SELECTION FOR PROLIFICACY IN ROMNEY SHEEP I. DIRECT RESPONSE TO SELECTION

Bhuiyan, A.K.F.H.,Curran, M.K. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.1

A selection experiment with Romney Marsh sheep was used to evaluate direct responses to selection. Two flocks were maintained; a) the selection line formed in 1979 by the Romney Group Breeders to select for high prolificacy, defined as the number of live lambs born per ewe joined per year and b) a control line, established in 1982, where flock replacements were chosen at random. Predicted responses per year of birth female group and per year respectively were 0.033 and 0.027 live lambs. The rate of predicted response per year was within the theoretical expected range from 0.01 to 0.03 of the mean. The rates of realized response in prolificacy per year of birth female group and per year respectively were 0.026 and 0.021. These estimates of realized responses represented between 0.01 and 0.02 of the control line mean per year.

Mitochondrial DNA Diversity and Origin of Red Chittagong Cattle

Bhuiyan, M.S.A.,Bhuiyan, A.K.F.H.,Yoon, D.H.,Jeon, J.T.,Park, C.S.,Lee, J.H. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.10

To determine the origin and genetic diversity of Red Chittagong (RC) cattle in Bangladesh, we analyzed mitochondrial DNA displacement loop (D-loop) sequences of 48 samples along with 22 previously published sequences from Bos indicus and Bos taurus breeds. Twenty five haplotypes were identified in RC cattle that were defined by 44 polymorphic sites and nucleotide diversity was $0.0055{\pm}0.0026$. The estimated sequence divergence times between RC and other zebu cattle breeds studied ranged between 22,700-26,900 years before present (YBP) which, it is suggested, predate domestication of RC cattle. Furthermore, it is assumed that introgressions have occurred in this breed mainly from Indian zebu breeds in the recent millennia. The phylogenetic studies showed RC cattle clustered with Bos indicus lineage with two distinct haplogroups representing high genetic variability of this breed. These findings can be used for designing proper breeding and conservation strategies for RC cattle in Bangladesh.

The Genetic Development of Sire, Dam and Progenies and Genotype ${\times}$ Environment Interaction in a Beef Breeding System

Bhuiyan, A.K.F.H.,Dietl, G.,Klautschek, G. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.1

The aim of this study was to investigate genetic development and genotype${\times}$environment interactions (GEI) in postweaning body weight of fattening bulls at the end of test period (WT-T) under various beef fattening environments. Data on a total of 24,247 fattening bulls obtained from the industrial farm, breeding farms and testing stations were used. Heritability estimates for WT-T in all environments were nearly similar. Significant genetic developments of sire, dam and progenies for WT-T were observed in all environments. However, many differences in annual genetic developments between the environments were significant. The genetic correlations for WT-T between industrial farm and breeding farms, industrial farm and testing stations and breeding farms and testing stations were respectively 0.004, 0.004 and 0.013. These low estimates of genetic correlations and significant differences in genetic developments among environments clearly show the existence of GEI for WT-T among various fattening environments. Results of this study indicate the need for environment-specific genetic evaluation and selection of beef bulls for commercial beef production.

Statistical Genetic Studies on Cattle Breeding for Dairy Productivity in Bangladesh: I. Genetic Improvement for Milk Performance of Local Cattle Populations

Hossain, K.B.,Takayanagi, S.,Miyake, T.,Moriya, K.,Bhuiyan, A.K.F.H.,Sasaki, Y. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.5

Genetic parameters for dairy performance traits were estimated, breeding values for the traits of all breeding sires and cows were predicted and the genetic trends were estimated using the breeding values in the Central Cattle Breeding Station (CCBS). A total of 3,801 records for Bangladeshi Local, 756 records for Red Sindhi and 959 records for Sahiwal covering the period from 1961 to 1997 were used in this analysis. Traits considered were total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). The genetic parameters were estimated by the REML using MTDFREML program. The breeding values were predicted by a best linear unbiased prediction (BLUP). In all sets of data, the genetic trends for the dairy performance traits were computed as averages of breeding values for cows born in the particular year. The estimates of heritability for TLP (0.26 and 0.27) and DMY (0.28 and 0.27) were moderate in Bangladeshi local and Red Sindhi breed, respectively. Furthermore, the heritability estimate for LL (0.24) was moderate in Red Sindhi. The estimates of heritabilities for all traits were low in Sahiwal. The repeatability estimate was high for TLP, moderate for LL and moderate to high for DMY. All variances estimated in Bangladeshi Local were low, comparing the respective values estimated in both Red Sindhi and Sahiwal. On the other hand, additive genetic variances for the three traits were estimated very low in Sahiwal. The genetic trends for the three dairy production traits have not been positive except for the recent trend in Bangladeshi Local.

SELECTION FOR PROLIFICACY IN ROMNEY SHEEP II. CORRELATED RESPONSES

Bhuiyan, A.K.F.H.,Curran, M.K. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.1

A selection experiment with Romney Marsh sheep was used to evaluate correlated responses to selection. The selected flock was formed in 1979 by the Romney Group Breeders where selection was for prolificacy, defined as the number of live lambs born per ewe joined per year and a randomly selected control flock was established in 1982. Selection for prolificacy resulted in (i) increased ewe fertility, (ii) increased ewe ovulation rate, (iii) increased ewe litter size, (iv) decreased ewe body weight, (v) decreased lamb birth weight and (vi) decreased lamb 8-week weight. The rates of correlated responses per year respectively for ewe fertility, ewe ovulation rate, ewe litter size, ewe body weight, lamb birth weight and lamb 8-week weight were 0.033(0.002), 0.043(0.016), 0.019(0.005), -0.017(0.066), -0.055(0.025) and -0.150(0.057).

ADDITIVE AND HETEROSIS EFFECTS ON MILK YIELD AND BIRTH WEIGHT FROM CROSSBREEDING EXPERIMENTS BETWEEN HOLSTEIN AND THE LOCAL BREED IN BANGLADESH

Hirooka, H.,Bhuiyan, A.K.F.H. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.3

Data from purebred and crossbred cattle involving Holstein and the Local breed in Bangladesh were used to estimate the genetic effects on average daily milk yield and birth weight A total of 877 records on average daily milk yield for 4 types of breed groups and a total of 418 records on birth weight for 5 breed groups were analyzed. Two different methods were applied in this study; the least squares analysis of variance approach and the linear regression approach. Breed group effects were highly significant for both average daily milk yield and birth weight. The result showed that straightbred Holstein produced the highest milk yield and the 7/8 crosses ranked highest in birth weight For the two traits, the additive breed effect was highly significant, whereas the individual heterosis effect was not significant. Furthermore, this study showed a negative maternal heterosis for average daily milk yields and a positive maternal heterosis for birth weight Comparing the breed least squares means obtained from the linear regression approach revealed that straightbred Holstein produced the highest average milk yield and the 3/4 crosses were predicted to have the largest birth weight. It is indicated that the linear regression approach can adequately separate the genetic component of performance, estimate unknown crossbreeding parameters and predict unknown performance of crosses which are not include in the original data.

Statistical Genetic Studies on Cattle Breeding for Dairy Productivity in Bangladesh: II. Estimation of Reciprocal and Heterosis Effects and Optimum Crossbreeding System between the Local Breeds and Exotic Breeds for Milk Performance

Hossain, K.B.,Takayanagi, S.,Miyake, T.,Bhuiyan, A.K.F.H.,Sasaki, Y. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.6

Reciprocal effects among local breeds and additive and heterosis effects were estimated for total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). Procedures for an optimum crossbreeding system were examined by comparing various crossbred combinations. Three data sets were chosen from the total records collected from 1962 to 1997. Data set I with a total of 5,938 records composed of 9 breed groups for reciprocal crosses, data set II with a total of 6,064 records composed of 5 breed groups for additive and heterosis effects and data set III with a total of 10,319 records composed of 42 breed groups for optimum crossbreeding system were analyzed. The least squares ANOVA was used. The reciprocal crosses between Red Sindhi and the Bangladeshi Local showed significant difference. When the Red Sindhi was used as cow, the cross was superior to the opposite in terms of the three performance traits. The results showed that additive breed effects on both TLP and DMY were positive and highly significant between Bos indicus and Bos taurus, whereas the individual heterosis effects were not significant. In general, any local breeds were improved two to three times by crossing with the Friesian once or twice. However, the effect was reduced when the grading up with the Friesian was repeated more than twice. On the other hand, when the local breed was crossed with the other breeds such as Holstein and Jersey, the improvement of TLP was less. Crossing the F1 cows with the Friesian bull gave further improvement. Almost the same trends were found also for LL and DMY. The local breeds and their crosses are raised mainly for draft animals, then it is recommended that the crossbreds between the local cows and Friesian are used for dairy purposes and more than 75% Friesian blood is used for beef.

Genome-wide Single Nucleotide Polymorphism Analyses Reveal Genetic Diversity and Structure of Wild and Domestic Cattle in Bangladesh

Uzzaman, Md. Rasel,Edea, Zewdu,Bhuiyan, Md. Shamsul Alam,Walker, Jeremy,Bhuiyan, A.K.F.H.,Kim, Kwan-Suk Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.10

In spite of variation in coat color, size, and production traits among indigenous Bangladeshi cattle populations, genetic differences among most of the populations have not been investigated or exploited. In this study, we used a high-density bovine single nucleotide polymorphism (SNP) 80K Bead Chip derived from Bos indicus breeds to assess genetic diversity and population structure of 2 Bangladeshi zebu cattle populations (red Chittagong, n = 28 and non-descript deshi, n = 28) and a semi-domesticated population (gayal, n = 17). Overall, 95% and 58% of the total SNPs (69,804) showed polymorphisms in the zebu and gayal populations, respectively. Similarly, the average minor allele frequency value was as high 0.29 in zebu and as low as 0.09 in gayal. The mean expected heterozygosity varied from $0.42{\pm}0.14$ in zebu to $0.148{\pm}0.14$ in gayal with significant heterozygosity deficiency of 0.06 ($F_{IS}$) in the latter. Coancestry estimations revealed that the two zebu populations are weakly differentiated, with over 99% of the total genetic variation retained within populations and less than 1% accounted for between populations. Conversely, strong genetic differentiation ($F_{ST}=0.33$) was observed between zebu and gayal populations. Results of population structure and principal component analyses suggest that gayal is distinct from Bos indicus and that the two zebu populations were weakly structured. This study provides basic information about the genetic diversity and structure of Bangladeshi cattle and the semi-domesticated gayal population that can be used for future appraisal of breed utilization and management strategies.

Ovarian Response to Different Dose Levels of Follicle Stimulating Hormone (FSH) in Different Genotypes of Bangladeshi Cattle

Ali, M.S.,Khandoker, M.A.M.Y.,Afroz, M.A.,Bhuiyan, A.K.F.H. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.1

The experiment was conducted under the Department of Animal Breeding and Genetics, Bangladesh Agricultural University (BAU), Mymensingh from June, 2001 to December, 2005 in two different locations (Central Cattle Breeding and Dairy Farm and Bangladesh Livestock Research Institute in Savar, Dhaka) to observe ovarian response to different doses of FSH in three different genotypes of cattle- indigenous Local, Pabna cattle and Friesian${\times}$Local cross. Five different dose levels used were 200, 240, 280, 320 and 360 mg. Ovarian response as corpus luteum (CL), recovered embryo (RE) and of transferable embryos (TE) count in Local were significant for 320, 280 and 280 mg respectively. In Pabna cattle CL, RE and TE count were found significant for 360, 320 and 320 mg respectively. In Friesian${\times}$Local cross CL, RE and TE count were found significant for 360, 320 and 320 mg respectively. The excellent quality embryos showed significantly the highest yield ($1.80{\pm}0.20$) in the 240 and 280 mg FSH levels in Local genotype. In Pabna cattle, the highest yield ($2.00{\pm}0.32$) was found at FSH level 320 mg. In Friesian${\times}$Local, the highest yield ($2.20{\pm}0.20$) was found at FSH level 280 mg.

TRANSFERRIN POLYMORPHISMS AND GROWTH RATE IN RHODE ISLAND RED, CROSSBRED AND NATIVE CHICKENS

Zaman, S.,Ali, A.,Faruque, M.O.,Bhuiyan, A.K.F.H. Asian Australasian Association of Animal Productio 1991 Animal Bioscience Vol.4 No.3

Transferrin polymorphisms and growth rate up to 12 weeks of age were observed in RIR. crossbreds and native chickens. $Tf^{BB}$ genotype was observed in all types of bird. $Tf^{BC}$ occurred only in crossbred and native chickens. Frequency of $Tf^B$ was the highest in all types. Mean body weights at 8- and 12- weeks of age were the highest in RIR ($292{\pm}37.77$ and $612{\pm}75.69g$ respectively) and the lowest in natives for $Tf^{BC}$ ($180{\pm}11.54$ and $308{\pm}4.94g$ respectively). The difference in 12 week body weigh t of crossbreds between $Tf^{BB}$ and $Tf^{BC}$ was found to be significant (p<0.05). The results indicate that crossbreds ($Tf^{BB}$) may be grown effectively upto 12 weeks of age under Bangladesh conditions.