Silvester Žgur

Fatty acid composition of lamb meat from the autochthonous Jezersko-Solčava breed reared in different production systems.

Thirty two autochthonous Jezersko-Solčava lambs were used to investigate the effect of production (pasture vs. stable) and weaning system (suckling vs. weaned) on fatty acid composition of Longissimus dorsi intramuscular fat in a 2 × 2 factorial design. Pasture lambs had lower intramuscular fat concentration (P<0.0001) more PUFA and trans C18:1, more ALA (P=0.0322), ARA (<0.0001) and EPA (0.0149) but less SFA (P<0.0001) than stable lambs. Weaning system affected PUFA (P=0.0040) and MUFA (P=0.0070) but not SFA and trans C18:1 fatty acids. The interaction of production system and weaning system was significant mainly for trans C18:1 and trans C18:2 fatty acids. Finally, lamb meat from all four treatments which are traditionally used in rearing of Jezersko-Solčava lambs are favourable from the nutritive point of view, due to their low n-6/n-3 ratio.

The effect of α-tocopherol, sweet chestnut wood extract and their combination on oxidative stress in vivo and the oxidative stability of meat in broilers

1. This study examined the effect of α-tocopherol (α-T), sweet chestnut wood extract (SCW) and their combination on oxidative stress in vivo and oxidative stability of meat in broilers given diets rich in PUFA. 2. A total of 60 male broilers were individually caged and divided into 6 groups of 10. The C-PALM group received a diet with 7·5% palm fat and the other 5 groups with 7·5% linseed oil. The linseed oil groups were either un-supplemented (C-LIN) or supplemented with α-T or/and SCW as follows: αT-85 (C-LIN diet + 68 IU vit E as all-rac-α-T/kg), αT-200 (C-LIN diet + 183 IU vit E as all-rac-α-T/kg), SCW (C-LIN diet + 3 g SCW/kg) and αT-SCW (C-LIN diet + 68 IU vit E as all-rac-α-T/kg + 3 g SCW/kg). Different parameters of oxidative stress were measured. 3. Linseed oil induced DNA fragmentation and malondialdehyde (MDA) formation, while α-T reduced both parameters, and SCW reduced the DNA damage. A combination (αT-SCW) also reduced plasma MDA. Larger antioxidant capacity of lipid soluble compounds were recorded in groups αT-85, αT-200 and αT-SCW than in the controls but there were no differences between these groups in antioxidant enzymes and total antioxidant status. A combination (αT-SCW) increased tocopherol concentrations in breast muscle and in comparison to the C-LIN group MDA concentrations were reduced in groups αT-85, αT-200 and αT-SCW. 4. It can be concluded that neither of the α-T concentrations were able to prevent all the negative effects of lipid oxidation in vivo and only high concentrations of α-T improved the stability of meat. With the exception of DNA damage, SCW had no impact on in vivo and in vitro measured markers of oxidative stress but may have a sparing or regenerating effect on α-T.

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.

Improvement of pork characteristics under commercial conditions with small amount of straw or hay

ABSTRACT The objective of this study was to evaluate the effect of small amount of straw or hay (100 g/animal/day) and gender on pork characteristics, measured on slaughter line in longissimus dorsi et lumborum (LD) and semimembranosus (SM) muscles. We performed two replicates, each including 96 fattening pigs (half gilts and half barrows) reared under commercial conditions. Treatment had no effect on carcass characteristics and pH45 in both muscles. The straw and hay treatments lowered pH24 in LD muscle (straw: 5.71, hay: 5.74, control: 5.85), while hay treatment increased Fibre Optic Probe value (FOP24) in SM muscle compared to straw treatment (hay: 33.15, straw: 29.26). Gender had no effect on meat characteristics, but the interaction between treatment and gender revealed differences in FOP24 in SM muscle in gilts but not in barrows. Based on pH24 in LD muscle, straw treatment lowered percentage of pigs with DFD meat (straw: 6.2%, control: 28.6%), whereas based on FOP24 in SM muscle, hay treatment lowered percentage of pigs with DFD meat (hay: 9.4%, straw: 32.8%; control: 27.0%). We conclude that a small amount of straw or hay has a beneficial effect on meat quality as it lowered the incidence of DFD meat.

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.

Effects of Olive Leaf and Marigold Extracts on the Utilization of Nutrients and on Bone Mineralization using Two Different Oil Sources in Broilers

The aim of this study was to investigate the effects of olive leaf and marigold extracts on the apparent total tract digestibility (ATTD) of the principal nutrients and energy, as well as on mineral utilization (Ca, P, Mg, Mn, Fe, Cu and Zn) in relation to bone characteristics in broilers fed walnut- or linseed oil-supplemented diets. Thirty-six 12-day-old commercial broilers Ross 308 were reared in metabolic cages, assigned to one of the six dietary treatments (3 × 2 factorial design): three supplements (not supplemented, olive leaf extract, or marigold extract), and two oils (walnut or linseed oil). The results showed that the marigold extract reduced Zn and P balances and tended to lower the balance of ash and Mg, and the ATTD of Zn and Mg. Diets with linseed oil increased the ATTD of acid detergent fiber and reduced the ATTD of the organic residue and Cu. No differences in the bone characteristics of tibia were observed between treatments. These results indicated that the inclusion of marigold extract had a negative effect on the Zn and P balance, and that neither extract had any major effect on the digestion and utilization of energy and other investigated nutrients, or on bone mineralization, irrespective of the oil source included in the diet.

The effect of structural and biochemical changes of muscles during post-mortem process on meat tenderness

The aim of this paper was to describe the main structural and biochemical changes of muscles during post-mortem process implicated with meat tenderness. Taking into account complexity of biochemical and structural changes in muscles, meat tenderness is associated with the amount and quality of connective tissue, intramuscular lipid content (marbling), sarcomere length, and myofibrillar protein degradation. In short, more tender meat is associated with lower connective tissue content, higher collagen solubility, greater intramuscular lipid content, longer sarcomeres and greater myofibrillar protein degradation. However, it must be considered that the interactions among the listed factors are complex and dependent on numerous processes during post-mortem such as chilling regime, electrical stimulation, carcass suspension, aging, mechanical tenderization, different marinades, and thermal processing conditions.

Physicochemical properties of horse meat as affected by breed, sex, age, muscle type and aging period

The effects of breed, sex, age, muscle type (longissimus thoracis; LT vs semitendinosus; ST) and post mortem aging period (14 vs 28 days) on the physicochemical properties of horse meat were investigated. A total of 53 horses (21 females and 32 males) categorised into three groups (cold-blooded, CB; Posavje, P; crossbred, CS) were involved in this study. ST muscles showed a higher pH value, a greater intensity of lightness (L*) and yellowness, higher cooking losses and shear force values, and lower thawing losses than LT muscles. The breed affected only muscle redness, whereas sex had a minor effect on drip loss. An extended aging period was associated with higher thawing and cooking losses. An increase of age was followed by a decrease in pH value and L* value, and an increase in cooking loss and Warner–Bratzler shear force. An investigation of the interaction between muscle and aging showed that ST muscle with an aging period of 14 days had the lowest thawing losses. Among the numerous factors that can influence horse meat quality, the most important ones are age at slaughter and muscle type; these factors must be considered in the routine slaughtering practice and in further research.

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.