Marko Čepon

Effect of production system on fatty acid composition of meat from Simmental bulls

Abstract The objective of the study was to asses the effect of the production system on fatty acids (FA) composition of intra-muscular fat of three muscles (longissimus dorsi, semitendinosus, diaphragmae) from Simmental bulls. Bulls (n=8) were fattened either with maize silage and concentrates or on pasture. Grazing bulls showed a significant lower percentage of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA), but had higher percentage of polyunsaturated fatty acids (PUFA) and conjugated linoleic acid. The n-6/n-3 PUFA ratio was significantly lower (P<0.001) and the PUFA/SFA ratio was significantly higher (P<0.001) in muscles of grazing bulls. The lowest SFA percentage was found in semitendinosus (36.5±0.8) followed by longissimus dorsi (44.4±0.8) and diaphragmae (48.2±0.8) muscle. The percentage of PUFA and n-3 PUFA was the highest in semitendinosus muscle, while the n-6/n-3 PUFA ratio was similar in all three analysed muscles.

Effects of two finishing diets on growth performance, carcass characteristics and feeding behaviour of Slovenian Cika and Simmental young bulls

This study aimed at comparing the effects of a traditional finishing roughage-based diet and a higher energy diet, on growth, carcass characteristics, and feeding behaviour of Slovenian Cika and Simmental bulls (20 per breed). The experimental diets were: extensive (EXT) based on grass silage, and semi-intensive (S-INT) in which a part of the roughage was replaced with maize silage and sunflower meal. Each diet was fed ad libitum to 10 Cika (547 days old) and 10 Simmental (442 days old) bulls housed in group pens of five animals each. Growth performance was similar in both breeds, but Cika reached commercial finishing 1 month earlier than Simmental (139 vs 167 days; P = 0.016). Bulls fed S-INT had higher final weight (645.3 vs 590.1 kg; P = 0.05), average daily growth (1.05 vs 0.83 kg; P = 0.026), and feed intake (11.7 vs 10.6 kg dry matter (DM)/day; P < 0.001) than EXT bulls. Regardless of breed and diet, bulls ate 77–80% of the daily DM in the first 8 h after feed delivery. Bulls fed EXT showed longer standing (406.4 vs 355.8 min; P < 0.001) and eating (217.2 vs 155.3 min; P < 0.001) and shorter ruminating (77.5 vs 92.9 min; P < 0.001) times than S-INT bulls during the first 8 h of feed delivery. Cika bulls had lower full reticulo-rumen weights relative to slaughter weights (8.7 vs 10.7%; P = 0.002) than Simmental. The positive findings obtained with Cika cattle should encourage farmers to finish their young Cika male stocks for beef production, thus contributing to the maintenance of this animal genetic resource, and also to increase the energy density of the grass-based finishing diets by feeding supplements.

Growth and carcass traits of young bulls sired by Charolais and Limousin

Abstract A brown cattle is dual purpose cattle in Slovenia mainly used for milk production. This study included 90 crossbred young bulls of two genotypes, 70 Brown x Limousin (BRxLIM) and 20 Brown x Charolais (BRxCHA). The aim of this study was to determine some growth and carcass characteristics of crossbred young bulls. Data were analysed by GLM procedure considering sire breed and year nested within sire breed as fixed effects and slaughter age as linear regression. Sire breed statistically significantly affected slaughter weight, hot carcass weight, net daily gain, dressing percentage and index of conformation. All three included effects statistically significantly affected only slaughter weight, hot carcass weight and net daily gain.

Carcass and meat quality of young Cika and Simmental bulls finished under similar conditions

Twenty indigenous Cika and 20 young Simmental bulls (slaughtered at 560–718 days) were finished on two diets (extensive vs semi-intensive). When fed similar rations, Cika bulls at a ‘suitable’ finished level, had a significantly higher dressing percentage (+2.5%), more total fat (+13.7%), a lower percentage of tendons (–22.7%) and bones (–7.7%), a higher lean meat to bones ratio (+8.1%) and a greater percentage of intramuscular fat (+45.9%) than the Simmental bulls. Their meat also had a significantly lower pH (–4.0%), higher redness (+13.74%), yellowness (+15.0%) and drip loss (after 2 days, +28.3%) and a more intense flavour (+6.1%). Cika fat contained higher proportions of saturated fatty acids (+6.86%) and less polyunsaturated fatty acids (–30.8%) than Simmental fat. However, it appears that the main difference between these two breeds were the slower growth rate of the Cika and their lower weight but greater age when a finished state was reached relative to the Simmental.

Carcass and lamb meat quality from improved Jezersko-Solčava flocks in Slovenia

Forty lambs (progeny of two different genotype sires and Jezersko-Solcava ewes) were used to evaluate the effect of slaughter weight, genotype and sex on non-carcass components, carcass characteristics, carcass cuts and meat quality of Longissimus dorsi. Twenty-eight lambs were progeny by improved Jezersko-Solcava (JSR) sire (JSR lambs) and twelve were progeny by Texel (T) sire (JSRT lambs). After 10 days of age lambs were fed with commercial concentrate and hay ad libitum. Lambs remained indoors with their dams until weaning at 60 days of age. Lambs were divided into three groups according to genotype/sire and slaughter weight. JSR lambs were divided into JSR-light group (6 males and 6 females) and JSR-heavy group (6 males and 10 females). All Texel sired lambs representing the third group of JSRT lambs (6 males and 6 females). JSR-light group was slaughtered at the average 29.5 kg of live weight, JSR-heavy group and JSRT group were slaughtered at the adjusted 44 kg of live weight. Slaughter weight had effect on all non-carcass components presenting JSR-heavy the highest percentage. JSR-heavy carcasses had higher carcass fatness and were longer and wider in shoulder and hindleg. Slaughter weight affected carcass cuts, having the JSR-heavy lower percentage of shoulder and hindleg, but higher percentage of rib with flank. JSR-heavy carcasses had redder meat than JSR-light. When comparing JSRT and JSR-heavy lambs, JSRT had lower percentage of liver and lungs and higher percentage of head and pelt. JSRT carcasses had lower fatness, better conformation score and better dressing proportion than JSR- heavy. The composition of hindleg showed that JSRT carcasses had higher percentage of muscle and lower percentage of bone in hindleg than JSR-heavy carcasses. Meat quality differ only in b* value with more yellow meat in JSRT than JSR-heavy. Sex had effect on liver, heart and head with higher percentages in males. Males had lower dressing percentage, lower carcass fatness and higher percentages of neck, chuck and shoulder and had lighter meat. It was concluded that progeny by Texel sire had better carcass characteristics especially dressing percentage, carcass fatness and carcass conformation. Slaughtering JSR lambs at 44 kg of live weight have as a result longer and wider carcasses with slightly higher carcass fatness score, greater muscle and lower bone percentage in hindleg than JSR lambs slaughtered at 29.5 kg of live weight.

Carcass traits of Charolais, Limousin, Black and White and crossbreeds of Charolais, Limousin and Belgian Blue x Black and White young bulls in Slovenia

Abstract The effect of crossing of Black and White (BW) cows with Charolais (CHA), Limousin (LIM) and Belgian Blue (BB) sires on carcass traits of their crossbred male offspring was evaluated. The crossbred bulls were compared with pure breed BW, CHA and LIM bulls. Bulls younger than 24 months and slaughtered in Slovenian slaughterhouses from 2005 to 2008 were included in the comparison. All crossbred genotypes had heavier carcass weight and better net daily gain than pure breed BW bulls. Within crossbred groups the CHAxBW bulls had the heaviest carcasses and the greatest net daily gain. Among all genotypes the best carcass conformation had CHA and the worst BW bulls. In the comparison to pure breeds the BBxBW bulls had for 1.1 of the class better conformation than BW and for 0.5 worse than CHA bulls. Within crossbreeds the BBxBW bulls had for 0.12 and 0.30 of the class better conformation than CHAxBW and LIMxBW bulls. Carcass fatness varied from 2.3 to 2.6 among genotypes, where the BBxBW buls had the lowest fatness score.

Estimation of genetic parameters for body weight in Charolais calves in Slovenia

Abstract The aim of the present study was to estimate genetic parameters for growth traits of Charolais calves in Slovenia. Analysed traits included birth weight (BW), weight at the beginning (WB) and at the end of grazing season (WE), as well as yearling weight (WY). Data were collected on 340 Charolais calves. The total number of records, including pedigree data (parents and grandparents) was 401 animals. (Co)variance components were estimated by REML method for the animal model that included fixed effects of sex, parity and year of birth in the models for all traits. Age of calves at the beginning of grazing season was included as linear regression in models for all traits except for birth weight. The age of calves at the end of grazing season, and age at approximately one year were included as linear regression in the models for corresponding weights. Random effects included direct and maternal additive genetic effects. Direct heritabilities (ha2) were decreased from 0.74 at birth to 0.19 at yearling weight. Inversely, maternal heritabilities (hm2) were increased from 0.04 at birth to 0.12 at all other included weights. Direct-maternal genetic correlation (ram) was negative for all weights except for yearling weight (0.10).