed. Phosphatidylcholine and phosphatidylethanolamine levels decreased with the increase in slaughter weight (p < 0.01). There were 101 and 76 significantly different lipids (variable importance in projection > 1, p < 0.05) observed in positive and negative ion modes, respectively. Fatty acids in phosphatidylcholine, specifically oleic and linoleic acids, were significantly altered by slaughter weight (p < 0.05). Our findings provide new insights into the effect of slaughter weight on lipid profiles and highlight the comprehensive lipid profile of pork from heavier pigs.

Effect of strain, sex and slaughter weight on growth performance, carcass yield and quality of broiler meat

Abstract This study examined strain, sex and slaughter weight effect on performance, meat quality and yield of broiler chicken. One hundred and fifty-day-old chicks (broilers) were distributed randomly in a 3 × 2 × 4 factorial experiment, with 50 birds per strain (Ross, Aboaca and Anak) and 25 birds per sex. After trial, 32 birds per strain and 16 per sex were slaughtered at 4 different body weights (1,000, 1,500, 2,000, and 2,500 g) to determine carcass yield and meat quality. The results revealed significant strain and sex effect (P &lt; 0.05) on growth performance of the broiler chicken. Ross strain had the highest feed intake (4883.25 g) and final body weight (2440.25 g) compared to Aboaca and Anak strains. Female broiler having heavier body weight (2431.66 g) and feed intake (4864.83 g) than the males for all strains. Aboaca birds had the highest carcass yields for all slaughter weight than Anak and Ross. The slaughter weight, irrespective sex and strains significantly influenced the carcass yield (P &lt; 0.001) with birds slaughtered at 2,500 g having (P &lt; 0.001) highest values compared to other slaughtered weights. As slaughter weight increases, cooking loss and thermal shortening decreases while water holding capacity and shear force values increases. Overall, Aboaca strain was considered to have best performances for production.

Effect of breed on growth performance and carcass quality attributes of apparently healthy male weanling rabbits under a conventional housing system

The present work was devised with an objective to assess growth performance and carcass quality attributes of male weanling rabbits of 5 different rabbit breeds (Dutch, New Zealand white rabbit, American black, wild, and dwarf brown) under a conventional housing system. Male weanling rabbits (n = 50; 10 per breed), weaned at about 4 weeks of age were studied for growth performance and carcass quality attributes at the 19th week of experimentation. The initial and slaughter weights of the animals were significantly (P ≤ 0.05) different for all breeds, with the highest values noticed in wild rabbits (940.1 ± 48.2 and 1971.0 ± 632.0 g) followed by New Zealand white rabbits (792.1 ± 35.0 and 1594.0 ± 469.0 g) respectively. A similar trend was noticed inslaughter weight and daily weight gain per animal. Wild rabbits had significantly (P ≤ 0.05) higher values for live weight, chilled carcass weight, reference carcass weight, and dressing?out percentage (2500 ± 676.1 g, 2070 ± 445.0 g, 67 ± 3.2%, and 48 ±1.9% respectively) as compared to their counterpart breeds. The results for mean values ofweight percentages of tissue showed that only the hind limb percentage and bone percentage were found to be significantly (P ≤ 0.05) different among the 5 study breeds. It is concluded that breed is the main determinant of growth performance and carcass quality attributes in rabbits. In order to attain increased slaughter weight, heavier genotypes (wild and New Zealand white) are recommended.

Особенности накопления йода в мышцах кроликов на фоне использования антиоксидантов в липосомальной форме

Abstract. The problem of iodine saturation of livestock products for residents of most regions of our country requires a detailed study. One of the factors is the obtaining of livestock products enriched with organic iodine. The study of the degree of accumulation of iodine in the muscle tissue of rabbits at the background of the use of liposomal form of antioxidants enriched with organic iodine (LFA) was the main purpose of the research. Methods. An experiment on rabbits of the California breed were used. The first control group received the main diet (MD) in the form of a granular mixture. The experimental second group was given LFA based on White sea laminarias at the rate of 250 g per ton of feed mixture of MD. The third experimental group was injected with MD the LFA with Black sea Cystoseira. The formation of meat indicators, chemical analysis of muscle tissue, the level of accumulation of trace elements, including iodine in muscle tissue was studied indicators. Results. Based on the somatometric method of evaluating rabbits, it was found that the young animals of the experimental groups form a more eirisomus-type body (from 60 to 70 % of the total population). All indicators of the interactions of somatic parameters in the young groups II and III positive and highly significant correlation, and the correlation index of the density of the body correlated positively with body length (r = +0,67, p ≤ 0.01), chest girth (r = +0,86, p ≤ 0.001), length of loin (r = +0,61, p ≤ 0,01), the length of the backside (r = +0.71, p ≤ 0.001) and head measurement (r = +0,57, p ≤ 0.05). An improvement of the indicators of slaughter of experimental groups of young animals was stated. The slaughter weight increases by 12.2 %, and the mass of internal organs responsible for digestion by 4.5–43.8 %. A percentage of increase in muscle tissue during boning by 10.0–15.9 % and a decrease in the proportion of low-value parts in the carcass-bone tissue by 8.6–9.9 % was stated. Iodine in the average sample of muscle tissue of the experimental groups increases by 91.8 mcg (p ≤ 0.05) in animals of the second group and by 113.3 mcg (p ≤ 0.05) of the third group.

The effect of sex and slaughter weight on performance, carcass quality and gross margin, assessed on three commercial pig farms

Economic margins on pig farms are small, and changing slaughter weights may increase farm profitability. However, one can question if the optimal slaughter weight is the same for each sex. On three farms, crossbred pigs (n = 1128) were used to determine the effect of sex and slaughter weight on performance, carcass quality and gross margin per pig place per year. On each farm, an equal number of entire males (EMs), barrows (BAs), immunocastrates (IC) and gilts (GIs) were housed separately in group pens. Pens were randomly divided into three categories of different slaughter weights: 105, 117 and 130 kg BW. In BA, the high average daily feed intake (ADFI) and the lower capacity to gain muscle led to a higher feed conversion ratio (FCR) and lower lean meat percentage in comparison to EM and IC. In all sexes, ADFI and FCR increased with an increasing slaughter weight but the effect of slaughter weight on carcass quality varied between sexes. In BA and GI, slaughter weight had no effect on carcass quality, but in EM and IC, carcass quality improved at higher slaughter weights. Gross margin per pig place per year was calculated as gross margin per pig × barn turnover per year, taking into account fixed costs per round, feed costs and output price per pig. The slaughter weight that gained the highest gross margin per year differed between sexes. Slaughtering BA and GI at 130 kg BW, compared to 105 or 117 kg BW, decreased the gross margin per pig place per year due to the lower margin per pig and barn turnover at higher weights. In IC and EM, no difference in gross margin per pig place per year could be demonstrated between slaughtering at 105, 117 or 130 kg BW. In IC, the increasing gross margin per pig with increasing slaughter weights counteracted with the lower barn turnover. In EM, gross margin per pig did not differ between slaughter weights, but the effect of barn turnover was too small to demonstrate significant differences between slaughter weights on gross margin per pig place per year. In conclusion, slaughter weight has an impact on profitability in BA and GI: they should not be slaughtered at 130 kg BW but at lower weights, but no effect could be demonstrated in EM and IC.

Performance, Carcass Traits and Quality of Longissimus lumborum muscle of Santa Inês lambs

The aim of this research was to evaluate carcass traits and meat quality of finishing lambs in pastures with different leaf area index with or without high protein-mineral supplementation. In this study, forty-eight young Santa Ines rams were used, with an average initial body weight of 13.5 kg and an average age of 4 months. For approximately 10 h a day, the animals had access to pastures comprised of Cynodon spp cultivar Tifton 85. In vivo measurements, including body length, anterior and posterior heights, chest perimeter, rump and thoracic widths, were evaluated. Based on the data in this study, providing supplements for sheep improved the carcass composition as increased hot carcass weight, cold carcass weight, empty body weight, carcass yield, external and internal carcass lengths and thoracic depth. Moreover, supplementation increased slaughter weight, which accounts for the largest portion of the producer’s profitability. Although the use of supplements increases production costs, it also improved quantitative and qualitative characteristics of the meat, which could satisfy the consumer market. The meat from supplemented animals had a lower atherogenicity index compared to the control suggesting the meat from supplemented lambs is healthier to be consumed.

Interactive effects of feed allowance and ractopamine supplementation on growth performance and carcass traits of physically and immunologically castrated heavy weight pigs

One experiment was conducted to investigate the impact of feed allowance and ractopamine supplementation on growth, carcass and meat quality traits in barrows and immunocastrated male pigs. Eighty finishing male pigs (95.79 ± 1.71 kg) were allocated in a 2 × 2 × 2 factorial treatment design with two castration methods (CM) (physically (BA) x immunologically (IM) castrated pigs), two ractopamine supplementation programs (RAC) (0 vs 10 ppm in the feed) and two feeding allowance schemes (FA) (restricted (RT) vs ad libitum (AL)) from 131 to 160 days of age. RAC-fed pigs were heavier (P < 0.01) and RT pigs were lighter (P < 0.001) at the end of the evaluation period. Average daily weight gain was higher in IM (P < 0.05) and pigs fed diets without RAC and RT showed lower daily weight gain (P < 0.05). RAC improved feed efficiency regardless of CM and FA (P < 0.001). BA were fatter at 131 days of age (P < 0.001). RAC deaccelerated backfat deposition (P < 0.001) and improved lean muscle deposition (P < 0.01) after the 29-day duration of the trial. RAC increased slaughter weight (P < 0.01), hot carcass weight (P < 0.05) and lean muscle weight (P < 0.05). RT pigs showed decreased slaughter weight (P < 0.001) and backfat thickness was increased in BA fed diets without RAC (P < 0.01). BA pigs fed diets with 0 ppm RAC showed the highest backfat thickness and IM pigs fed diets with 0 ppm showed the lowest backfat depth (P < 0.01). IM AL pigs fed diets with 0 ppm showed the highest percentage of muscle and BA RT and BA AL pigs fed diets with 0 ppm showed the lowest lean muscle percentages (P < 0.01). Loin muscle area was reduced in RT pigs (P < 0.001) and increased by RAC (P < 0.05). Feeding RAC increased meat shear force (P < 0.01). In conclusion, our results confirm that rearing immunologically castrated males is a profitable alternative for pork producers and that feed restriction after the second vaccination negatively influences growth and carcass parameters, which can be partially compensated by ractopamine supplementation.