Estimating Breeding Values for Milk Production and Mastitis Traits for Holstein Cattle in Egypt

Faid-Allah E. 2018. Estimating breeding values for milk production and mastitis traits for Holstein cattle in Egypt. JITV 23(4): 159-167. DOI: http://dx.doi.org/10.14334/jitv.v23i4.1845 This study was carried out to evaluate the sires and dams genetically for milk production and mastitis traits in Egyptian 12 herds of Holstein cattle using Best Linear Unbiased Prediction via MTDFREML program. The data was obtained from a commercial farm called Dena, located in Cairo-Alex Desert Road (80 Km), Menofia, Egypt. Data included 4791 cows, 4227 dams and 248 sires that represented the period from 2007 to 2014. Estimating breeding values for milk production traits as cumulative milk yield at 90 days (90-DM), cumulative milk yield at 180 days (180-DM), cumulative milk yield at 270 days (270-DM), cumulative milk yield at 305 days (305-DM), and number of mastitis infection around the season of lactation (MAST). The averages of the 90-DM, 180-DM, 270-DM, 305-DM and MAST were 3026.3±655.1 kg, 5873.3±1081.1 kg, 7891.1±2692.2 kg, 9611.2±1897.9 kg, and 0.712±1.2 time/parity, respectively. Estimates of heritability for the previous traits were 0.11±0.016, 0.15±0.014, 0.18±0.012, 0.22±0.015, and 0.09±0.029, respectively; genetic variance were 47206.2 kg, 175300.6 kg, 1304654.4 kg, 792411.6 kg and 0.12 time/parity, respectively; and phenotypic variance were 429147.6 kg, 1168670.6 kg, 7248079.9 kg, 3601870.9 kg, and 1.35 time/parity, respectively. The EBV values as average, SD, (Min: Max) for sires were 0.0±0.179 (-0.4: 0.66) for MAST, 0.0±86.176 (-263.1: 245.4) for 90-DM, 0.0±227.523 (-600.3: 800.3) for 180-DM, 0.0±413.48 (-323.3: 1277.7) for 270-DM and 0.0±440.26 (-1280.9: 1565.1) for 305-DM. Also, The EBVs for dams were 0.0±0.055 (-0.14: 0.45) for MAST, 0.033±26.24 (-142.8: 103.0) for 90-DM, 0.074±76.81 (-360.2: 289.6) for 180-DM, 0.045±139.66 (-591.9: 529.2) for 270-DM and 0.266±154.1 (-666.3: 617.6) for 305-DM. These results provide that the selection of sires and dams will improve the traits of milk production and mastitis in this herd because of the wide differences in genetic potential among sires and dams.


INTRODUCTION
Egypt imports semen of foreign bulls via many companies around the world under the supervision of the Agricultural Ministry, Egypt.But, the final decisions were taken via farm managers in the order of selected bulls to inseminate the cow populations almost without real breeding consultancy.There is no real scientific genetic evaluation and follow up for these bulls and its effects of the genetic pool in cow populations in Egypt.There are many different trials of sire breeding value estimated by different researchers, under Egyptian conditions but almost not for application in the field.The estimating of BV's for sires for different economic traits (i.e., Milk production, milk quality, health, reproduction, durability, milking speed) is the main goal to successful breeding programs for cattle genetic improvement.One of the main criteria for enhancing the genetic potential of progenies in a herd is to use proven sires to transmit superior genetic potential for economic traits (Banik & Gandhi 2010).The sire evaluation based on milk yield was the most widely used criteria; milk yield is an important economic trait in livestock species.It represents a major source of income in most dairy enterprises (Al-Samarai et al. 2015).At the past decade, most dairy cattle breeding goals consist of functional traits and milk production traits (Miglior et al. 2005).In addition, functional traits are a collective term for all traits that increase efficiency by lowering the costs of production (Groen et al. 1997).Economic traits are generally controlled by genetic factors but environmental influences like, year of calving, the season of calving; parity and age at first calving have significant effects on milk yield (Pirzada 2011).Identification of the best sires with higher accuracy is of enormous importance for any breed improvement program, as sires are easily and rapidly spread in many herds used progeny test (Kumar & Chakravarty 2014).In the recent past, the best linear unbiased prediction (BLUP) procedure has been widely used as a standard method of sire evaluation.
The objective of this study was to estimate breeding values (EBVs) for Holstein sires and dams of milk production traits (90-DM, 180-DM, 270-DM, 305-DM), and MAST in 12 herds under Egyptian condition.

Data and economic traits
Data were obtained from a commercial farm called Dena, located in Cairo-Alex desert road (80 Km), Menofia, Egypt.Data included 4791 cows as progenies of 4227 dams and 248 sires that represented the period from 2007 to 2014.
Studied traits were milk production traits as cumulative milk yield at 90 days (90-DM), cumulative milk yield at 180 days (180-DM), cumulative milk yield at 270 days (270-DM), cumulative milk yield at 305 days (305-DM) milk yield and hygiene trait as number of mastitis infection around the season of lactation (MAST) Animals were housed free in shaded open yards, grouped based to milk yield, and fed on TMR system around year based to NRC (NRC 2001).Holstein heifers were AI using semen of Holstein proven sires, around 350 kg of weight and pregnancy was detected at day sixty after service.The animals were machinery milked in milking parlour 3 times/day.
The other researchers reported that heritability estimates ranged from 0.27 to 0.36 by method of REML in Holstein cattle (Tuna 2004;Atashi et al. 2006;Guler et al. 2010), and heritability estimates of milk yield for Brown Swiss in Turkey for first and all lactations were 0.23 and 0.19, respectively (Muammer et al. 2009).The present result was slightly lower than previously showed results for 305-DM and milk in the first three parities (0.51, 0.49, and 0.47) using the model of RR model for Holstein cattle in Netherland (De Roos et al. 2004).In spite of, it was still higher than 0.02 and 0.10 as heritability estimates of 305-DM and test day milk yields for Brown Swiss cattle in the USA, respectively (Suleyman & Ali 2008).The high estimate of heritability for total milk yield in Holstein cow in Yemen was 0.35±0.12(Al-Samarai et al. 2015).However, the low estimate of heritability for 305 days milk yield from the first three lactation records was 0.15±0.04 in Ethiopian Holstein cattle (Ayalew et al. 2017).
Differences in heritability estimates are caused by the correction for non-genetic factors, the records number used in estimation, the genetic constitution of the breed, research objects, management, climate and different model affecting genetic and environmental variances, and the estimation method (Abou-Bakr et al. 2006;Fu et al. 2017).
Table 2 and Figure 1 shows that the EBVs for sires had a wide range of all studied traits may be due to export sire from many sources around the world for Holstein cattle and change the desired goal of breeders from milk production traits as the main goal to functional and hygiene traits.In addition, The EBVs for dam had a smaller range than sires of all studied traits may be due to the selection of the superior cows inside the farms.Since 2012 the breeders were being used proven sires for mastitis and functional traits with lower breeding values for milk production traits, further improvement of mastitis performance and it explained the high genetic variation for sires EBVs.
In Egypt, EBVs estimated via Best Linear Unbiased Prediction (BLUP) method for 305-DM were in between -466 and 681 kg estimated from 1653 records of daughters/163 sires (Abdel-Glil 1991), and in between-506 and 675 kg estimated from 1931 lactation records of daughters/76 sires (Atil & Khattab 1999).EBVs of all animals from 3464 records of Holstein cows/99 sires ranged from -4917.4 to 4731.3, -3863.1 to 3076.4,for total milk yield, 305-DM, respectively (Radwan et al. 2015).Predicted transmitting abilities for mastitis trait ranged from −0.0785 to 0.0965 for a number of cases of clinical mastitis, the ranges were from −0.2184 to 0.3884 (Perez-Cabal et al. 2009).EBVS for milk yield at first lactation using BLUP method ranged from 1262.90 to 1543.65 kg for Sahiwal sires (Duelkar & Kothekar 1999), as averageEBVs in Friesian cattle in Egypt as average (Min:Max) for 305-DM was 65.01 kg (-300.7:706), total milk yield was 98.27 kg (-371.5:1105.7),cumulative milk yield in 90 days was 13.96 kg (-181:298), cumulative milk yield in 150 days was 15.73 kg (-362:381) and cumulative milk yield in 180 days was 49.70 kg (-397:390) (Zein 2014).EBVs for total milk yield , 305-DM from 3464 records of Holstein cows in Egypt ranged -2096 to 2117, -372.9 to 315.9 kg, respectively, the values for dams were ranged from -1372 to 2113, -396.2 to 226.8 kg, respectively.EBVs for sires were ranged from -1095 to 1186, -245.9 to 171.9 kg for the previous traits, respectively (El-Bayoumi et al. 2015).EBVs of sires for the total milk yield (the average number of daughter/sire was 3.51) in between -471.88 and 443.8 with a marginal difference of 915.68 kg between lower and higher value in Holstein cattle in Yemen (Al-Samarai et al. 2015).EBVs for milk production in Holstein cattle in Egypt as a total milk yield ranged from -2736.6 to 3284.5, and for 305-DM ranged from -1698.0 to 1337.8 of cows, the EBVs for sires were ranged between -1056.8 to 659.1, and -737.1 to 621.9, respectively.EBVs for dams were ranged from -2835 to 2979.1, -985.2 to 1875.1 for the previous traits estimated from 1807 lactation records of daughters/73 sires, respectively (Salem & Hammoud 2016).
Table (3) shows that the values of EBV via MTDFREML program in percentiles of studied traits with great variation for 248 Holstein sires that imported for 12 herds in Egypt as semen for artificial insemination.High genetic variation was reported among the EBVs of sires as reported by many researchers in cattle (Dalal et al. 1999;Dubey et al. 2006;Banik & Gandhi 2006;Kumar et al. 2008;Moges et al. 2009).
Table (3) shows that the sires' EBVs ranged from -263.09 to 245.43 kg for milk yield at 90 days, -600.32 to 800.34 for milk yield at 180 days, -1323.29 to1277.72 for milk yield at 270 days, and -1280.9 to 1565.05 for milk yield at 305 days.Also, the sires' EBVs ranged from -0.4 to 0.66 for sire for the MAST.
Milk yield EBVs ranged in -1013.9 to 1965.7 kg, The average of sires EBV via DFREML for milk yield at 1 st parity was 3050.84 kg out of 57 sires 30 (52.63%) sires had EBV above the average and 24 (47.32%)sires had the below the average (Zutere 2008).
Table (4) shows that the dams' EBVs ranged from -142.76 to 103.02 for milk yield at 90 days, -360.21 to 289.55 for milk yield at 180 days, -591.91 to 529.21 for milk yield at 270 days, and -666.31 to 617.57 for milk yield at 305 days.Also, the dams' EBVs ranged from -0.14 to 0.45 for the dam for MAST About 50% out of 4227 dams showed higher values than the average for milk production traits, 3170 dams (75%) out of 4227 dams as a best 75% showed higher EBVs than -16.0655, -44.1182, -70.4308 and -99.0659 kg for 90-DM, 180-DM, 270-DM, and 305-DM, respectively.About 50% out of 4227 dams showed lower values than the average for the MAST.Also, 3170 dams (75%) out of 4227 dams showed lower EBVs than-.0354forMAST.
The EBVS of milk yield at first lactation of Sahiwal sires using BLUP method ranged from 1153.95 to 2560.29 kg respectively.38 out of 112 sires (33.93%) had EBVS above the average, while 74 sires (66.07%) had EBVS below the average.The top ranking sires had 35.46% genetic superiority over the overall average, whereas below average ranking sires had 38.95% low EBVS than the overall average (Singh & Singh 2016).

Figure 1 .
Figure 1.Box and Whisker plot of EBVs for milk production and mastitis traits in Holstein cattle.

Table 1 .
Descriptive statistics and genetic parameters of milk production traits and mastitis in Holstein cattle

Table 2 .
Estimated breeding values for milk production and mastitis traits in Holstein cattle

Table 4 .
EBVs Percentiles for studied Holstein cows (as a dam)