scholarly journals The potentials of using selection index in the assessment of breeding values of Holstein breeds in Serbia

2015 ◽  
Vol 31 (4) ◽  
pp. 523-532 ◽  
Author(s):  
D. Stanojevic ◽  
R. Djedovic ◽  
V. Bogdanovic ◽  
M. Popovac ◽  
P. Perisic ◽  
...  

The conducted research was aimed at constructing equations of selection index that would be used in the selection of the Holstein-Friesian breed animals in Serbia. The construction of the selection index includes the most important milk traits observed in standard lactation: milk yield (MY305), milk fat content (% MF305) and protein content (% MP305). The variance and covariance necessary for the construction of selection index are calculated using the mixed model by the method of least squares. The economic value of traits is expressed as a ratio of relative changes in costs per unit of traits included in the selection index. Livestock included in the research produced, in the first standard lactation, an average of 7681 kg of milk with 3.58% milk fat and 3.28% protein. The equation of the selection index presented in the paper is selected from the group of equations of selection index, as an equation with the highest correlation between the equation and the aggregate genotype, which amounted to 0.2156.

2010 ◽  
Vol 26 (5-6) ◽  
pp. 287-295 ◽  
Author(s):  
V. Pantelic ◽  
S. Aleksic ◽  
P. Stojic ◽  
R. Djurdjevic ◽  
Lj. Samolovac ◽  
...  

Cows which represent top of the genetic value of the population in regard to their traits are chosen for bull dams. Selection is based on origin, production performance (quantity of milk, milk fat and protein content), milking/dairy traits, reproductive indicators, exterior and linear type scores. This study included 292 cows of Simmental breed selected for bull dams on the territory of Republic of Serbia during one year. Selection of cows for herd of bull dams was done after finalized first and subsequent lactation. In this study, the effect of region and year of calving on milk traits is presented. Applying the method of least squares average value of milk production was obtained - 5.754,49 kg, milk fat content - 3,98% and quantity of milk fat - 230,24 kg. Regions had statistically highly significant effect (P<0,01) on all investigated milk traits. Year of calving showed no statistically significant effect on milk yield, yield of milk fat and content of milk fat (P>0,05).


Genetika ◽  
2018 ◽  
Vol 50 (1) ◽  
pp. 243-251
Author(s):  
Marina Lazarevic ◽  
Dragan Stanojevic ◽  
Vladan Bogdanovic ◽  
Vlada Pantelic ◽  
Nevena Maksimovic ◽  
...  

The research was performed on Holstein-Friesian and Black and White bull dams reared on five farms of Agricultural Corporation of Belgrade - PKB. The study included 575 lactations of cows selected as bull dams and their progeny calved in the period from 2007 - 2014 and represent progeny of 24 bulls. The following dairy traits were analysed in a standard lactation (305 days): milk yield (kg) - MY, milk fat content (%) - % MF, milk fat yield (kg) - MFY, protein content (%) - % PC and protein yield (kg) - PY. Holstein-Friesian bull dams and their progeny, in standard lactation, produced on average 9239.84 ? 1607.64 kg of milk, with a milk fat content of 3.44 ? 0.20 and protein content of 3.21 ? 0.12. The impact of bull - sire, year of birth, lactation order, farm, year and calving season was present at different levels of statistical significance on yield traits, while the genetic group had no influence on any of the milk traits. Bull - sire, year of birth, lactation order and calving season did not influence the variability of milk fat and protein content. Heritability of observed milk traits was medium to low. The content of milk fat and protein had the lowest values of heritability, 0.014, and 0.024, respectively. The heritability of milk yield, milk fat yield and protein yield was 0.293, 0.319 and 0.273, respectively.


2013 ◽  
Vol 56 (1) ◽  
pp. 536-546 ◽  
Author(s):  
W. Kruszyński ◽  
E. Pawlina ◽  
M. Szewczuk

Abstract. In the work presented an analysis was performed of the genetic values of conformation traits in cows and their relations with the genetic value of dairy traits, basing on dairy performance (milk, fat and protein yield) and conformation data, obtained for Polish Holstein-Friesian cows of the Black-and-White variety, born between year 2001 and 2004, and maintained in 21 herds in the region of Wielkopolska (central Poland). The genetic values for the data analysed were estimated using the BLUP method and a mixed model. For the traits analysed a genetic trend was estimated as well as genetic correlations between the dairy and conformation traits. The population analysed was divided depending on year of birth and production level. The results obtained show a systematic increase in the traits analysed (positive genetic trends), both for the dairy and for conformation traits (with the exception of temperament). The highest genetic correlations between dairy and conformation traits were obtained for the udder, temperament and dairy type, while the lowest for height at sacrum and calibre. The analysis of the genetic value of conformation traits in cows of different dairy production genetic values indicated that the highest results were obtained for the group of animals with the highest genetic dairy production value. In turn, the analysis of the genetic value of traits of cows born in different years did not show statistically significant differences, with the exception of height in the youngest group.


2011 ◽  
Vol 27 (3) ◽  
pp. 951-958 ◽  
Author(s):  
D. Kucevic ◽  
S. Trivunovic ◽  
M. Radinovic ◽  
M. Plavsic ◽  
Z. Skalicki ◽  
...  

Objective of this study was to analyze the effect of the dairy farm on milk traits of cows in Vojvodina. The research was carried out on small farms with 10 to 20 cows, medium farms with 20 to 50 cows, and large farms with over 50 dairy cows. The study included registered animals of Simmental (SM) and Holstein-Friesian breed (HF; including Red Holstein) in the first lactation for traits of milk yield and yield and content of milk fat. Total of 1323 first lactations were analyzed. The average milk yield (both breeds) in the first lactation of 305 days was 6295 kg of milk with 234,3 kg of milk fat and average milk fat content of 3,74%. Milk performance of cows varied significantly (CV=22,9% and SD=1447,8), as well as milk fat yield (CV=21,6% and SD=50,8). Large farms produced in average 6534 kg of milk, medium farms 6347kg and small farms 4717kg. Size of the farm exhibited significantly high effect on all observed traits, and the tendency was that farms with higher number of animals realize also higher average of production. Farm management and various breeding-zootechnical conditions present on farms had significant effect on milk performance of cows.


Author(s):  
Ewa Czerniawska-Piątkowska ◽  
Maciej Szewczuk ◽  
H. Kamieniecki ◽  
M. Adamski ◽  
A. Bruś ◽  
...  

The general aim of the present work was to compare dairy performance and some reproductive parameters of Holstein-Friesian (HF) cows imported from Sweden as an in-calf heifers, and their age mates in Poland. The animals were kept freely on the deep litter on the farm owned by Agro-company “Witkowo” and feeding was based on TMR (total mixed ration) system during whole year. All ration’s ingredients (bulky feed, concentrate, miscellaneous additives) were mixed and fed as all-mash. The feed ration depended from the physiological condition of a cow and it was composed of corn and grass ensilage, mash concentrate, crushed corn meal, brewer’s grains and beet pulp.Cows imported from Sweden as in-calf heifers obtained higher milk, fat and protein yield in both lactations comparing to home cows. Significant statistical differences were observed for kg of milk, kg of protein, for FCM (P<0.01) and for kg of fat (P<0.05) in 2nd lactation. Fat and protein content in milk was in average higher for home cows (P<0.01). Big differences (P<0.01) were observed in SBT (proportion of protein to fat content) and RTB (difference between concentration of fat and protein) at imported cows in 2nd lactation. As far as reproduction parameters (gestation interval, calving interval, insemination index) are concerned was cows from Sweden better too. Heifers from Sweden calved earlier. The usage of high genetic potential of imported cows is possible only with providing them optimum living conditions suitable to their needs.


Animals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 327 ◽  
Author(s):  
Angela Costa ◽  
Riccardo Negrini ◽  
Massimo De Marchi ◽  
Giuseppe Campanile ◽  
Gianluca Neglia

The buffalo milk industry has economic and social relevance in Italy, as linked to the manufacture of traditional dairy products. To provide an overview of the current status of buffaloes’ performances on a large scale, almost 1 million milk test-day records from 72,294 buffaloes were available to investigate milk yield, energy corrected milk, fat, protein, and lactose content, and somatic cell score (SCS). Phenotypic correlations between milk traits were calculated and analysis of variance was carried out through a mixed model approach including fixed effect of parity, stage of lactation, sampling time, month of calving, and all their interactions and random effects of buffalo, herd-test-date, and residual. Third-parity buffaloes were the most productive in terms of milk yield, while the lowest solid content was detected in sixth parity buffaloes. A considerable gap between primiparous and multiparous buffaloes was observed for milk yield, especially in early- and mid-lactation. Overall, SCS progressively increased with parity and showed a negative correlation with milk yield in both primiparous (−0.12) and multiparous (−0.14) buffaloes. Results suggested that, at the industrial level, milk of primiparous buffaloes may be preferred for transformation purposes, since it was characterized by greater solid content and lower SCS. Results of this study provide a picture of the Italian population of buffaloes under systematic performance records and might be beneficial to both dairy industry and breeding organizations.


Author(s):  
A Gavelis ◽  
V. Þilaitis ◽  
A Juozaitis ◽  
V. Juozaitienë ◽  
G. Urbonavièius ◽  
...  

The aim of this study was to evaluate relationship between milk progesterone concentration (P4) and milk traits at the start of estrus time and 12h after start of the estrus in dairy cows. The 96 milk samples of 48 Lithuanian dairy cows without reproduction disorders and 90–100 days after calving were evaluated. Cows were classified into two groups based on milk yield per day: less than 30 kg (n=20) and e”30 kg (n=28). Data were categorized by milk fat and protein content at the start estrus and 12h after start of estrus to evaluate relationship between P4 and milk traits examined. P4 at estrus time in dairy cows was significantly positively correlated with milk yield (P less than 0.001), whereas it was negatively correlated with milk protein (P less than 0.05-P less than 0.01) and fat at 12h after start of estrus. Dairy cows with F/P from 1.0 to 1.5 had the lowest P4 in milk. Results of the pregnancy in dairy cows were related with lower P4 and milk yield level (P less than 0.001), higher milk fat (P less than 0.05) and milk protein content (P less than 0.001). These cows had 1.90 times lower prevalence of the signs of subclinical ketosis (P less than 0.05) at estrus time when compared with non-pregnant cows. As a result, it was clearly demonstrated that P4 in dairy cows can help to evaluate and improve the reproductive properties of cows.


1995 ◽  
Vol 61 (1) ◽  
pp. 9-18 ◽  
Author(s):  
P. M. Visscher ◽  
M. E. Goddard

AbstractDirect genetic evaluation of profit was investigated as an alternative to a selection index. PROFk was defined as (net income)/(food requirement) until the start of the kth lactation, for k = 2 to 6. Genetic parameters such as heritabilities and genetic correlations were estimated for profit traits for Australian Holstein-Friesian and jersey dairy cattle. Heritabilities for profit until the start of a given lactation were moderate, ranging from 0·12 (for profit until the start of the second lactation in Holsteins) to 0·31 (profit until the start of the third lactation in Jerseys). Genetic correlations between profit traits were very high, and approached unity for most pairs of traits, so that profit early and late in herd life were nearly the same trait. Genetic correlations between profit traits and stayabilities until a given lactation were high, ranging from 0·71 to 0·97. Genetic correlations between profit traits and first lactation milk yield traits were approximately 0·80 for Holsteins and 0·90 for Jerseys. A single analysis urns carried out for lifetime profit using all data, including cows that were still in the herd at the time of data collection. Heritabilities were 0·13 for Holsteins and 0·19 for Jerseys. Genetic correlations between lifetime profit and first lactation yields were high. For the selection of dairy bulls, a multivariate analysis on a milk yield trait (e.g. protein yield) and profit until the last known lactation of bulls' progeny was suggested.


1980 ◽  
Vol 31 (2) ◽  
pp. 171-176 ◽  
Author(s):  
A. P. Mavrogenis ◽  
A. Louca

ABSTRACTThe effects of different husbandry systems on production characters of 616 purebred and crossbred sheep are reported. The Cyprus Fat-tailed (L), Chios (C) and Awassi (A) breeds were evaluated under intensive, semi-intensive and extensive production systems. The performance of crossbred (C × L, A × L and A × C) Cyprus Fat-tailed and Awassi sheep was compared under extensive husbandry conditions. Ewes on the intensive systems produced more milk, fat and protein (P<0·01), but with somewhat lower fat and protein content than those on the extensive or semi-intensive systems. Chios and Awassi ewes were superior to Cyprus Fat-tailed ewes in nearly all traits (P<0·1), but inferior in terms of fat and protein content (P<0·1). Awassi × Chios crossbreds outyielded both purebred and crossbred sheep in terms of milk, fat and protein yield (P<0·1). Lactation number had a significant effect on milk traits. Maximum milk production was obtained at fourth lactation.


2000 ◽  
Vol 43 (2) ◽  
pp. 115-122
Author(s):  
H. Atil ◽  
A. S. Khattab

Abstract. A total of 1931 normal first lactation records of Holstein Friesian cows kept at Dena Farm in Egypt during the period from 1987 to 1994 were used to estimate phenotypic and genetic parameters for 90 day milk yield (90 dMY), 305 day milk yield (305 dMY) and lactation period (LP). In addition, 76 bulls with at least ten daughters were used to compare three methods of sire transmitting ability. A least Squares analysis of variance show significant effect of month and year of calving and age at first calving for different traits studied, except the effect of age at first calving on LP. Heritability estimates for 90 dMY, 305 dMY and LP were 0.39 ± 0.08, 0.27 ± 0.07 and 0.14 ± 0.05, respectively. Genetic and phenotypic correlations between different traits were positive and significant. Sires with at least ten daughters were evaluated by best linear unbiased prediction (BLUP), least Squares means (LSM) and regression of the future daughters mean on the present daughters mean. The product moment correlations between different traits studied were positive and high (= 0.96).


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