scholarly journals THE GENEALOGY RELATIONSHIP OF HOLSTEIN BULLS IN UKRAINE

2018 ◽  
Vol 51 ◽  
pp. 78-83
Author(s):  
T. A. Kruglyak

The grades of genealogy relationship of bulls with the head of bloodlines are not equivalent in each genealogical formation and are stipulated by the number of animals (branching) in bloodline, their diversity, distance from the head of bloodlines and system of selection. Thus, the coefficients of kinship of bulls, descendants of which have 5 and more ranks in genealogy: 1427381 Chief (n = 79), 1650414 Valiant (n = 10) and Elevation 1491007 (n = 64) with the ancestors of these bloodlines were 5,67; 8,81 and 8,37% respectively. Slight higher coefficients of genealogical kinship of bulls with successors of Chief bloodlines – Blackstar 1929410 – by 2,28 (7,35%) and Belwood 2103297– by 1,67% (6,37%), due to the use of the last ones in the pedigrees of these bulls on the maternal side. Significantly higher coefficientsof genealogical kinship of bulls of Starbuck 352790 bloodlines (n = 112) were with the ancestor and successors of this bloodline. Thus, the coefficient of kinship of bulls of Starbuck bloodline with their ancestor was 13,4% and with successors Aerostar 383622 – 16,9%, Mtoto 6001001962 – 9,0%, Storm 6820564– 10,9% and Shottle 598172 – 9,8%. It was found that the highest coefficient of genealogical kinship was at the bulls of new lines and related groups Marshal 2290977 – 30,5; Toystory 60372887 – 18,5; Buckeye 130588960 – 14,8; Goldwyn 10705608 – 19,1; Shottle 598172 – 25,1%. This is because the offspring were at 1-2 generations from their founders. The high interline genealogical kinship of bulls was revealed. Thus, the coefficient of genealogical kinship of bulls of all the bloodlines with progenitor of Starbuck 352790 bloodlines was 0,96-13,4 and with his son Aerostar 383622 – 2,9-16,9%. Average degrees of kinship of bulls of all the population with these leaders of the breed were also quite high (8,16 and 11,42% respectively). This shows the great saturation of pedigree of all the Holstein bulls bygenes of Starbuck 352790, Aerostar 383622 and Elevation 1491007, which complicates scheduling the breeding selection even at crossing bloodlines because ancestors of the same bulls of several lines are in pedigree of animals of each bloodline. This explains increasing inbred cows in the latest generation of Ukrainian Black-and-White Dairy cattle to 71,3-91,3%. Perhaps for restraining growth of the number of inbred cows, US experts prolong duration of hereditary qualities transmissionof a founder in generations by creating so-called "inbred" lines. To do this, for carefully selected mothers of bulls with high levels of economic useful traits (yield, fat and protein contents) of some line are selected bull-leaders of the same line with similar breeding values (homogeneous selection). Using inbreeding of different degrees from remote (V-V) and moderate degrees (III-IV, IV-IV) to close one (II-II, II-III, III-III), inbred animals are obtained and bred "in itself" again (integrated inbreeding). Probability of obtaining larger number of animals with hereditary traits of ancestor’s performance increases. So, 30 (8,77%) of 342 bulls used in Ukraine, are obtained in this way and bulls of only this line used as fathers in 4 ranks of their pedigree. Use of moderate and remote levels of inbreeding on ancestorsof lines maintains high genealogical kinship of animals at their distance in generation and accumulation of valuable traits in populations which are inherent for ancestorsof lines. Share of inbred bulls in all the lines is quite high – 80,7%. On average, 15 bulls were obtained as a result of the close degree of inbreeding in the population (II-II, II-III). The number of moderate levels of inbreeding (II-IV, III-IV, IV-IV and IV-V) at obtaining these bulls was 244 and remote one (V-V and above) – 195. In addition, 116 fathers and 59 mothers received as a result of various degrees of inbreedingwere foundin the pedigrees of the bulls. Among them 15 animals (8,57%) were as a result of close degree of inbreeding, 127 (72,6%) – moderate and 33 (18,8%) – remote; it also forms the genealogical relationship between bulls of various lines. Thus, the rate of genealogical kinship characterizes the intensity of using bull-leaders, ancestors of bloodlines and their successors for breeding stock, from both paternal and maternal sides of genealogy and genealogical relations between some bloodlines, it is important to consider while forming further genealogical structure of the breed and breeding selection as at breeding herds, so at production ones of domestic dairy cattle.

Author(s):  
O. V. Gorelik ◽  
N. A. Fedoseeva ◽  
A. S. Gorelik ◽  
E. V. Koksharov

In the last few decades the improvement of domestic dairy cattle was due to the widespread use of the gene pool of the best world breed such as Holstein. As a result of crossbreeding the breeding stock of the domestic Black-and-White breed with the sires of Holstein breed in different regions of the country a population of crossbreds has been created. The purpose of the work was to study the age dynamics of the live weight of replacement heifers depending on the paternal origin and the correlation between the indicators for the growth periods. The daughters of different sires have a difference in their live weight at the first insemination. The live weight of more than 400 kg was obtained from replacement heifers obtained from the sires Saber, Decaro and Baquero. The daughters of the sires Gatedenser, Bentley and Alta Ciara in live weight were inferior to their herdmates by 2,7–9,3 kg or by 0,7–2,8 % (P ≥ 0,05). The bulk of the replacement heifers are inseminated at the age of 13 months and only the daughters of the sire Alta Ciara are inseminated at the age of 14,1 months with a live weight of 396,7 kg. Despite the almost identical live weight of heifers at birth they differed from each other in the process of rearing. It has been established that the live weight at birth is not an indicator for assessing the further growth of replacement young animals. At 6 months of age the correlation of live weight at the age of 6 months and at the first insemination was positive and ranges from 0,01 (daughters of the sire Baquero) to 0,55 (daughters of the sire Decaro). Selection of heifers at the age of 6 months by their live weight allows us to choose the best and provide the opportunity to inseminate them at the age of 12–13 months with the organization of intensive rearing.


2018 ◽  
Vol 51 ◽  
pp. 140-147 ◽  
Author(s):  
A. Ye. Pochukalin ◽  
O. V. Rizun ◽  
S. V. Priyma

The genealogical structure of Ukrainian Red-and-White Dairy cattle has been represented by 12 tested and approved farm bloodlines, ancestors of which are Holstein bulls of red colour (Improver 333471, Hanover 1629391, Regal 352882, Nahit 300502, Inhancer 343514, Cavalier 1620273), Montbeliarde (Supreme 33470, Mayerdel 1599075, Dynamic 359742, Dairymen 1672325, Shevrey 6241) and Ayrshire (Don Juan 79601) breeds. Selection process ensures constant movement of lines and inheritance of some lines moves to historical and statistical work and is used for analysing the successful selection and the best combination, whereas, the other ones improve genetic value of economically useful traits of productivity in the next generations and, therefore, they are progressing and developing. Qualitative features of related groups by the breeding traits are a basis on which we should concentrate all the range of selection and breeding work at each stage of breed improvement because a line and a breed, in the classical sense, are inseparable concepts of a large conglomerate of a population, which has been created by many scientists and practitioners.  The aim of this work was to analyse the current state of genealogical structure of Ukrainian Red-and-White Dairy breed for the breeding stock and their belonging to breeds and lines. The materials of research for characteristics and analysis of genealogical structure of Ukrainian Red-and-White Dairy cattle were breeding accounting data on the form №7-mol. In total the data for 74 breeding farms of 15 regions of Ukraine were used. Belonging to breeds, lines and data for assess by origin and progeny were determined on the basis of SUMS "Orsek", Institute of Animal Breeding and Genetics nd. a. M.V. Zubets of National Academy of Agrarian Science of Ukraine. The availability of frozen semen of the Ukrainian Red-and-White Dairy bulls admitted to reproduce breeding stock was determined according to the annual catalogues for 2015 and 2016.2016. Modern genealogical structure of the breeding stock is formed due, in addition to Ukrainian Red-and-White Dairy breed, Red Holstein, Jersey, Montbeliarde and Simmental breeds. The total number of females is 48,279 animals, including 24,264 cows and 24,015 heifers originating from 375 bulls. The share of Simmental bulls involved in the selection was 11% (42) with the number of 881 animals. The breeding stock from Holstein bulls (207) is 82%, whereas, the share of 101 bulls of Ukrainian Red-and-White Dairy breed is only 15%. Modern genealogical structure of the breeding stock is formed due, in addition to Ukrainian Red-and-White Dairy breed, Red Holstein, Jersey, Montbeliarde and Simmental breeds. The total number of females is 48279 animals, including 24264 cows and 24015 heifers originating from 375 bulls. The share of Simmental bulls involved in the selection was 11% (42) with the number of 881 animals. The breeding stock from Holstein bulls (207) is 82%, whereas, the share of 101 bulls of Ukrainian Red-and-White Dairy breed is only 15%. Genealogical structure of breeding stock of Ukrainian Red-and-White Dairy breed has been represented by 15 bloodlines. The fewest (71 animals) was obtained from three bulls Magnet 1560362, Majority 1599069 and Maximus 297414. The 10%-share (4712 animals from 57 bulls) from the total number was genealogical structure of six approved farm bloodlines of the Ukrainian breed. For breeding evaluation of origin (pedigree index) 17 Holstein bulls had the average value – +27.6, including seven bulls with negative PI-595 and 10 bulls with positive PI + 463.5. For bulls of Simmental and native breeds, the indices were 6 (-122), 2 (+264), 4 (-315) and 12 (+587.8), 1 (-264) 11 (665) respectively. Discrepancy (2 of 35 investigated bulls) with the minimum requirements (30 first-calf heifers in 4 herds) concerning the evaluation of bulls by progeny makes impossible to obtain objective information about breeding value of bull. In our opinion, the factors which, can make a difference in the genealogical structure of Ukrainian Red-and-White Dairy cattle are to increase the share of bloodlines of the native breed through catalogue of admitted bulls to reproduce breeding stock, which is compiled by the materials of pedigree enterprise of Ukraine. Based on materials of 2015, during the mating period 59 bulls of 15 bloodlines were involved, including 38 approved bulls which share of sperm was 84%. In 2016, the available frozen semen of bulls of the native breed decreased by 674.5 thousand doses which was 81% compared to presented one in 2015. Conclusions. Current genealogy of Ukrainian Red-and-White Dairy cattle has the ramified system represented 42 Simmental bulls of 15 bloodlines, 207 Holstein bulls of 19 bloodlines, 101 native bulls of 15 bloodlines and two Jersey and Montbeliarde bulls. In modern realities of selection and breeding work, concern is widely use of Holstein sires in the reproduction of breeding stock of Ukrainian Red-and-White Dairy that each year minimizes the share (now about 10%) in the selection of approved bloodlines and "genetic identity of native breed". The perspective of involving bulls and with it the widespread use of the method of breeding by bloodlines in Ukrainian Red-and-White Dairy cattle is too illusory, whereas every year the availability of semen of the admitted bulls in sperm banks of Ukraine decreases (only the last year by 81%), and inability (with requirements) for the evaluation by progeny of those bulls which have already had pedigree index.


2003 ◽  
Vol 46 (2) ◽  
pp. 155-165
Author(s):  
D. Hinrichs ◽  
T. O. Kuhlmann ◽  
E. Stamer ◽  
E. Kalm

Abstract. Title of the paper: Genetic analysis of claw measurements from the performance test of young bulls The present study deals with the analysis of the claw measurements length of dorsal wall, length of heel, high of heel, diagonal, angle of dorsal wall and hardness of claw horn from the performance test of young bulls. Data collection take place at one fore leg and one hind leg from 798 young German Holstein bulls (black and white, red and white) and 89 young Angler bulls. The analysis of the systematic fixed effects was followed by the estimation of genetic parameters. A breeding value estimation was done with some of the claw traits and rank correlation for the breeding values of the claw traits and some official exterieur breeding values and the length of productive life were calculated. Heritabilities ranked from 0.00 (hardness of claw horn, upper point of measurement of hind leg) to 0.45 (diagonal of the foreleg). Genetic correlation between fore leg and hind leg vary between 0.14 and 0.99. Rank correlation of the claw trait breeding values ranked from –0.65 to 0.64. Rank correlation between official breeding values and claw trait breeding values vary from –0.27 to 0.37.


2018 ◽  
Vol 30 (1) ◽  
pp. 199
Author(s):  
A. A. Sermyagin ◽  
A. F. Conte ◽  
V. V. Volkova ◽  
O. S. Romanenkova ◽  
A. A. Kharzhau ◽  
...  

The aim of genetic improvement in cattle breeding is to create animals, which are characterised by high economic efficiency while maintaining the high breeding values for health and reproduction traits. In Russia dairy cattle industry the integrated approaches based on application of genomic methods for cows’ fertility and health traits along with milk production are being developed. However, their efficiency depends largely on the ability for multiple replicating outstanding individuals by embryo transfer. Therefore, the target of our research was to develop a strategy for the integrated genetic improvements of fertility and udder health traits towards the production of embryos with high estimated breeding values (EBV). We analysed the culling factors of more than 23,400 Black-and-White and Holstein cows of the Moscow region cattle population. Using the genotyping procedure by Illumina Bovine SNP50 BeadChip (Illumina Inc., San Diego, CA, USA), the regional training group consisted of 401 proven bulls and 60 pre-selected cows was formed. After the quality check based on Plink 1.90, we selected 39,631 single nucleotide polymorphisms for the analysis. The GBLUP methodology was used to calculate genomic EBV (GEBV). The cows were additionally tested by PCR or PCR-RFLP (restricted fragment length polymorphism) for LoF mutations in the genes FANCI, APAF1, SMC2, GART, ITGB2, SLC35A3, and APOB, associated with fertility haplotypes HH0, HH1, HH34, HH4, HHB, HHC, and HCD, respectively. The evaluation of genetic variances and EBV for days open (DO), breeding per conception (BC), calving ease (CE), somatic cell score (SCS), milk yield (MY), fat yield (FY), and protein yield (PY) was carried out using the BLUPF90 family of programs. Cows’ culling rate for reproductive traits was 21% and for udder diseases was 8%. The genetic correlations, rg, between SCS and cows’ fertility traits were rg = 0.132 for BC, rg = 0.067 for DO, and rg = –0.056 for CE that can be used as an indicator for the monitoring reproductive disorders at the different stages of lactation. The frequencies of fertility haplotypes’ carriers among the potential donor dams were 6.6, 1.1, 8.8, 0.0, 1.1, 0.0, and 4.4% for HH0, HH1, HH3, HH4, HHB, HHC, and HCD, respectively. Based on EBV and carrier status for LoF mutations, we selected 46 dams and 28 sires to produce embryos with high GEBV for MY (+633, ..., +884 kg), FY (+26 kg), PY (+18 kg), and SCS (106 points) and higher as population average GEBV for fertility and udder health traits. Genome-wide association study analysis by the reliability of Bonferroni correction test (P < 1.2 × 10−6) showed the presence of quantitative trait loci on BTA1, BTA5, BTA9, BTA11, BTA12, BTA27, and BTX. Our results will be used to construct Russian fitness index for dairy cattle and for implementing embryo production technology into the Russian breeding system. Research supported by the Russian Science Foundation within Project no. 15-16-00020.


2017 ◽  
Vol 53 ◽  
pp. 115-119
Author(s):  
A. V. Dymchuk ◽  
O. I. Lyubynskyy

The studies of the dynamics results of body weight, absolute and daily average, relative increases averaging bulls of Ukrainian black-and-white and Ukrainian red-and-white dairy cattle. Researches are conducted in the conditions of POSP «Napadivske» Kalyinivka district of the Vinnytsya area after materials of primary pedigree account. In an economy use the whole-year of the same type feeding. In the structure of ration 40% make the concentrated sterns and also high-quality silage and soilage. Average daily increases of bulls for period of age to realization for a slaughter made over 1000 grammes. The dynamics of growth of living mass, absolute, average daily and relative increases of bulls, is analysed Ukrainian black-and-white and Ukrainian red-and-white dairy cattle. Living mass and weight gain researches of age to 12-monthly age with an interval in 3 months after the generally accepted methods. Materials of researches are worked out the methods of mathematical statistics with the use of programmatic package of Statistica 8.0. Living mass of bulls of the second group at birth made 36,3 kg, that anymore on 0,8 kg by comparison to new-born bulls of the first group. In all next periods living mass of animals of the second group was greater as compared to the animals of the same age of the first. In 3 months advantage made 1,7 kg, in 6 months – 4,6 kg (P>0,95), in 9 months – 8,8 kg (P>0,95), in 12 months – 12,5 kg (P>0,99). Difference of absolute increases of bulls of the second group above the bulls of the same age of the first of age to to 3-monthly age made 0,8 kg in behalf of animals of the second group. In a period 3-6 months a difference is after this index between the first and second groups made 2,9 kg in behalf of the last. In periods 6-9 and reliable advantage of animals of the second group is 9-12 months set above the bulls of the same age of the first on 4,1 kg (P>0,95) and 3,7 kg (P>0,95) accordingly. In a period of age to 18-monthly age absolute increases of bulls of the second group were greater by comparison to bulls first on 12,5 kg (R>0,99). Average daily increases of bulls of the second group of age to 3-monthly age made 763,0 grammes, that anymore on 8,9 grammes by comparison to bulls of the first group. In periods 3-6 months the average daily increases of animals of the second group prevailed the bulls of the same age of the first on 32,6 grammes. In a period 6-9 months the average daily increases of animals of the second group were made by 1045,9 grammes, that for certain anymore on 45,9 grammes (P>0,95) by comparison to the bulls of the same age of the first. Maximal increases of bulls were in a period 9-12 months and made 1210,4 grammes in the animals of the second group and 1168,9 grammes – for the bulls of the same age of the first, that for certain anymore on 41,5 grammes (P>0,95). In a period of age to 12-monthly age the average daily increases of bulls of the second group were made by 970,6 grammes, that was for certain anymore on 31,8 grammes (R>0,99) by comparison to the bulls of the same age of the first group. Relative increases of bulls of both groups were high. From birth to 3-monthly age greater increases had bulls of the first group – 97,8%, and in periods 3-6, 6-9 and 9-12 months greater were increases of bulls of the same age of the second group – 56,4; 40,1 and 32,4% accordingly. For all probed periods of reliable advantage it is not discovered between the compared groups. It is set researches, that at the identical terms of feeding and maintenance more rapid bulls grow Ukrainian red-and-white dairy cattle. In all age-old periods they prevailed the bulls of the same age of the Ukrainian black-and-white dairy cattle, in a that number, beginning from 9-monthly age, advantage was reliable (P>0,95–0,99). Average daily increases of bulls of two breeds were the least in a period of age to to 3-monthly age – 754,1-763,0 grammes, and most in a period 9-12 months – 1168,9–1210,4 grammes.


2016 ◽  
Vol 52 ◽  
pp. 6-12 ◽  
Author(s):  
M. V. Gladiy ◽  
G. S. Kovalenko ◽  
S. V. Priyma ◽  
G. A. Holyosa ◽  
A. V. Tuchyk ◽  
...  

The main goal of dairy breeds selection should be improving breeding and productive qualities of animals under modern conditions. The majority of farms, using native breeds to produce milk, has created optimal conditions for keeping and feeding, selection and matching, growing of replacements etc. Further improvement of created native dairy breeds for economically useful traits occurs at total use of purebred Holstein bulls (semen) of foreign selection. In order to realistically assess milk productivity (milk yield, fat content in milk and fat yield) of Ukrainian Black-and-White and Red-and-White Dairy cows should be conducted a comparative analysis of Holstein cows under the same conditions of feeding and keeping. It was established that Ukrainian Red-and-White Dairy cows were characterized by the highest milk yields for 305 days of all lactations, taken into account, the among three investigated breeds. Their milk yield during the first lactation was 5933 kg of milk, during the second – 6393 kg, the third – 6391 kg and during higher lactation – 6650 kg. Ukrainian Black-and-White Dairy cows were second by milk yield (except for the second lactation), during the first lactation – 5932 kg of milk, the third – 6462 kg and higher – 6541 kg, and Holstein cows were third, during the first lactation – 5794 kg of milk, the second – 6381 kg, the third – 6335 kg and higher – 6469 kg. The fat content was almost the same and varied within 3.49-3.58% in milk of Ukrainian Red-and-White Dairy cattle, 3.50-3.60% in milk of Ukrainian Black-and-White Dairy cattle and 3.50-3.56% in Holsteins’ milk. The difference between the breeds was within 0.01-0.04%. All the investigated breeds had predominance in fat yield for three lactations over standards of these breeds: Ukrainian Red-and-White Dairy cows from 75.1 to 93.4 kg, Ukrainian Black-and-White Dairy cows – 75.1-89.0 kg respectively and Holstein cows – 41.9-60.2 kg. It was found different level of positive correlation between milk yield and fat yield in all the cases and high correlation (r = 0.604-0.921, P < 0.001) in five cases (41.7%) Negative correlation coefficients indicate that selection of animals to higher milk yield in the herd will decrease the second trait – fat content in milk. Positive and highly significant correlation between milk yield and fat yield indicates that selection of cows in the herd to higher milk yields will increase fat yield. It was revealed that bulls were among the factors impacted the milk productivity (milk yield, fat content, fat yield) of three investigated breeds. So, the force (η²x) of father’s impact on milk yield was15.4-47.9%, fat content – 22.0-43.4% and fat yield – 14.9-47.7% taking into account a lactation and a breed. The force of lines impact (η²x) was second; it was on milk yield 6.1-24.5%, fat content – 4.1-17.1 and fat yield – 5.8-23.5%. The force of breeds impact (η²x) was last; it was on milk yield 0.3-2.9%, fat content – 0.2-0.3% and fat yield – 0.6-2.7%. So, the comparative studies of milk productivity of Ukrainian Red-and-White and Black-and-White Dairy cattle with Holsteins indicate that under similar conditions of feeding and keeping, these native breeds can compete with Holstein cattle. The milk yield for 305 days of higher lactation was 6650 kg of milk in Ukrainian Red-and-White Dairy cows, 6541 kg in Ukrainian Black-and-White Dairy cows and 6469 kg in Holsteins. It was found the inverse correlation r = -0.025-0.316 between milk yield and fat content in milk in most cases. Selection and matching of animals in the herd should be carried out simultaneously on these traits. It was found positive repeatability of milk yields between the first and second, the third and higher lactations (rs = 0.036-0.741), indicating the reliability of forecasting increase in milk productivity during the next lactations in all herd. Bulls have the greatest impact (η²x) on milk productivity among the factors taken into account: milk yield – 15.4-47.9%, fat content in milk – 22.0-43.4% and fat yield – 14.9-47.7%.


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 694
Author(s):  
Michaela Gibson ◽  
Rebecca Hickson ◽  
Penny Back ◽  
Keren Dittmer ◽  
Nicola Schreurs ◽  
...  

In cattle, limited data have been reported about the relationship between live weight, bone size, and strength and how this relationship can be altered by factors such as sex and age. The aim of this study was to describe the relationship of peripheral quantitative computed tomography (pQCT)-derived parameters of bone strength and morphology with live weight, age and sex in beef-cross-dairy cattle. All animals were weighed the day before slaughter. The metacarpus and humerus were collected at slaughter and scanned at the mid-diaphysis using pQCT. Live weight was the primary explanatory variable for bone size and strength in all cohorts. However, the effect of age was significant, such that magnitude of response to liveweight was less in the 24-month-old cohort. Sex was significant within cohorts in that bulls had a shorter metacarpus than steers and heifers had a shorter metacarpus than steers at age of slaughter.


1990 ◽  
Vol 57 (1) ◽  
pp. 53-62 ◽  
Author(s):  
Anne-Marie Bech ◽  
K. Rotvig Kristiansen

SummaryIn milk samples from 549 cows of the breeds Danish Jersey, Red Danish Dairy Cattle (RDM), and Black and White Danish Dairy Cattle (SDM) the genetic polymorphisms of the αs1, β and K-cascin and β-lactoglobulin (β-Lg) loci were determined by isoelectric focusing in agarose gels. The results of the screening were comparcd with results obtained by Larsen & Thymann (1966). In addition, the genetic linkage of the three casein loci was studied, and the association between milk protein genotypes and yields in first and second lactations of milk, fat and protein were investigated.The distribution of genotypes of all four milk protein Systems was different from breed to breed.For Jersey cows, significant differences in the gene frequencies from the results of the 1966 investigation were found for αs1 and K-casein and β-Lg. For SDM cows a change in the K-casein frequency had occurred whereas for RDM cows no changes were found.Linkage between some of the casein loci was found within ail three breeds. For the RDM breed the possible linkage between αs1-casein and the other caseins could not be tested bccause nearly ail thc cows were homozygous for the αs1-cascin-B genotypes.β-Casein genotypes were associated with yield parameters in ail breeds. The A2A2 genotype of this protein gave higher yields of milk, fat, and protein in the second lactation than thc A1A1 genotype.


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