CC BY
8
Ukrainian Journal of Ecology
Ukrainian Journal ofEcology, 2021, 11(3), 353-359, doi: 10.15421/2021_183
ORIGINAL ARTICLE
Influence of the fixed "father" factor on the protein content in mil k and the yield of milk protein in cattle
A.P. Palii1*, T.L. Osipenko2, V.A. Chigiryov3, I.Y. Gurko3, R.V. Petrov4, A.V. Berezovsky4,
O.A. Khitska5, S.V. Furman6, D.V. Lisohurska6, O.V. Lisohurska6
1Kharkiv Petro Vasylenko National Technical University of Agriculture, 44 Alchevskih St., Kharkiv, 61002,
Ukraine
2Institute of Animal Science NAAS of Ukraine, 1-А Livestock breeders St., Kharkiv, 61026, Ukraine
3Odessa State Agrarian University, 13 Panteleimonovskaya St., Odessa, 65012, Ukraine
4Sumy National Agrarian University, 160 Gerasim Kondratiev St., Sumy, 40021, Ukraine
5Bila Tserkva National Agrarian University, 8/1 p. Soborna, Bila Tserkva, Kiev region, 09117, Ukraine
6Polissia National University, 7 Stary Blvd, Zhytomyr, 10008, Ukraine Corresponding author E-mail: [email protected]
Received: 29.05.2021. Accepted: 01.07.2021.
Increased productivity in cattle is performed by using the methods of genetics and breeding. Currently, one of the promising directions for increasing the milk productivity and manufacturability of domesticated cattle is the use of the genetic potential of breeding bulls. During the research, the results of a one-way analysis of variance of the influence of the "father" factor on productive indicators were analyzed. The factor "father" was used as the analyzed factor, and the content of protein in milk and the yield of milk protein were used as dependent factors. For each fixed factor, standard indicators of protein content in milk and milk protein yield have been determined. Also, the degree of influence of the investigated factors under their action, both independently and together with other conditioning factors, on the protein content and the yield of milk protein was determined. The determination of the simultaneous influence of several factors on the effective indicator was carried out using a two-way analysis of variance. It was found that the degree of influence of bulls on the protein content in daughters' milk was 7.9%, on the yield of milk protein-19.6% with high confidence levels (P>0.999). Among the factors studied, the most strongly influencing pair was "calving number-father". This combination of factors also turned out to be one of the most significant against the background of the final comparative assessment of all investigated ones in the work. It is essential that the "father" factor, as an independent factor, has a lower power of influence on the protein content in milk than when interacting with the "calving number" factor. Thus, the factor "father" causes 7.9% of the protein content in the milk of daughters, and in combination with the factor "calving number" the influence is 5.4% greater. At the same time, such a pattern is not observed in the yield of milk protein. In this case, the opposite trend is observed: the "father" as an independent factor has a higher influence compared to the options of its interaction with other studied factors. Thus, the value of the bull-producer is one of the main factors that determine the protein content in milk and milk protein yield, and one of the most important evaluation criteria.
Keywords: Cattle, milk, protein, milk protein, lactation, degree of influence, confidence level, bull-producer.
Introduction
At this time in dairy cattle breeding, there are still many problems, among which the following are the main ones: obtaining high milk yield; providing livestock with appropriate conditions in which their genetic potential can manifest; rearing stock with live weight by the breed standard (Krugliak & Krugliak, 2020; Paliy, 2016). The high level of industrial use of animals is the most important selection and genetic trait, which has a hereditary basis and depends on both the mother and the father. It has been established that even within the same herd, there is a significant number of bull daughters, which with a high degree of reliability differ in terms of use in the herd (Palii et al., 2021a).
Increasing the productivity of cattle is carried out using the methods of genetics and selection. Currently, one of the promising directions for increasing the milk productivity and manufacturability of domesticated cattle is the use of the genetic potential of breeding bulls in selection (Prudov & Dunin, 2005). Also, for any breed, it has been determined that their potential is increased mainly through the use of breeding bulls. At the same time, the phenotypic specificities of the half-sisters groups after the father and animals of different linear affiliation to a certain degree (sometimes significantly) change in the chronology of different years of economic use in different herds and climatic conditions (Polupan & Gavrilenko, 2008).
In this regard, in dairy farming, special attention is paid to the assessment and selection of bulls by the quality of the offspring. Most authors have found that genetic improvement in dairy cattle depends on the heredity of the breed leader bull (Kuznetsov, 2002; Selionova & Kovaleva, 2015; Zubets et al., 1997). Several methods are used to evaluate the bull by the quality of the offspring: comparison of the performance of daughters with peers, the average productivity of the herd or breed, the current breed standard, the best linear unbiased forecast (BLUP), "father's model", "animal model", breeding indices are calculated (Danshin, 2008; Krasota et al., 2006). In Ukraine, the assessment of producers involves the use of the method of comparing daughters with peers, as well as determining the estimated breeding value. Scientists have found that only a small part of Holstein bulls simultaneously combine breeding value by two characteristics (milk yield - fat content in milk, milk yield - protein content in milk) and even less - by three traits (milk yield-fat-protein).
In the works of Korshun & Klimov (2016) and Palii et al., (2020a), it has been found that when studying the influence of various factors on the longevity indicators of dairy cattle, among genetic factors, the factor of father's heredity has the greatest influence on productive longevity. Also, the researcher Titova (2017) has found that the father's genotype had a significant effect on productive longevity and life-long milk yield of cows-37.7% and 30.3%, respectively. The longest period of productive use and the highest lifetime milk yield were characteristic of the descendants of purebred black-and-white bulls in comparison with hybrid bulls -producers of the Holstein breed. Until now, in the selection of dairy cattle, information on the milk productivity of their female ancestors has been used as the main criterion for the selection of sire bulls (Titova, 2016). The identification of producers that increase the mass fraction of protein in daughters' milk and their widespread use largely determines the intensity of improving domestic cattle in terms of protein-milk content (Lazarenko et al., 2004; Osipenko et al., 2018).
An important selection method for improving the herd is the use of the best breeding bulls, whose daughters, according to the blocks of milk productivity and reproductive ability, should be as close as possible to the parameters of animals of the desired type. The smaller the difference between the two, the more profitable the use of one or another producer on the farm will be (Kochuk-Yashchenko & Kucher, 2020; Palii et al., 2020b).
In studies by Shulyar et al. (2020), it has been found that when analyzing three factors of influence (the conditional part of blood by the Holstein breed, father, line), in cows-first-calf heifers of the Ukrainian black-and-white dairy breed, it was of paternal origin and was: milk yield for 305 days of lactation (19.0%, P<0.001), fat content in milk (2.5%, P<0.001), amount of milk fat (13.0%, P<0.001), protein content in milk (6.5%, P<0.001), the amount of milk protein (20.8%, P<0.001), and the total production of milk fat and protein (16.4%, P<0.001).
Valuable are bulls whose daughters have a positive and slightly negative correlation between milk yield and fat, milk yield and protein, as well as bulls, in whose offspring high positive values of the correlation coefficient between fat and protein are revealed. Thus, the selection and widespread use of sires, in the offspring of which a positive correlation between milk yield and fat content, between milk yield and protein content, will help to quickly overcome the undesirable negative relationship between these traits.
Materials and Methods
During the research, the results of a one-way analysis of variance of the influence of the "father" factor on productive indicators were analyzed. The factor "father" was used as the analyzed factor, and the content of protein in milk and the yield of milk protein were used as dependent factors. The analysis was carried out using the procedure of the general linear model (General Linear- GLM General Factorial) of the computer standard package of statistical programs SPSS 16.0. For each fixed factor studied by us, the standard indicators of the protein content in milk and the yield of milk protein were determined.
— S-
These indicators were: the number of lactations (n), arithmetic means (X), arithmetic mean error ( x ), standard deviation (a). Also, the degree of influence of the investigated factors under their action, both independently and together with other conditioning factors, on the protein content and the yield of milk protein was determined.
The determination of the simultaneous influence of several factors on the effective indicator was carried out using a two-way analysis of variance.
Results and Discussion
To identify bulls by the protein content in milk and the yield of milk protein in daughters, the results of their assessment by these productive traits were analyzed. The average values by the protein content in milk and the yield of milk protein are given for all lactations, regardless of the age of the animals. Table 1 presents the results of the evaluation of the daughters of the bulls most frequently used at the farms.
Bull's nickname and Number identification number lactations
Shturm 4622 Titus 3257 Tekhal' 1726 Surik 8655 Limit 6730 Vud 1703 Bilet 6437 V.V. Jackson 9955 Karlo 1599 Aleut 6619 Colt 69 Ridzhes 1743 Caliber 9707 Ridbul 2771 Sofist 2139 Dar'yus 1029 President 1875 Kavaler 2235 Nickel 7680 Pilmor 1646 Red 1713 Average
118 121 166 133 187 200 169 155 409 112 370 427 125 191 230 172 566 149 246 133 110
of Protein content,%
M ± m ct
3.36 ± 0.015 0.12
3.34 ± 0.015 0.14
3.31 ± 0.013 0.19
3.30 ± 0.014 0.17
3.28 ± 0.012 0.21
3.26 ± 0.011 0.20
3.25 ± 0.012 0.23
3.23 ± 0.013 0.22
3.22 ± 0.008 0.20
3.21 ± 0.015 0.25
3.21 ± 0.008 0.17
3.21 ± 0.008 0.14 3.19 ± 0.014 0.14 3.18 ± 0.012 0.08 3.18 ± 0.011 0.09 3.16 ± 0.012 0.12 3.15 ± 0.007 0.16 3.14 ± 0.013 0.21 3.13 ± 0.010 0.21 3.13 ± 0.014 0.18 3.12 ± 0.015 0.11
3.22 ± 0.012 0.17
Milk protein yield, kg
M ± m ct
180.91 ± 3.78 32.82
183.38 ± 3.75 38.55
201.83 ± 3.18 52.73
176.41 ± 3.52 35.81 138.51 ± 2.97 28.77 203.32 ± 2.87 48.79 132.09 ± 3.12 29.29
140.01 ± 3.26 35.15
173.45 ± 2.01 34.76 124.04 ± 3.84 27.75 142.91 ± 2.11 28.63 185.83 ± 1.97 52.49 180.73 ± 3.63 52.82 165.38 ± 2.94 36.54 176.78 ± 2.68 35.24 167.43 ± 3.09 46.96
186.02 ± 1.73 45.42
154.46 ± 3.32 30.66
165.42 ± 2.59 32.49 159.23 ± 3.52 32.41 188.60 ± 3.92 52.99 167.94 ± 3.04 38.62
Table 1. Parameters of protein content and variability in milk and milk protein yield of daughters of the most commonly used sires.
From the bulls with at least 100 daughters' lactations in the database, the daughters of the bull Shturm 4622 were the best by the studied indicator, and the bull Red 1713 was the worst. The difference between their daughters in terms of protein content in milk was 0.24% and was highly reliable (P>0.999). Improvers in terms of protein content in milk include bulls: Shturm 4622, Titus 3257, Tekhal' 1726, etc. Degrading bulls are the bulls Red 1713, Pilmor 1646, Nickel 7680, etc. Aleut 6619, Ridbul 2771, Caliber 9707 and some others are rated as neutral.
The difference in protein content in milk (Table 2) in the daughters of bulls - improvers is 0.02-0.05% with reliability (P>0.95). In the daughters of neutral bulls - 0.02-0.03% and it is unreliable (P<0.95). Degrading bulls have an insignificant effect on the protein content in daughters' milk.
Nickname, inv. No. bull-fathers
Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Shturm_4622 Titus_3257 Titus_3257 Titus_3257 Titus_3257 Titus_3257 Titus 3257
Tragik_5465
Dar'yus_1029
Karniz_706
O.Robin Et Red_4567
Kesci_38
Security_3597
Pavlin_2085
Rokik Red_9599
Antaeus_7237
President_1875
Reps_20
Kavaler_2235
Shevron_531
Byunas_55
Nickel_7680
Pilmor_1646
Kavaler_2235
Byunas_55
Shevron_531
Nickel_7680
Red_1713
Pilmor 1646
Difference
between
averages,%
0.20 0.20 0.20 0.20 0.20 0.20 0.21 0.21 0.22 0.22 0.22 0.22 0.22 0.23 0.23 0.24 0.20 0.20 0.20 0.21 0.22 0.21
Difference Reliability error, % level
0.022
0.019
0.02
0.02
0.021
0.021
0.019
0.02
0.021
0.016
0.019
0.02
0.018
0.019
0.018
0.02
0.02
0.019
0.018
0.018
0.021
0.02
0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999 0.999
95%-confidence interval
lower border, upper
% border,%
0.16 0.24
0.16 0.24
0.16 0.24
0.16 0.24
0.16 0.25
0.16 0.25
0.17 0.24
0.17 0.25
0.17 0.26
0.18 0.25
0.18 0.25
0.18 0.26
0.19 0.26
0.19 0.26
0.20 0.27
0.19 0.27
0.16 0.24
0.17 0.24
0.17 0.24
0.18 0.25
0.18 0.24
0.17 0.25
Table 2. Evaluation of the reliability of the difference between bulls in terms of protein content in the milk of their daughters.
The milk protein yield per lactation among the daughters of the most widely used bulls also varied. A positive point for breeding opportunities is the fact that the daughters of bulls selected as the best in terms of protein content in milk, also had a fairly high yield of milk protein (from 180 to 201 kg).
At the same time, in the daughters of some bulls (Red 1713, President 1875, etc.) with low protein content, the yield of milk protein was not low (from 164 to 188 kg). That is, those bulls that were degrading in terms of protein content in milk were identified as improving the yield of milk protein due to the relatively high average milk yield of their daughters. The bulls Aleut 6619 and Bilet 6437 were rated the worst in terms of the yield of milk protein in their offspring. With a sufficiently high protein content in the milk of their daughters (3.21% and 3.25%, respectively), the average values of the yield of milk protein turned out to be the smallest-124.0 kg and 132.1 kg, with high reliability (P>0.999).
Scientists Dobryansky et al., (2004) found that a large percentage of the protein in milk and a large total weight for lactation are obtained mainly from the daughters of improving bulls. In their studies, Salute 02530 was named one of such bulls (3.30% and 98.27 kg, respectively). The indicators of the protein content (3.27-3.28%) in the milk of the daughters of the bull Zhoker 275 and Alyur 2453 are slightly lower, and the lowest (3.22-3.23%) in the offspring of the bulls Olivets 3869 and Michman 8182.
It has been determined that the degree of influence of bulls on the protein content in daughters' milk was 7.9%, on the yield of milk protein - 19.6% with high levels of reliability (P>0.999). Regular determination of the protein content in milk makes it possible to establish a rating of breeding bulls by this indicator among their daughters and take this indicator into account during selection. Thus, the value of the sire is one of the main factors that determines the protein content in milk and the yield of milk protein, and one of the most important evaluation criteria.
Some scientists engaged in dairy farming (Dubin, 2002; Palii et al., 2021b; Polkovnikova & Pidpala, 2000) consider it expedient to conduct a selection taking into account complex genetic and environmental factors. A series of analyses of variance was carried out to determine the influence of the "father" factor on the studied productive indicators together with other conditioning factors (Table 3).
Protein content Milk protein yield
Factors degree of influence, % confidence level degree of influence, % confidence level
Father 7.9 >0.999 19.6 >0.999
Calving number-Father 13.3 >0.99 10.0 >0.999
Calving month-Father 7.4 >0.999 6.5 >0.999
Breed combination-Father 6.6 >0.999 5.5 >0.999
Diet concentrate levels-Father 6.1 >0.999 3.7 >0.999
Feeding level-Father 4.9 >0.999 2.6 >0.999
Mother's productivity-Father 4.0 >0.999 4.1 >0.999
Breed-Father 1.8 >0.999 1.9 >0.999
Table 3. Combined influence of the "father" factor with genetic and non-genetic factors.
The degree of father factor co-influence with other factors such as calving number, calving month, breed mix, breed, feeding level, and dietary concentrate levels on protein content and milk protein yield is different.
Among the factors studied, the most strongly influencing pair was "calving number - father". This combination of factors turned out to be one of the most significant and against the background of the final comparative assessment of all investigated combinations. It is essential that the "father" factor, as an independent factor, has a lower influence on the protein content in milk than when interacting with the "calving number" factor. So, the factor "father" causes 7.9% of the protein content in the milk of daughters, and in combination with the factor "calving number" the effect is 5.4% more. At the same time, no such regularity is observed in the yield of milk protein. In this case, the opposite tendency is seen: the "father" as an independent factor has a higher influence in comparison with the variants of its interaction with other studied factors.
To present an illustrative example of the influence of fathers together with other factors on the studied productive traits, gradations characteristic of this influence were singled out, both according to the "father" factor and other factors. Thus, below the productivity of the most characteristic combinations of the joint action of the factors "calving number-father" are presented.
In this case, the analysis of protein content in milk and milk protein yield is shown depending on the lactation number in the context of the bulls used. Significant pairs of gradations have been identified, which show the mechanism and direction of the joint action of this pair of factors (Table 4).
Lactation number Father Number lactations of Average protein content, % Average yield of milk protein, kg
1 V.V. Jackson Еt 9955 46 3.07 128.57
Karlo 1599 149 3.31 182.94
3 V.V. Jackson Еt 9955 29 3.41 151.19
Karlo 1599 44 3.10 174.49
Table 4. Protein and milk protein content in milk of cows depending on calving number and fathers.
It follows from the table that the average protein content and milk protein yield by daughters of bulls differ depending on the number of lactation. Thus, the protein content of the daughters of the bull V.V. Jackson 9955 for the first lactation was significantly lower than for the third. The difference was 0.34%; reliability of the difference P>0.999. And the daughters of the bull Karlo 1599 have the opposite pattern. Consequently, the decisive factor in this case is the combination "bull-lactation number".
Relative to the yield of milk protein, there is a dependence on the combination "father-lactation number". Thus, the daughters of the bull V.V. Jackson 9955 the studied indicator for the third lactation exceeds by 22.6 kg of milk the same indicator for the first lactation, and for Karlo 1599 is the opposite. The significant influence of fathers is also evidenced by studies of domestic and foreign scientists (Bazyshyna, 2017; Dydykina et al., 2021; Khmelnychy, 2019; Lyubynsky & Kasprov, 2020; Savegnago et al., 2013; Shulyar, 2018; Vechorka & Mazur et al., 2018; Yovenko, 2002). They argue that the best offspring are born from the best fathers more often than from the worst ones. The greater or lesser part of the phenotypic diversity of offspring is caused by genotypic diversity, which comes from the fathers through the genetic information that is embedded in the gene complexes. The rather high influence of the genetic factor "father" and its combinations with others indicates the advisability of further studies aimed at specifying the effects of these influences.
Conclusion
It has been found that the degree of influence of the "father" factor on the protein content in milk of cows is 7.9%, on the yield of milk protein-19.6% with a high degree of reliability (P>0.999). Among the factors in the formation of which the component "father" is involved, the most strongly influencing is "calving number - father", the degree of influence of which is: by protein content 13.3%; by the yield of milk protein 10.0%, respectively, with a high degree of reliability (P>0.999).
References
Bazyshyna, I.V. (2017). Formation of economically useful traits of dairy cattle depending on the father's origin, line and related group. Breeding and genetics of animals, 53:69-78.
Danshin, V.A. (2008). Assessment of the genetic value of animals. Kiev: Agrar. The science.
Dobryansky, V., Talko, G., Ivanova, V. (2004). Protein milk is a problem of national importance. Offer, 10:90-91.
Dubin, A.M. (2002). On the question of the efficiency of selection of bulls. Bulletin of Agricultural Science, 5:51-53.
Dydykina, A.I., Prudnikov, V.H., Kolisnyk, O.I., Vasylieva, Y.O., Palii, A.P., Paliy, A.P., Petrov, A.M. (2021). Influence of keeping
technology on the weight gain of the Aberdeen-Angus breed young animals in the colostrum period. Ukrainian Journal of Ecology,
11:27-32.
Kochuk-Yashchenko, O.A., Kucher, D.M. (2020). Application of the concept of the desired type in the herd of Jersey breed. Interdepartmental thematic scientific collection: Breeding and genetics of animals, 59:41-50.
Korshun, S.I., Klimov, N.N. (2016). The main genetic statistical parameters of indicators of productive dairy cattle. Tavrichesky scientific observer, 5:33-37.
Krasota, V.F., Japaridze, T.G., Kostomakhin, N.M. (2006). Breeding of farm animals. Ear.
Krugliak, A.P., Krugliak, T.O. (2020). Variability and heredity of the bull's breeding value of different genealogical formations of the Holstein breed. Interdepartmental Thematic Scientific Collection: Breeding and Genetics of Animals, 59:51-59. Kuznetsov, V.M. (2002). Improvement of the system of breeding assessment of animals. Bulletin of the Russian Agricultural Academy, 3:13-16.
Lazarenko, V., Ermilov, A., Antipova, N. (2004). Selection, evaluation and use of sire bulls in the Moscow region. Dairy and Beef Cattle Breeding, 3:18-20.
Lyubynsky, O.I., Kasprov, R.V. (2020). Productive qualities of cows of different selection groups of Bukovynian factory type of Ukrainian red-spotted dairy breed. Breeding and Genetics of Animals, 59:60-66.
Mazur, N.P., Fedorovich, E.I., Fedorovich, V.V. (2018). Economic useful features of dairy cows and their connection with productive longevity. Breeding and Genetics of Animals, 56:50-64.
Osipenko, T.L., Admina, N.G., Palii, A.P., Chechui, H.F., Mihalchenko, S.A. (2018). Influence of the level feeding high-productive cows on obtaining biosafety products. Ukrainian Journal of Ecology, 8:189-194.
Palii, A.P., Admina, N.G., Mihalchenko, S.A., Lukyanov, I.M., Denicenko, S.A., Gurskyi, P.V., Pal iy, A.P., Kovalchuk, Y.O., Kovalchuk, V.A., Kuznietsov, O.L., Gembaruk, A.S., Solodchuk, A.V. (2020). Evaluation of slaughter cattle grades and standards of cull cows. Ukrainian Journal of Ecology, 10:162-167.
Palii, A.P., Handola, Yu.M., Shevchenko, I.O., Stotskyi, A.O., Stotskyi, O.G., Sereda, A.I., Levkin, D.A., Ulko, L.G., Shkromada, O.I., Paliy, A.P. (2020b). Assessment of cow lactation and milk parameters when applying various milking equipment. Ukrainian Journal of Ecology, 10:195-201.
Palii, A.P., Osipenko, T.L., Patryeva, L.S., Chechui, H.F., Kirovych, N.O., Kosenko, S.Y., Nikolenko, I.V., Kalabska, V.S., Boyko, Y.A., Paliy, A.P. (2021a). Dependences between the milk protein characteristics in cattle and offspring. Ukrainian Journal of Ecology, 11:313-319.
Palii, A.P., Osipenko, T.L., Syromiatnikov, P.S., Boyko, Y.A., Nechyporenko, V.V., Levchenko, I.V., Ostapenko, V.I., Prykhodko, M.F., Korzh, O.V., Popsuy, V V., Paliy, A.P. (2021). Influence of cattle breed combinations on milk production: results of the Analysis of Variance. Ukrainian Journal of Ecology, 11:25-31.
Paliy, A.P. (2016). Innovative foundations for the production of high-quality milk. Monograph. Kharkiv: Mis'kdruk.
Polkovnikova, O., Pidpala, T. (2000). Evaluation of the genotype of breeding bulls by combined traits in their daughters. Livestock of
Ukraine, 3:15-16.
Polupan, Yu.P., Gavrilenko, M.S. (2008). Methods of assessment of selection-genetic situation in breeding herds. Agricultural Science Production, 4:19.
Prudov, A.I., Dunin, I.M. (2005). The use of the Holstein breed for intensifying the selection of dairy cattle. Moscow: Niva Rossii. Savegnago, R.P., Rosa, G.J.M., Valente, B.D., Herrera, L.G.G., Carneiro, R.L.R., Sesana, R.C., El Faro, L., Munari, D.P. (2013). Estimates of genetic parameters and eigenvector indices for milk production of Holstein cows. Journal of Dairy Science, 96:72847293.
Selionova, N.I., Kovaleva, G.P. (2015). Comparative assessment of bulls-producers of the main dairy breeds on the productivity of daughters. Animal Science, 1:8-10.
Shulyar, A.L. (2018). Genetic determination of economically useful traits of cows of the Ukrainian black-spotted dairy breed.
Scientific Bulletin of Lviv National University of Veterinary Medicine and Biotechnology S. Z. Gzhytsky, 89:35-41.
Shulyar, A.L., Shulyar, A.L., Omelkovich, S.P., Tkachuk, V.P., Andriychuk, V.F. (2020). Genetic conditionality of economically useful
traits of Ukrainian black-spotted dairy cows. Interdepartmental thematic scientific collection: Breeding and Genetics of Animals,
60:92-98.
Titova, S.V. (2016). Duration of productive use and lifelong productivity of Holsteinized black-and-white cattle. Agricultural Science of the Euro-North-East, 2:68-72.
Titova, S.V. (2017). The indicator of the safety of daughters in the assessment of bulls. Mari State University Bulletin, 3:48-52. Vechorka, V.V., Khmelnychy, L.M. (2019). Genetic factors influencing the productivity of cows of the Ukrainian black-spotted dairy breed. Breeding and Genetics of Animals, 57:22-28.
Yovenko, I.Y. (2002). On the genetic improvement of the Ukrainian black-spotted dairy breed. Bulletin of Agricultural Science, 1:8082.
Zubets, V.V., Burkat, V.P., Melnik, Yu.F. (1997). Genotype assessment, selection and use of breeding bulls. Genetics, Selection and Biotechnology in Animal Husbandry, pp:439-489.
Citation:
Palii, A.P., Osipenko, T.L., Chigiryov, V.A., Gurko, I.Y., Petrov, R.V., Berezovsky, A.V., Khitska, O.A., Furman, S.V., Lisoh urska, D.V., Lisohurska, O.V. (2021). Influence of the fixed "father" factor on the protein content in milk and the yield of milk protein in cattle. Ukrainian Journal of Ecology, 11 (3), 353-359.
I («0Е^^^И! This ууогк ¡s licensed under a Creative Commons Attribution 4.0. License
