M.M. Petrovic

Simmental cattle breed in different production systems

The paper gives the analysis on the state in population of Simmental cattle reared in Europe with a special review on the state in Simmental cattle in our country which makes about 80 % total cattle fund in Serbia, and is characterized by a negative trend in the number of cattle, as well as by a low average milk production per cow. The most important results obtained by both domestic and foreign authors by means of various methods of improving Simmental breed and its raising in different systems have been shown. The directions for improving Simmental cattle according to the productive directions have been analyzed. Possible methods of improving the Simmental cattle in our country have been pointed out, which should be in accordance with already existing genetic potential of each actual population, its purpose (registered breeding stock, production breeding stock), as well as with the market needs for cow milk, milk products and meat (primarily beef meat, for export). A special emphasis has been given to the importance of organizing the production of meat in the cow-calf system in which Simmental breed, following the model of many European countries, should have good performance also in our country, if the same production should be organized in deserted hilly and mountainous regions. In this way we could contribute to more significant increase in overall beef production, and to reactivate unused natural resources as well.

Heritability, phenotypic and genetic correlations of the growth intensity and meat yield of pigs.

The five year study included two genotypes of gilts of performance tested gilts, Swedish landrace and crosses F1 generation SLxLY. Of total number (n=3600), 1709 animals were genotype SL and 1891 animals were genotype SLxLY. Measuring of back fat thickness in the loin part (FT1), between 3rd and 4th lumbar vertebrae, 7cm laterally to the back line; back fat thickness (FT2) and depth of the musculus longissimus dorsi (MLD) between the 3rd and 4th rib from the rear, 7cm laterally to the back line. Assessment of meat yield was done using the ultrasonograph apparatus Piglog 105. In regard to meat yield indicators, medium heritability values were established for FT1 h 2 =0.461, and high values for FT2 h 2 =0.639, and for meat yield h 2 =0.633. Low heritability was established for depth of MLD (h 2 =0.105), life daily gain (h 2 =0.110) and age at the end of test (h 2 =0.103). Established phenotypic correlations between fat thickness FT1 and FT2 were strong (rp=0.638); between fat thickness and meat yield very strong (rp=-0.880 to -0.895), and between fat thickness and MLD very weak and negative (rg=-0.103 to -0.216). Genetic correlations were stronger than phenotypic, so between fat thickness FT1 and FT2 the correlation was complete/full (rg=0.930), also between fat thickness and meat yield (rg=-0.979 to -0.982), whereas the correlation between fat thickness and MLD was strong and negative (rg=-0.627 to -0.653). Heritability values for fat thickness and meat yield show that these traits have high level of heritability and are transfered to the progeny, whereas the level and strength of their dependance show that by decreasing the fat thickness positive influences is exhibited on meat yield, and that by increasing of depth of MLD also the meat yield is increased.

The effect of gender and breed on some properties of pig meat.

This study was conducted to investigate differences in characteristics of muscles from male and female fatteners from Mangalitsa and Swedish Landrace pig breed. The research was carried out on three muscles: m. longissimus thoracis et lumborum, m. gluteus medius and m. triceps brachii. Compared to the Swedish Landrace, it was found out that the meat of the Mangalitsa had considerably higher intramuscular fat content (p<0.05). The highest intramuscular fat content was determined in male fatteners of Mangalitsa in m. gluteus medius (6.81%) and the lowest in female fatteners of Landrace pig breed in the longissimus muscle (1.12%). As for technological quality of meat, after cooking, meat from Mangalitsa pig had greater cooking weight loss compared to Landrace and also lower shear force (SF) values for longissimus, but higher SF values for gluteus muscle. Gender had no statistically significant effect on technological meat quality. It can be concluded, on the base of the results, that the Mangalitsa pig, had favourable meat quality traits, which are very desired for production of traditional meat products of high quality.

POTENTIALS OF SERBIAN LIVESTOCK PRODUCTION - OUTLOOK AND FUTURE

The paper describes the state of the livestock production in the Republic of Serbia including preliminary results from the 2012 census: according to preliminary data, 908.990 heads of cattle, 3.403.288 pigs, 1.729.278 sheep and 235.576 goats are reared in Serbia. Structural and institutional measures, and measures of credit support should be the main instruments for achieving the goals of progress in animal husbandry. Activities in the breeding-selection work should be carried out in accordance with the recommendations of international organizations (ICAR, INTERBULL, EAAP). One of the most important outcome of these activities should result in a level of over 80% of the total population of cattle, pigs, sheep and other species of domestic farm animals in Serbia included in the control of production performance (presently between 25 and 30%). Genetic improvement of cattle, sheep and pigs (milk, meat) is very complex. More efficient use of reproductive technologies (AI - artificial insemination and embryo transfer ET, etc.), also of methods for evaluation of breeding value of farm animals through new methods of evaluation of breeding value of cows and breeding bulls will contribute to faster genetic improvement of production traits of these species of domestic animals. New knowledge in mapping and gene transfer, marker assisted selection, in vitro embryo development, embryo cloning, sexing, etc., are improving rapidly, with new technologies being developed permanently. Breeding/improvement of cattle, sheep and pigs in through breeding - selection work should facilitate further improvement of fertility traits, growth rate, feed efficiency, carcass quality (higher percentage of muscle tissue in the body), the quality of milk and meat, resistance to disease and stress, etc.. [Projekat Ministarstva nauke Republike Srbije, br. TR-31053]

THE EFFECT OF THE LEVEL OF MILK YIELD ON THE REPRODUCTION TRAITS IN BLACK AND WHITE COWS

In this study a relationship between the milk yield and following reproduction traits: number of inseminations per conception (AIS), service period (SP), age at calving (AC), calving interval (CI) and birth weight (BW) is studied. The research involved dairy cows of European type of Black and White cattle which are being intensively improved by the genes of Holstein - Friesian breed. Mean values of general average for number of inseminations per conception, service period, age at calving, calving interval and birth weight are: 2.00; 98.78; 1088.08; 376.70 and 36.40, respectively. In general, the estimated phenotypic correlations (rp) between the milk yield over standard lactations and fertility traits were positive and unfavorable, and ranged from 0.24 for the relationship between milk yield and birth weight to 0.70 for relationship between milk yield and age at calving.

THE EFFECT OF CROSSING OF DOMESTIC SIMMENTAL BREED AND FRENCH FATTENING BREEDS ON CONFORMATION AND FAT COVER OF BEEF CARCASSES

Evaluation of conformation and fat cover of beef carcasses has great importance in modern systems of carcass quality evaluation. In this way, adequate price is achieved for every classified carcass side according to market demand. In this paper, the effect of experimental crossing of Domestic Simmental breed with Charolais and Limousine breed (N=96) on conformation and fat cover was investigated. Evaluation was carried out on the whole carcass and partially for certain parts of carcass according to special evaluation pattern/form (1-5). In regard to evaluation of carcass conformation, statistically significant differences (p<0,01) were established between crosses and Domestic Simmental breed. Crosses with Charolais achieved the highest score for conformation (3,94), the highest score for round conformation (3,77) and shoulder (4,06). Considerably more fat tissue on outside of the carcass was determined in Domestic Simmental breed (3,44) compared to crosses with Charolais (3,27). Presence of fat in pelvic cavity was more expressed in Charolais (3,34) and Limousine crosses (3,28), with better score for covering of kidneys (3,50 and 3,53) compared to Domestic breed (3,17).

CATTLE PRODUCTION - CURRENT SITUATION AND FUTURE DIRECTIONS OF DEVELOPMENT IN REPUBLIC OF SERBIA**

Number of heads of cattle in the last 11 years is constantly decreasing. In this period, number of cattle is reduced by 18%. Number of cows and pregnant heifers reduced by 14%. Data indicate that at the end of 2006 1,096.000 heads of cattle were registered. It should be pointed out that number of cows and pregnant heifers of 710.000 heads at the end of 2006 which are included in reproduction represent the future of Serbian cattle production in future. Dominant breeds are Domestic Spotted and Simmental cattle, participating by about 70% in total number, then crossbreds of Domestic Spotted and Simmental and Busha cattle participating with about 25%, and about 5% goes to Black and Red-White cattle of European White-Black and Holstein races. Production of cows milk is in slight constant increase. This can be explained by increased production of milk per cow. Genetic progress in milk traits was achieved by utilization of progeny tested bulls on milk and increased scope of artificial insemination of cows and heifers. Production of meat is in constant decrease which is consequence of reduction of total number of cattle as well as insufficient number of slaughterhouses with EU certificate. Of total quantity of produced meat, in Central Serbia 69.000 t and in Vojvodina 21.000 t of meat is produced. Starting from the current situation in cattle production, and on basis of previous practice, domestic and international, and development of cattle breeding, fast and efficient transformation of cattle production is necessary, enlargement of agricultural farms and forming of specialized farmers for production of meat and milk. Systems of certification and registration which would increase the product value should be introduced on specialized farms. Milk produced in this way can have added value on the market through special dairy products (hard cheeses, semi hard cheeses, white-soft cheeses and milk beverages). Agricultural households/farms specializing in meat production have objective - production of beef for domestic needs and export. Future of export of Serbian meat is first of all in production of beef of high quality which complies with demands of specific markets (Italy, Greece, etc.).

Properties and composition of carcass of domestic spotted young cattle of two preslaughter weights.

Objective of this research was to determine the slaughter properties and carcass composition of carcass sides derived from young cattle of Domestic Spotted breed, of pre-slaughter weights of 500 (group A) and 600 kg (group B). Heavier cattle had higher share of kidney fat in carcass, whereas the share of offals showed no significant differences. Statistically significant difference was registered only in share of toungue (P<0.05), that was higher in cattle of group A. Share of extra/premium (tenderloin), I category (round) and II category (loin, back, shoulder) showed no significant differences between groups of cattle. Statistically significant difference (P<0.05) was established in the share of III category carcass parts. Share of forearm and chest was significantly higher in lighter cattle (3.55% and 7.95%) compared to heavier animals (2.89% and 6.33%), whereas the share of subshoulder was considerably lower in group A (6.89%) compared to cattle of group B (9.73%). Data obtained by dissection of main carcass side parts differed significantly in regard to the share of muscle tissue in round and belly, that was significantly higher in cattle of group A (P<0.05). Share of fat tissue (subcutaneous and intermuscular) was higher in cattle of group B in almost all carcass side parts, however, statistically significant difference between groups was determined only in round, back, neck and subshoulder. Also, share of bones in chest differed statistically significantly (P<0.05) and it was higher in group A (20.09%) compared to cattle of group B (15.52%).

Changes in chemical and physicochemical characteristics during the production of traditional Sremska sausage.

The aim of this trial was to investigate changes in chemical and physico-chemical parameters during the production of traditional Sremska sausage (dry fermented sausage) from pork of three pig breeds: Mangalitsa (MA), Moravka (MO) and Swedish Landrace (SL). Analyses of all variants of sausages were carried out after stuffing (day 0) and on production days 3, 7, 14 and 21. The reduction in moisture during production caused the increase in protein, fat and ash contents (p<0.001) in all three variants of sausages, were found to be within the range for this type of sausages. Higher fat content in MA and MO sausages compared to SL variant was most likely a result of the different chemical composition of the meat from pigs of autochthonous breeds. All three sausage variants had a similar final pH value, but the mildest drop of pH was determined in MA sausages. Pig breed significantly affected (p<0.05) all three indicators of oxidative changes (thiobarbituric acid value, peroxide value and free fatty acid content). It was found that they were higher in SL compared with MA and MO sausages and to significantly increase during the production process.

Regression analysis of milk production traits in Simmental cows.

The relationship between milk production traits over whole lactations was evaluated across three generations of Simmental cows, i.e. between daughters, dams and grand dams, by a phenotypic regression analysis with whole lactation traits in the daughter generation being used as the dependent variables (x1), and those in the dam and grand dam generations being used as the independent variables (x2 and x3). The results were obtained from a sample of 1170 daughters and as many dams and grand dams. The significance of the partial regression coefficients b2 and b3 was separately evaluated by a t-test. An analysis of variance was used to estimate the significance of the simultaneous effect of the production traits of dams and grand dams on the milk production achieved in the daughter generation. The calculated value of the partial regression coefficients for the whole lactation production traits across three generations (grand dams, dams and daughters) and their statistical significances determined by the t and F tests, as well as the regression equations used, suggested that the effect of the grand dam generation on the milk production traits in granddaughters was substantially lower than the effect of dams. The calculated partial regression coefficients (b2 and b3) were positive and statistically very significant (P<0.01), excepting the regression coefficients b3 for lactation length and b2 for milk fat content that were not statistically significant (P>0.05). A very significant change (P<0.01) was observed in all production traits in the daughter generation as simultaneously affected by the traits in the dam and grand dam generations.