This study was conducted in five dairy farms with different capacity (farms A with 47, B 12, C 10, D 14 and E 24 Simmental cows, aged between 4 and 5 years and body weight about 600 kg) in order to determine a relationship between rearing system, Animal Needs Index (ANI) and milk traits. Loose system of cow rearing was used in open stalls in farms A and C, while in other farms cows were tied in closed stalls. In two farms, there were outdoor pens, permanently available to cows on farm A, and during daytime on farm D. Rations for dairy cows were equal in all five farms and suitable for daily milk production about 20 kg with 4.0 % milk fat and 3.5 % milk protein. It was established that total ANI scores for farms were A 35.5, B 9.5, C 24.5, D 26.5 and E 10.5. The welfare levels in farms B and E were not sufficient, in farms C and D were very good, while in farm A it was excellent. A very significant influence of rearing system on cow welfare was found (p<0.001). A significant influence of rearing system (p<0.01) on average daily milk yield, milk yield in standard lactation, milk fat (kg), yield of 4 % fat corrected milk and yield of proteins (kg) were noticed. The influence of the rearing system on milk fat content (%), dry matter (%), protein (%) and lactose (%) was not statistically significant. Differences between ANI score, daily and standard lactation milk yield were very significant (p<0.001), as well as differences between ANI and the amount of milk fat (kg), protein (kg) and amount of 4 % fat corrected milk.

This research paper gives an analysis on the size of world?s domestic buffalo populations, their milk production and the size of buffalo population in Serbia. Population of domestic buffalo in the world is constantly increasing so that in 2013 there were 199 783 549 individuals, out of which in India in the same year they raised 57.77% of buffalo world population, in Pakistan 18.87%, and in China 11.64%. The share of total world production of buffalo milk in total world milk production in 2012 was 12.92 % or 97 417 135 t out of which 67.76% was produced in India. In Serbia buffalo is raised in the regions of Raska (about 1000 individuals) and Kosovo. Populations of buffalo in central Serbia show a tendency of decreasing in size what was the reason to start a programme of in situ conservation 10 years ago. On the sample of buffalo population encompassed by the programme of conservation the body measures were analysed indicating that the population of buffalo is quite unequalised and that average values obtained for exterior measures are similar to the results obtained by the authors of earlier period for the population of buffalo in the area of former Yugoslavia. [Projekat Ministarstva nauke Republike Srbije, br. III 46009 i br. TR31086]

The most significant welfare problems in dairy calves in intensive rearing conditions have been investigated in this paper. These problems mainly result from inadequate intake of colostrum (separation from the dam), inadequate ventilation (resulting in inappropriate airflow, low or high temperatures, high humidity and poor air quality), poor floor conditions (wet floor, without bedding), inadequate monitoring of health, exposure to pathogens causing respiratory and gastrointestinal disorders and occurrence of iron deficiency. In addition, on cattle farms in our country welfare problems in calves originate from continuous restocking (no "all in - all out") and mixing calves from different sources, as well as insufficiently balanced solid food, insufficient access to water and generally poor response of farmer to health problems, especially necessary dietary changes. A special welfare problem is insufficient floor space allowance which results in calf?s discomfort.

The aim of this research was to determine the influence of lactation number and parity on milk yield of Saanen goat’s breed. It has been concluded that milk yield was higher for goats that had given birth to twins and three kids than for goats that had given birth to a single kid (P<0.05). The longevity has a great positive impact on production, given that goats in the fifth lactation produced more milk than goats in first or second lactation (P<0.05), while goats in the sixth lactation still produced more milk than goats in first lactation (P<0.05). During the period from 2014- 2019, the research was conducted on a farm of multiparous Saanen goats in Vojvodina (northern part of Serbia). In the observed period, the farm had between 350 and 400 goats per milking, and the research included a total of 1,628 concluded lactations, within which the first lactations were the most 484, then the second 381. According to the number of lactations, goats were grouped into classes from one to seven and from one to three for parity. By comparing each individual lactation, it was determined that in first lactation goats produced significantly lower milk than goats in the rest lactations(P<0.05), except the seventh. Research has shown that lactation number has a significant influence on milk yield (P=0.00). Increasing the fertility of goats significantly affects the production capacity of dairy goats, since does with a larger number of kids in the litter had a significantly higher milk production (P<0.05). Due to the larger number of kids in the litter, milk production also increases. Likewise, it is assumed that the increase in milk yield of goats with two and three kids is a consequence of a larger placenta, i.e. stronger lactogenic activity during pregnancy.

The objective of this research paper was to estimate heritability coefficients (heritability) of growth traits in the lambs of indigenous Sjenicka Pramenka breed. The research was conducted on a sample which included 421 lambs the descendants of 15 sires and 187 sheep-dams, raised on 3 private farms in Kolubarski district, Serbia. The effect of fixed factors was studied while the values of heritability coefficients were estimated within the frame of SAS software package. A statistically highly significant (**=P<0.01) effect on studied traits had following parameters: sex, year of lambing, type of lambing, farm and method of applied reproductive technology. By means of REML method and using the sire model the values of heritability coefficients were determined for the following traits: average lamb birth weight (BW0), average lamb body weight at 30 days (BW30) and average lamb body weight at 90 days (BW90) being: 0.0355; 0.4642 and 0.3018, respectively. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31086]

nema

Abstract:In this paper, fertility parameters of sheep are discussed and principles analyzed in order to obtain the optimal methods for their evaluation. Mathematical procedures for evaluation of genetic and phenotypic parameters and anticipation of genetic values, today, are mainly based on different linear and non-linear concepts, therefore it is necessary to accept the reality that there is no absolute accuracy. Special emphasis is on the possibility of use of physiological quantitative fertility indicators in sheep selection, considering that there is correlation between them and fertility traits. In this regard, the degree of response to direct and indirect selection within population is analyzed in order to established the nature of parameters necessary for evaluation of data and determine the relative degree of such response.

Considering that total variability of milk traits in sheep within single population greatly depends on factors of genetic nature, objective of this paper was to investigate the trend of genetics parameters in populations raised in Pirot region, in order to create more efficient selection program in regard to milk production. Obtained and processed results of investigation have demonstrated that investigated traits occupy central heritability values. Degree of heritability for protein and fat had higher values in relation to other observed traits. Weak and negative genetic correlation is present between fat content and other traits whereas strong and positive correlation was determined for milk quantity and fat content and protein. Statistical analysis confirmed absence of significant differences between sheep of Pirot Pramenka breed and improved Pirot population. This research has also demonstrated that in selection of sheep in regard to milk traits and production special attention should be directed to importance of genetic parameters considering that with the increase of quantity of milk not only content of fat but also of protein are reduced, which can influence the economical efficiency on farm in system of payments for milk according to its quality.