scholarly journals Effects of Correction for Heterogeneity of Variance on Bias and Accuracy of Breeding Value Estimation for Dutch Dairy Cattle

1994 ◽  
Vol 77 (10) ◽  
pp. 3174-3184 ◽  
Author(s):  
J.H.J. Van Der Werf ◽  
T.H.E. Meuwissen ◽  
G. De Jong
2013 ◽  
Vol 96 (4) ◽  
pp. 2627-2636 ◽  
Author(s):  
L. Rönnegård ◽  
M. Felleki ◽  
W.F. Fikse ◽  
H.A. Mulder ◽  
E. Strandberg

1989 ◽  
Vol 48 (2) ◽  
pp. 283-291 ◽  
Author(s):  
Susan Brotherstone ◽  
W. G. Hill ◽  
R. Thompson

ABSTRACTWith a view to incorporating identifiable environmental factors such as month of calving as random effects in models for dairy sire and cow breeding value estimation, an analysis was undertaken of environmental components of variance for fat yield in lactations 1 to 5 of pedigree British Friesian-Holstein cattle. Records of fat yield and of log fat yield on daughters of widely used sires were first corrected for age and month of calving and for sire in each lactation on a national basis. Variance components for herd-year, herd-year × lactation, herd-year × month of calving, herd-year × month of calving × lactation and error were then estimated for pairs of lactations.The results were most consistent for log fat yield, where heterogeneity of variance was less. Correlations were, approximately, 0·45 and 0·42 for records in the same herd-year and lactation for lactation 1 or a later lactation, respectively, and approximately 0·40 for records in the same herd-year and different lactations. Within herd-year and lactation, correlations of records in the same month were approximately 0·10 for lactation 1 and 0·08 for later lactations, and for different lactations the correlations were 0·06 if lactation 1 was included and 0·08 otherwise. Thus, the effects appear to be similar for later lactations, which can be pooled, but effects for month and month × lactation 1 v. later should be fitted.


Author(s):  
K.ZH. ZHUMANOV ◽  
◽  
T.N. KARYMSAKOV ◽  
M.A. KINEEV ◽  
M.V. TAMAROVSKIY ◽  
...  

According to the current “Instruction” used in dairy cattle selection and breeding in the Republic of Kazakhstan, bulls-producers of dairy breeds are assessed according to the their offspring quality based on the principle of “peer daughter”. This means that the phenotypic indicators of the daughters of the tested bulls are compared with the corresponding indicators of their peers. In European countries with developed dairy cattle breeding, as well as in Canada, the USA, etc., to ensure a reliable forecast of the genetic value of individuals (primarily, bulls-producers), use is made of the best linear unbiased forecast method (BLUP method). This method implies that the breeding value of producers is determined by the deviation values of the development of traits of the examined animal from its average values in the population. Especially urgent area is the research aimed at improving breeding programs, including assessing the breeding value of bulls-producers of dairy breeds using BLUP methods based on the productive qualities of the mass of dairy cattle in the Republic of Kazakhstan. The research material included the data on the phenotypic indicators of the milk productivity of first-calf cows (the amount of milk yield, the content of fat and protein in milk, the yield of milk fat and protein) of the Holstein black-motley dairy cattle breed, obtained from the information and analytical database of the Republic of Kazakhstan for 2016–2017. It was found that when evaluating according to the official “Instruction”, 16 sires out of 256 bulls (6.2%) got the stud category in 2016, 14 sires (9.2%) out of 152 bulls in 2017, and – 30 sires of 249 bulls (12.0%) over the cumulative period. The results of the conducted research prove that the use of the classic “Instructions” in dairy cattle breeding has lower efficiency (by 42.8–90.0%) as compared with the assessment of the breeding value of bulls based on the BLUP method.The selection of sire bulls into breeding groups based on the “peer daughter” methodology is not reliable enough and rather ineffective. Comparing the results of assessing the breeding qualities of sire bulls, obtianed using two methods in all compared periods (2016, 2017, 2016–2017), the authors established a clear superiority of the BLUP method over the current Instruction used in the Republic of Kazakhstan.


1994 ◽  
Vol 74 (3) ◽  
pp. 401-409 ◽  
Author(s):  
D. Perotto ◽  
R. I. Cue ◽  
A. J. Lee ◽  
A. J. McAllister ◽  
J. R. Batra ◽  
...  

Crossbreeding parameters (line additive, dominance and additive × additive epistatic effects for individual and for maternal performance) on growth traits of females from a crossbreeding experiment between Holstein-based (HS) and Ayrshire-based (AS) lines were estimated by individual animal models, incorporating all known additive genetic relationships among animals, through restricted maximum likelihood and mixed-model methodologies. The growth traits [asymptotic weight (A), rate parameter (k), inflection parameter (m), average lifetime absolute growth rate (AGR), average lifetime absolute maturing rate (AMR) and average lifetime relative growth rate (RGR)] were estimated by fitting the Richards function to the observed growth curve of 3076 individuals. The statistical model included the random effect of the animal breeding value and the fixed effects of genetic group and station–year–season of birth. Results indicated that the HS exceeded (P < 0.001) the AS in additive effects for individual performance for both A and AGR. The HS exceeded (P < 0.05) the AS in additive effects for maternal performance for A. Individual heterosis was positive for A (P < 0.001) and for AGR (P < 0.01). Maternal heterosis was negative for A (P < 0.05) and positive for AMR (P < 0.05). Total heterosis (TH) had positive effects on both AGR and AMR (P < 0.05). Heterosis retained in advanced crossbred generations was not significant (P > 0.05) for any of the studied traits. The results suggest that crossbreeding designed to exploit TH can alter the shape of the growth curve of dairy cattle. Key words: Crossbreeding, dairy cattle, growth curve


2019 ◽  
Vol 57 ◽  
pp. 60-67
Author(s):  
G. D. Іlyashenko

Dairy cattle breeding is one of the leading livestock sectors whose purpose is to ensure the production of high quality dairy raw materials in volumes meeting the scientifically grounded standards of state food security and expanding the export potential of the agrarian sector. The purpose of our research was to study the status and prospects of dairy cattle breeding in the Kirovograd region. Material and methods of research. The research was carried out on the basis of the electronic database of breeding goals (including 2312 cows), official statistics and estimates of cattle of various breeds that are involved in the production of dairy direction in the breeding farms of the Kirovograd region. The analysis used zootechnical and statistical methods. The calculations were carried out using the software package "STATISTICA-6,1" Results. According to the research (2001–2018), the cattle population in the Kirovograd oblast decreased by a factor of 2.6. Thus, as of January 1, 2018, its number constituted 96.3 thousand heads in all categories of farms, 53.1 thousand of them were cows, the number of which also decreased by 2.4 times. Specific gravity of cattle population of farms remains significant and makes up 72.7%, and 80.6% in the livestock of cows. The largest number of cows of agricultural enterprises declined significantly. Thus, as of January 1, 2018, their number was 10.3 thousand goals, which is 4.7 times less than in the same period of 2001. In the households there is also a tendency for a permanent reduction of cows, the difference is, respectively, 37.0 thousand heads or 46.4% The development of dairy cattle breeding is characterized by two opposite tendencies: reduction of livestock of cows and increase of their productivity. Thus, in agricultural enterprises in 2010, compared to 2000, hopes per cow increased by 2.5 times, in all categories of farms by 1.8 times. In 2017, the increase in dairy costs in agricultural enterprises compared to 2010 amounted to 60.0% in farms of all categories 12.2%. The researches found that in the agricultural enterprises of the oblast as of January 1, 2018 there are 26256 head of cattle, including 10281 cows. The breeding part of the existing cows is 3.013 heads, 29.3% of the total number located in 10 breeding farms. The analysis of the genealogy structure showed that the experimental population of cows belongs to 18 lines and related groups of which the most numerous Chifa 1427381 – 20.4%, Starbuck 352790 – 20.1%, Henev 1629391 – 18.6% , Eleusis 1491007 – 11.2%, Family 267150 – 10.8%. Among the indicated lines, the lowest level of milk productivity was first-born cows. The 1491007, the milk of milk for 305 days of lactation was 4466 ± 99.8 kg, and the milk fat was 168.2 ± 6.5 kg. Analogues l Starbak 352779 was characterized by the highest milk productivity, its level was 5696 + 98.8 kg and 224.9 ± 9.7 kg, respectively. The difference in stomach was 1230 ± 140.4 kg (td = 10.2) and at the release of milk fat 56.7 ± 5.28 kg (td = 10.2) at P < 0.001. However, the latter were markedly less service life (125 against 168 days) and logically higher reproduction rate compared to other lines. An analysis of the intensity of the formation of live weight of young animals has been established for its highest growth in heifers of controlled herds in the period from 9 to 12 months. Thus, in animals of Ukrainian red breed, the growth rate of live weight during this period was 75 kg, Ukrainian red-shrimp 61 kg, Ukrainian black-and-white 73 kg, Holstein 76 kg. Accordingly, during this period, the average daily gain of live weight of young breeds of these breeds was 833 g; 678 g; 811 g, 835 g. The sharp fluctuations of average daily increments during growing periods, first of all, testify to the unequal conditions of growing and feeding young animals than the breed differences. In general, as a result of the analysis of the formation of live weight of heifers, a significant level of phenotypic variability was observed, which confirms sufficient genetic resources and preconditions for selection on the given sign. Therefore, proceeding from the above, in the long run, selection work for breeding improvement of cattle breeding farms of the Kirovograd region should be conducted in accordance with certain promising directions according to groups of breeds. Conclusions. A very important factor in the growth of milk production in the Kirovograd region is high-yield pedigree cattle. The main task on the way of bringing breeding cases in dairy farming to the modern level is the introduction of computer breeding records in breeding farms. This will allow to estimate in the near future bulls-pedigrees, which were used in the past in these farms, to allocate among them complex improvers for precisely the specific conditions and maximally attract them for reproduction. On the other hand, a reliable clogging of poor quality in the genetic sense of sperm production, which leads to negative consequences, will be posed. When establishing the assessment of the breeding value of bulls and developing a single plan of breeding and breeding work in the region, one can proceed to the next step of improving breeding and breeding business, introducing a progressive method of raising the breeding value of animals of large-scale breeding. As a result, the profit from the breeding of highly productive animals, well adapted to specific conditions, will significantly exceed the costs. At the same time, the proposed measures will allow the breeding business to be brought up to the modern world level and stimulate highly productive cattle breeding.


Author(s):  
T. Pook ◽  
L. Büttgen ◽  
A. Ganesan ◽  
N.T. Ha ◽  
H. Simianer

ABSTRACTSelective breeding is a continued element of both crop and livestock breeding since early prehistory. In this work, we are proposing a new web-based simulation framework (“MoBPSweb”) that is combining a unified language to describe breeding programs with the simulation software MoBPS, standing for ‘Modular Breeding Program Simulator’. Thereby, MoBPSweb is providing a flexible environment to enter, simulate, evaluate and compare breeding programs. Inputs can be provided via modules ranging from a Vis.js-based flash environment for “drawing” the breeding program to a variety of modules to provide phenotype information, economic parameters and other relevant information. Similarly, results of the simulation study can be extracted and compared to other scenarios via output modules (e.g. observed phenotypes, accuracy of breeding value estimation, inbreeding rates). Usability of the framework is showcased along a toy example of a dairy cattle breeding program on farm level, with comparing scenarios differing in implemented breeding value estimation, selection index and selection intensity being considered. Comparisons are made considering both short and long-term effects of the different scenarios in terms of genomic gains, rates of inbreeding and the accuracy of the breeding value estimation. Lastly, general applicability of the MoBPSweb framework and the general potential for simulation studies for genetics and in particular in breeding are discussed.


Sign in / Sign up

Export Citation Format

Share Document