Assessment of Inbreeding Depression and Inbreeding Trend of Production Traits in Iraqi Holstein Cows

Main Article Content

Farzad Moradpour
Hana Hamidi


Inbreeding is defined as the probability that two alleles at any locus are identical by descent and occur when related individuals are mated to each other. A total of 123427, 115810 and 88361 records of 412-d yields of milk, fat and protein of Iraqi Holstein cows were collected from 1995 to 2010 in 838 herds used to estimation the inbreeding depression and inbreeding trend. Pedigree records of Iraqi Holstein cow were used to assessment inbreeding coefficients and these coefficients ranged from 0 to 42%. Animal model was used to estimation inbreeding depression on traits. Fixed effects included in statistical model were herd – year, age at calving and inbreeding coefficient as continuous and discrete variable. When considering inbreeding as continuous variable in model, the inbreeding depression for 412-d yields of milk, fat and protein were -28.19, -0.98 and -0.88 kg per 1% increase in inbreeding in Iraqi Holsteins, respectively. In this group of animal that inbreeding coefficient was between 0 < F ≤ 5.34 inbreeding was not caused reduction in production traits. However, in group of animal that inbreeding coefficient was greater than 5.34, and inbreeding depression in production traits was observed. The result of this study confirms of inbreeding depression in Iraqi Holstein cows.

Fat yield, inbreeding trend, inbreeding depression, Iraqi holstein cows, protein yield.

Article Details

How to Cite
Moradpour, F., & Hamidi, H. (2019). Assessment of Inbreeding Depression and Inbreeding Trend of Production Traits in Iraqi Holstein Cows. Asian Journal of Biotechnology and Bioresource Technology, 5(4), 1-9.
Original Research Article


Falconer DS, Mackay TFC. Introduction to quantitative genetics. Fourth edition. Addison Wesley Longman, Harlow, Essex, UK. 1996;464.

Fernandez J, Toro MA. The use of Mathematical programming to control inbreeding in selection schemes. Journal of Animal Breeding Genetic. 1999;116: 447-466

Karoui S, Díaz C, Serrano M, Cue R, Celorrio I, Carabano MJ. Time trends, environmental factors and genetic basis of semen traits collected in Holstein bulls under commercial conditions. Animal Reproduction Science. 2011;124: 28–38.

Thompson JR, Everett RW, Hammerschmidt NL. Effects of inbreeding on production and survival in Holsteins. Journal of Dairy Science. 2000;83:1856-1864.

Tohidi R, Vaez Torshizi R, Moradi Shahrbabak M, Sayyad Nejad MB. Inbreeding and its effects on milk and fat yields ofIran Holsteins. Proc. 7th World Congr. Genet. Appl. Livest. Prod., CD-ROM Commun. 2002;21:01–55.

Parland MC, Kearney JF, Rath M, Berry DP. Inbreeding effects on milk production, calving performance, fertility and conformation in Irish Holstein Friesians. Journal of Dairy Science. 2007;90:4411–4419.

Croquet C, Mayeres P, Gillon A, Vanderick S, Gengler N. Inbreeding depression for global and partial economic indexes, production, type, and functional traits. Journal of Dairy Science. 2006;89:2257-2267.

Falconer DS, Mackay TFC. Introduction to quantitative genetics. 4th Ed. Longman, Essex, UK; 1996.

Hennas SA, Young CW, Rust JW. Effects of mild inbreeding on productive and reproductive performance of Guernsey cattle. Journal of Dairy Science. 1987;70: 712-719.

Hodges J, Tannen L, McGillivray BJ, Hiley PG, Ellis S. Inbreeding levels and their effect on milk, fat and calving interval in Holstein-Friesian cows. Can. Journal of Animal Science. 1987;59:153-159.

Hudson GFS, Van Vleck LD. Effects of inbreeding on milk and fat production, stayability and calving interval of registered Ayrshire cattle in the Northeastern United States Journal of Dairy Science. 1984; 67:171-179.

Kunaka K, Makuza M. Environmental factors affecting milk production in the holstein-friesian population of Zimbabwe. Pakistan Journal of Biological Sciences. 2005;8(7):989-994.

Falconer DS. Introduction to quantitative genetics. John Willey and Sons, Inc. New York, NY. 3rd ed. Loogman, Burnt Mill. Harlow, Essex. Eogl; 1989.

Smith LA, Cassell BG, Pearson RE. The effects of inbreeding on the lifetime performance of dairy cattle. Journal of Dairy Science. 1998;45:2729-2737.

Fuerst-Waltl B, Schwarzenbacher H, Perner C, Sölkner J. Effects of age and environmental factors on semen production and semen quality of Austrian Simmental bulls. Animal Reproduction Science. 2006;95:27–37.

Ponzoni RW, Newman S. Dvelopment of breeding objectives for Australian

beef cattle production. Animal Reproduction Science. 1989;49:35-47.

Weller J, Ezra E. Genetic analysis of Israel. Holstein dairy cattle population for production and nonproduction traits with a multitrait animal model. J. Dairy Sci. 2005;87:1519-1527.

Sewalem A, Kistemaker GJ, Miglior F. Relationship female fertility and production traits in Canadian Holsteins . Journal of Dairy Science. 2010;93:4427-4434.

Henderson CR. A simple method for computing the inverse of a numerator relationship matrix used in prediction of the Asturcon pony as an example. Genetics Selection Evolution. 1976;30:397-405.

Sargolzaei M, Iwaisaki H, Colleau JJ. CFC: A tool for monitoring genetic diversity. In: Proceedings of 8th World Congress on genetic applied to livestock production. Belo Horizonte, Minas Gerais. Brazil. 2006; 27-28.

Gilmour AR, Gogel BJ, Cullis BR, Welham SJ, Hompson R. ASREML user guide release 1.0. VSN International Ltd., Hemel Hempstead, U.K; 2002.

Miglior F. Centre for genetic improvement of Uvestock. Department of animal and poultry Science University of Guelph, ON, Canada N1G 2W1. Journal of Dairy Science. 1992;54:76-82.

Schacffer LR. Application of random regression models in animal breeding.

Journal Livestock Production Science. 2004;86:35-45.

Rokouei M, Vaez Torshizi R, Moradi Shahrbabak M, Sargolzaei M, Sorensens AC. Monitoring inbreeding trends and inbreeding depression for economically important traits of Holstein cattle in Iran. Journal of Dairy Science. 2010;93:3294–3302.

Hamami H, Rekik B, Bastin C, Soyeurt H, Bormnn J, Stoll J, Gengler N. Environmental sensitivity for milk yield in Luxembourg and Tunisian Holsteins by herd management level. Journal of Dairy Science. 2009;92:4604-4612.

Maiwashe A, Nephawe KA, Theron HE. Estimates of genetic parameters and effect of inbreeding on milk yield and composition in South African Jersey cows. South African Journal of Animal Science. 2008;38(2):119-125.

Nyamushamba GB. Comparative evaluation of non-genetic factors affecting milk yield and composition of Red Dane and Jersey cattle in Zimbabwe.

Khanzadeh H, Gavi Hossin Zadeh N, Naserani M. Estimation of genetic Parameters and trends for milk fat and protein percentages in Iranian Holsteins using random regression test day model. Archives Animal Breeding. 2012; 56:1-21.

Mandal A, Pant KP, Rout PK, Roy R. Effects of inbreeding on lamb survival in aflock of Muzaffarnagari sheep. Asian-Australasian Journal of Animal Sciences. 2004;17(5):594-597.

Hamidi NM. Effects of environmental factors on milk yield, lactation length and dry period in Tunisian Holstein Cows; 2012.

Sewalem A, Kistemaker GJ, Miglor F, Vandoormal BJ. Analysis of inbreeding and its relationship with functional longevity in Canadian dairy cattle. Journal of Dairy Science. 2006;89:2210-2216.

Hudson GFS, VanVleck LD. Inbreeding of artificially bred daily cattle in the northeastern United States. Journal of Dairy Science. 1984;67:161-168.

Szyda J, liu Z, Reinhardt F, Reents R. Estimation of quantitative trait loci

parameters for milk production traits in German Holstein dairy cattle population. Journal of Dairy Science. 2005;88(1):356-367.

Thompson R. Design of experiments to estimate genetic parameters within population. In: Evolution and Animal Breeding WG. Hill and TFC Mackay. CAB International. 1996;65:169-174.

Jamrozik J, Schaeffer LR. Estimates of genetic parameters for a test- day model with random regressions for yield traits of first lactation Holsteins. Journal of Dairy Science. 2007;90:1564-1574.

Ravagnolo O, Misztal I. Gentic component of heat stress in dairy cattle, parameter estimation. Journal of Dairy Science. 2000;83:2126-2130.