Features and Possibilities for Optimizing Farm Milk Production in Serbia

Milk production in Serbia is organized on farms of different capacities that mutually vary in relation to agro-ecological, zootechnical and production conditions. The aim of this paper is to present a part of the most important results that have been obtained so far, in the implementation of the project “Optimization of technological procedures and zootehnical resources on farms with the goal to upgrade sustainability of milk production”. The results that are presented relate to the most important features of farm cow milk production in Serbia, as well as the possibility for optimization of the most important technological procedures and zootechnical resources on which milk production is based. The structure of dairy farms in Serbia, in terms of size and number of animals, is not satisfactory, because the predominated types are small and medium scale farms. However, there are numerous possibilities for optimization of farm and zootechnical conditions and resources in order to improve the sustainability of milk production. These possibilities can be divided into optimizing selection and breeding methods, optimizing nutrition manners and physical form of forage and complete meals in the nutrition of dairy cows, optimizing housing conditions, welfare and health care in order to improve the sustainability of milk production, as well as optimizing milking and handling the milk after milking

The Effect of the Use of Sexed Semen on Reproductive Traits and Sex Ratio of Black and White Calves

Sperm sexing is a relatively new biotechnological procedure which offers us the possibility to choose the offspring sex. This method is widely used today in the insemination of the dairy cattle breeds and it is based on the difference in total DNA quantity between X and Y chromosome spermatozoa. In this research paper we have analysed the fertility, sex ratio and characteristics of female Black and White breed calves inseminated by the sexed sperm produced by 6 bulls on 6 commercial farms of the PK Belgrade. Conception rate was 44% with average gestation length of 274.9 days. Average calf birth weight was 36.75 kg. The stillbirths and twinning rates were 7.16 and 1.13%, respectively. Artificial insemination by sexed sperm assessed by c2 test highly significantly (P0.05) gestation length. Regardless the low conception rate, the application of sexed sperm in dairy cattle breeding is very significant since it enables the breeders to use the best replacement female animals what may result in the improvement of genetic basis of breeding stock

The State and Development Prospects of Goat Production in the World

Goats are the most popular animals in the world and goat meat and milk consumption are most widely distributed in the world. Goats are popular with small holders because of their efficient conversion of feed into edible and high-quality meat, milk and hide. Goats are also used as holistic tools for land vegetation management and fire fuel load control. With proper grazing management, goats can eliminate noxious weeds, restore native grasses and prevent fires through fuel load reduction. In the world the number of goats is increasing. However, when it comes to growing goats, the conditions prevailing today are fairly complex. Problems and prospects vary by region, which consequently have different cultural and economic implications. Both global and regional approaches to livestock farming are important from the economic aspect of developed and developing nations. Rapidly increasing goat populations in developing countries point to the goat assisting in solving some of the needs created by the rising human population. Goat farming in Europe also has a more positive outlook after nearly a century of a negative reputation. Dairy-goat farming is significant to the economies of the Mediterranean countries. Dairy goats produce about 15.2 million metric tons (MT) of milk, accounting for about 2% of the world total amount of milk produced by livestock species. The developing countries produce approximately 83% of the total amount. In Europe, goat breeding is strongly oriented towards milk production, with only 3% of the world goat population producing about 15% of the world’s goat milk, which is mostly used for cheese production. Goat meat is widely consumed in the developing countries. According to FAOSTAT (2008), total meat inventory is about 280 million MT. Goat meat represents only 2% of this total. The total amount of goat meat produced in 2008 was 4.9 million MT. The developing countries produced approximately 97% of this amount, reflecting the great importance of goat meat to feed millions of people in these countries. The top ten countries producing goat meat are all from Asia and Africa. China is a world leader in producing goat meat, accounting for 38% of the world total goat meat produced. Goat meat production has been increasing from 2.65 million MT in 1990 to 4.93 million MT in 2008

Simmental Breed Production Characteristics and Breeding Goals

This paper presents the most important production results obtained for the population of Simmetal breed raised in majority of the European countries which with a total population of about 9 million animals rates as the second biggest important cattle breed in Europe. Breeding goals from previous period were analysed along with newly defined breeding goals in some Simmental breed populations. Current mean values for milk yield of Simmental cows in standard lactation in the European countries range from 5500 to 7500 kg. Depending on the Simmental breed population in most countries a breeding goal set for first lactation cows is milk yield of 5500 or 6000 kg with 4.0% milk fat and 3.5% protein, while in cows who finished their third lactation required milk production is more than 7000 kg for Simmental breed, over 8000 kg for Simmental breed with share of Red and White Holstein genes and over 8500 kg for Montbeliard breed. A special emphasis is given on the prolonging of the duration of life and production span. During life span the demand is to produce minimum 30 000 kg milk/cow. This demand can be realised if functional traits in breeding goal participate with over 40 % with proper implementation of improvement programme. As for the traits that are significant for meat production, depending on the population, defined breeding goal for daily liveweight gain are values above 1500 g/day (i.e. 1400 g /day) for Simmental male bullcalves

PHENOTYPIC VARIABILITY OF FERTILITY AND MILK TRAITS IN OFFSPRING OBTAINED BY INSEMINATION BY SEXED AND CONVENTIONAL SEMEN OF HOLSTEIN BREED BULLS

The objective of this paper was to compare heifers reproductive traits and characteristics of their calves after artificial insemination performed by conventional (non-sexed) and sexed sperm on 6 commercial farms in Serbia. Conception rate was 55% and 44% for conventional and sexed semen, an average gestation length being 274.6 and 274.9 days, respectively. Average body mass at birth was 37.47 and 36.75 kg for non-sexed and sexed semen, respectively. The rate of stillbirths and twinning was 6.19 and 3.78% for conventional and 7.54 and 1.13% for sexed semen, respectively. The use of conventional semen exerted no statistically significant (P>0.05) effect on female: male calves relationship (51.96 : 48.04) while artificial insemination by sexed semen highly significantly (P<0.01) changed calf sex-ratio (85.10 : 14.90). First-calf heifers originating from sires whose sperm was obtained in conventional way produced 7880 kg milk with 269 kg milk fat and 242 kg protein in standard lactation, while first-calf heifers originating from sires whose sperm was sex-sorted produced 8184 kg milk with 251 kg milk fat and 242.3 kg protein. Type of insemination (conventional and sexed semen) did not significantly affect the studied milk yield traits (P>0.05)

Correlation analysis of milk production traits across three generations of Simmental cows

The relationship between milk production traits over whole lactations was evaluated across three generations of Simmental cows (between daughters, dams and granddams) by a corelation analysis with whole lactation traits in the daughter generation being used as the dependent variables (x<sub>1</sub>), and those in the dam and granddam generations being used as the independent variables (x<sub>2</sub> and  x<sub>3</sub>). The results were obtained from a sample of 1170 daughters and as many dams and  granddams. The correlation of whole lactation milk production traits between daughters, dams and  granddams, as calculated by simple, partial and multiple correlation coefficients was very weak or  non-existent. All of the calculated simple and partial correlation coefficients were positive and mostly  statistically very significant (P<0.01). The calculated coefficients of multiple correlation (R1.23) between  lactation length, milk fat content, milk yield, milk fat yield and 4% FCM yield with the expression of the traits in the daughters being used as the dependent variable and that in the dams and granddams as the independent variable were statistically very significant (P<0.01), amounting to 0.091, 0.251, 0.180, 0.133 and 0.153, respectively.Key words: Simmental breed, production traits, generation, coefficient of partial correlation, coefficient of multiple correlation

Životna proizvodnja mleka i mlečne masti kod krava simentalske rase

This study was conducted to evaluate the phenotypic expression and variability of lifetime performance traits (lifetime yields of milk, fat and 4%FCM, milk fat content, milk yield per milking day, milk yield per day of productive life and milk yield per day of life) and the effect of systematic factors (breeding region, total lactation number, year of birth and season of birth) and age at first conception on the above traits in 2548 Simmental cows. The test Simmental cows achieved the following: lifetime yields of milk, fat and 4%FCM - 14604, 554.8 and 14157 kg, respectively, milk fat content of lifetime milk yield - 3.81%, milk yield per milking day - 12.79, milk yield per day of productive life - 9.31 and milk yield per day of life - 5.46 kg. The marked variability of the traits, along with a certain percent of high-producing cows, enables further success in their selection.Ispitivanje fenotipske ispoljenosti i varijabilnosti osobina životne proizvodnje (životna proizvodnja mleka, mlečne masti i 4%MKM, sadržaj mlečne masti kao i proizvodnja mleka po muznom produktivnom i životnom danu) izvršeno je na uzorku od 2548 krava simentalske rase. Na analiziranom uzorku simentalskih krava ostvarena životna proizvodnja mleka, mlečne masti i 4%MKM iznosila je 14604, 554.8 i 14157 kg, sadržaj mlečne masti životne proizvodnje mleka 3.81%, dok je proizvodnja mleka po muznom, produktivnom i životnom danu iznosila 12.79, 9.31 i 5.46 kg. Izražena varijabilnost ovih osobina, sa izvesnim procentom visoko proizvodnih grla, omogućava dalji uspešan rad u njihovoj selekciji

Uticaj fiksnih i kontinuelnih ambijentalnih faktora na proizvodnju 4% mast-korigovanog mleka u prve tri laktacije kod krava simentalske rase

The effect of paragenetic factors on 4% FCM yield in complete and standard lactations was studied in 241 Simmental cows. Farm, lactation number, birth season, calving season, their interactions and age at first conception were evaluated for their effect on the trait. The mathematical and statistical analysis of the data obtained, i.e. least square means, standard error, analysis of variance and coefficient determination, were calculated using the General Linear Model procedure. The effects of farm, lactation group and year of birth on the trait were very highly significant (P 0.05) on the production of 4% FCM, either in whole or in standard lactations. The interaction between birth season, calving season and year of birth was variable and ranged from insignificant to very significant. Age at first conception produced a significant (P0.05) effect on 4% FCM yield in complete and standard (bxy=0.693ns) lactations, respectively.Uticaj paragenetskih faktora na proizvodnju 4%MKM u celim i standardnim laktacijama ispitivan je na uzorku od 241 krave simentalske rase. Na ispoljenost ove osobine ispitivan je uticaj farme, broja laktacija, sezone rođenja i telenja, njihovih interakcija i uzrasta pri prvoj oplodnji. Matematičko-statistička analiza podataka, odnosno sve potrebne veličine, kao što su sredine najmanjih kvadrata, standardne greške, analiza varijanse i koeficijenti determinacije izračunate su u programskoj proceduri Opšti linearni model (GLM procedura). Uticaj farme, grupe laktacija i godine rođenja na ispoljenost ove osobine bio je vrlo visoko značajan (P0.05) na proizvodnju 4%MKM kako u celim tako i standardnim laktacijama. Uticaj interakcije između sezone rođenja,, sezone telenja i godine rođenja bio je varjabilan, i kretao se od nesignifikantnog do vrlo značajnog. Uzrast pri prvoj oplodnji statistički značajno (P0.05). Koeficijenta determinacije (R2) bio je vrlo visoko značajan (p<0.001) i kretao se od 0.623 kod proizvodnje 4%MKM u celim do 0.652 kod proizvodnje 4%MKM u standardnim laktacijama

IMPACT OF CLIMATE FACTORS, BREED, AND BOAR UTILIZATION FREQUENCY ON SEMEN QUALITY AND SPERM MORPHOLOGY

The primary objective of this research was to evaluate boar ejaculate variability and the occurrence of anomalies in spermatozoa, considering climatic factors during spermatogenesis breed, and utilization frequency. This study involved 17 boars (n=129 ejaculates) and fertility testing was conducted during the most critical period of the year, from August to October. The observed sperm characteristics included: ejaculate volume (VOL), sperm concentration (CON, spermatozoa/ml), total number and number of functional spermatozoa (NT, NF), percentage of sperm motility in the native ejaculate and after dilution (MOTN, MOTD), number of produced doses (NPD), percentage of dead and live spermatozoa (PM, PZ), and sperm anomalies. The assessment of the effect was performed using a General Linear Model procedure. The breed did not influence sperm variability, while the frequency of boar utilization impacted on the occurrence of secondary anomalies. The determined regression coefficient indicated that extending the interval by one day increased PPPK by 0.340-0.348%. The maximum daily temperature during semen collection (model 1) and the value of the TH index during semen collection (model 3) influenced ejaculate volume. An increase of one ℃ in temperature, or one unit in THI value, led to a (p<0.05) increase in VOL by 3.540 ml and 2.798 ml, respectively. Furthermore, the maximum daily temperature (model 2) and the TH index value (model 4) at the beginning of the epididymal phase of spermatogenesis had an impact on semen motility, as well as the percentage of live and dead spermatozoa