• Asian-Australasian Journal of Animal Sciences
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• 제30권5호
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• pp.603-621
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• 2017

The current review focuses on characterization and conservation efforts vital for the development of breeding programmes for indigenous beef cattle genetic resources in Southern Africa. Indigenous African cattle breeds were identified and characterized using information from refereed journals, conference papers and research reports. Results of this current review reviewed that smallholder beef cattle production in Southern Africa is extensive and dominated by indigenous beef cattle strains adaptable to the local environment. The breeds include Nguni, Mashona, Tuli, Malawi Zebu, Bovino de Tete, Angoni, Landim, Barotse, Twsana and Ankole. These breeds have important functions ranging from provision of food and income to socio-economic, cultural and ecological roles. They also have adaptive traits ranging from drought tolerant, resistance to ticks and tick borne diseases, heat tolerance and resistance to trypanosomosis. Stakeholders in the conservation of beef cattle were also identified and they included farmers, national government, research institutes and universities as well as breeding companies and societies in Southern Africa. Research efforts made to evaluate threats and opportunities of indigenous beef cattle production systems, assess the contribution of indigenous cattle to household food security and income, genetically and phenotypically characterize and conserve indigenous breeds, and develop breeding programs for smallholder beef production are highlighted. Although smallholder beef cattle production in the smallholder farming systems contributes substantially to household food security and income, their productivity is hindered by several constraints that include high prevalence of diseases and parasites, limited feed availability and poor marketing. The majority of the African cattle populations remain largely uncharacterized although most of the indigenous cattle breeds have been identified.

• Asian-Australasian Journal of Animal Sciences
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• 제28권7호
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• pp.911-921
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• 2015

At least 150 indigenous African cattle breeds have been named, but the majority of African cattle populations remain largely uncharacterized. As cattle breeds and populations in Africa adapted to various local environmental conditions, they acquired unique features. We know now that the history of African cattle was particularly complex and while several of its episodes remain debated, there is no doubt that African cattle population evolved dramatically over time. Today, we find a mosaic of genetically diverse population from the purest Bos taurus to the nearly pure Bos indicus. African cattle are now found all across the continent, with the exception of the Sahara and the river Congo basin. They are found on the rift valley highlands as well as below sea level in the Afar depression. These unique livestock genetic resources are in danger to disappear rapidly following uncontrolled crossbreeding and breed replacements with exotic breeds. Breeding improvement programs of African indigenous livestock remain too few while paradoxically the demand of livestock products is continually increasing. Many African indigenous breeds are endangered now, and their unique adaptive traits may be lost forever. This paper reviews the unique known characteristics of indigenous African cattle populations while describing the opportunities, the necessity and urgency to understand and utilize these resources to respond to the needs of the people of the continent and to the benefit of African farmers.

• Journal of Animal Science and Technology
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• 제57권12호
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• pp.47.1-47.10
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• 2015

Background: Knowledge of linkage disequilibrium (LD) levels among different populations can be used to detect genetic diversity and to investigate the historical changes in population sizes. Availability of large numbers of SNP through new sequencing technologies has provided opportunities for extensive researches in quantifying LD patterns in cattle breeds. The aim of this study was to compare the extent of linkage disequilibrium among Iranian cattle breeds using high density SNP genotyping data. Results: A total of 70 samples, representing seven Iranian indigenous cattle breeds, were genotyped for 777962 SNPs. The average values of LD based on the $r^2$ criterion were computed by grouping all syntenic SNP pairwises for intermarker distances from 0 Kb up to 1 Mb using three distance sets. Average $r^2$ above 0.3 was observed at distances less than 30 Kb for Sistani and Kermani, 20 Kb for Najdi, Taleshi, Kurdi and Sarabi, and 10 Kb for Mazandarani. The LD levels were considerably different among the Iranian cattle breeds and the difference in LD extent was more detectable between the studied breeds at longer distances. Lower level of LD was observed for Mazandarani breed as compared to other breeds indicating larger ancestral population size in this breed. Kermani breed continued to have more slowly LD decay than all of the other breeds after 3 Kb distances. More slowly LD decay was observed in Kurdi and Sarabi breeds at larger distances (>100 Kb) showing that population decline has been more intense in more recent generations for these populations. Conclusions: A wide genetic diversity and different historical background were well reflected in the LD levels among Iranian cattle breeds. More LD fluctuation was observed in the shorter distances (less than 10 Kb) in different cattle populations. Despite of the sample size effects, High LD levels found in this study were in accordance with the presence of inbreeding and population decline in Iranian cattle breeds.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8호
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• pp.1069-1076
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• 2019

Objective: Yunnan is not only a frontier zone that connects China with South and Southeast Asia, but also represents an admixture zone between taurine (Bos taurus) and zebu (Bos indicus) cattle. The purpose of this study is to understand the level of genomic diversity and the extent of admixture in each Yunnan native cattle breed. Methods: All 120 individuals were genotyped using Illumina BovineHD BeadChip (777,962 single nucleotide polymorphisms [SNPs]). Quality control and genomic diversity indexes were calculated using PLINK software. The principal component analysis (PCA) was assessed using SMARTPCA program implemented in EIGENSOFT software. The ADMIXTURE software was used to reveal admixture patterns among breeds. Results: A total of 604,630 SNPs was obtained after quality control procedures. Among six breeds, the highest level of mean heterozygosity was found in Zhaotong cattle from Northeastern Yunnan, whereas the lowest level of heterozygosity was detected in Dehong humped cattle from Western Yunnan. The PCA based on a pruned dataset of 233,788 SNPs clearly separated Dehong humped cattle (supposed to be a pure zebu breed) from other five breeds. The admixture analysis further revealed two clusters (K = 2 with the lowest cross validation error), corresponding to taurine and zebu cattle lineages. All six breeds except for Dehong humped cattle showed different degrees of admixture between taurine and zebu cattle. As expected, Dehong humped cattle showed no signature of taurine cattle influence. Conclusion: Overall, considerable genomic diversity was found in six Yunnan native cattle breeds except for Dehong humped cattle from Western Yunnan. Dehong humped cattle is a pure zebu breed, while other five breeds had admixed origins with different extents of admixture between taurine and zebu cattle. Such admixture by crossbreeding between zebu and taurine cattle facilitated the spread of zebu cattle from tropical and subtropical regions to other highland regions in Yunnan.

• Genomics & Informatics
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• 제10권3호
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• pp.200-205
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• 2012

Although a large number of single nucleotide polymorphisms (SNPs) have been identified from the bovine genome-sequencing project, few of these have been validated at large in Bos indicus breeds. We have genotyped 192 animals, representing 5 cattle populations of Ethiopia, with the Illumina Bovine 8K SNP BeadChip. These include 1 Sanga (Danakil), 3 zebu (Borana, Arsi and Ambo), and 1 zebu ${\times}$ Sanga intermediate (Horro) breeds. The Hanwoo (Bos taurus) was included for comparison purposes. Analysis of 7,045 SNP markers revealed that the mean minor allele frequency (MAF) was 0.23, 0.22, 0.21, 0.21, 0.23, and 0.29 for Ambo, Arsi, Borana, Danakil, Horro, and Hanwoo, respectively. Significant differences of MAF were observed between the indigenous Ethiopian cattle populations and Hanwoo breed (p < 0.001). Across the Ethiopian cattle populations, a common variant MAF (${\geq}0.10$ and ${\leq}0.5$) accounted for an overall estimated 73.79% of the 7,045 SNPs. The Hanwoo displayed a higher proportion of common variant SNPs (90%). Investigation within Ethiopian cattle populations showed that on average, 16.64% of the markers were monomorphic, but in the Hanwoo breed, only 6% of the markers were monomorphic. Across the sampled Ethiopian cattle populations, the mean observed and expected heterozygosities were 0.314 and 0.313, respectively. The level of SNP variation identified in this particular study highlights that these markers can be potentially used for genetic studies in African cattle breeds.

• 대한수의학회지
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• 제52권4호
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• pp.231-238
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• 2012

The expression profiles of inflammatory cytokines viz. interleukins (IL)-6, IL-8, IL-12, granulocyte macrophage-colony stimulating factor, interferon-${\gamma}$ and tumor necrosis factor-${\alpha}$ in response to subclinical mastitis in indigenous cattle breed Kankrej (n = 6), Gir (Bos indicus) (n = 12) and crossbred (Bos taurus${\times}$Bos indicus) (n = 7) were investigated using quantitative real time PCR. Significant correlation (p < 0.05) was observed between total bacterial load and somatic cell count (SCC) in all three breeds of cattle. All the cytokines were observed to be up-regulated compared to cows with healthy quarters, however, level of their expression varied among three breeds of cattle. In Kankrej most cytokines were found to be transcribed to higher levels than in other two breeds; the milk had higher load of bacteria but not so high SCC, implying that Kankrej has a higher inherent resistance against mastitis. The results of present study indicated that mammary glands of crossbred cattle are more sensitive to bacterial infection than indigenous breed of cattle as they elicit immune response at lower bacterial load and result into higher SCC. Research on identification of factors responsible for differentially expressed cytokines profiles and use of cytokines as immunomodulatory tools can pave way for formulating control strategies against bovine mastitis.

• Asian-Australasian Journal of Animal Sciences
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• 제17권9호
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• pp.1204-1209
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• 2004

Random amplification of polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis was carried out using DNA samples of 30 animals of Rathi cattle and 42 animals of Tharparkar cattle. Genomic DNA was isolated as per standard protocol and evaluated for its quality, purity and concentration. Twenty three random primers were screened out of which 15 primers yielded satisfactory amplifications and were used for further analysis. Average numbers of polymorphic fragments per primer were 7.07${\pm}$0.86 in Rathi and 6.80${\pm}$0.61 in Tharparkar cattle. The percentage of polymorphic bands in these two cattle breeds were 86 and 87%, respectively. Within breed genetic similarities for pooled over primers in the animals of Rathi and Tharparkar breeds were .577${\pm}$0.30 and 0.531${\pm}$0.02, respectively on the basis of band frequency (BF) and 0.645${\pm}$0.04 and 0.534${\pm}$0.04, respectively on the basis of band sharing (BS). Averages of between breed genetic similarities for pooled over primers were 0.97 and 0.92 according to BF and BS, respectively, which reflect higher degree of genetic similarity between Rathi and Tharparkar cattle breeds. Index of genetic distance based on BF and BS for pooled over primers was 0.030${\pm}$0.011 and 0.088${\pm}$0.031, respectively. Percentage of polymorphic bands and within-breed genetic similarities on the basis of band frequency (BF) and band sharing (BS) for pooled over primers revealed higher genetic similarity in Rathi than Tharparkar cattle population. High estimates of between breed genetic similarities for pooled over primers indicated that either Rathi is having decent from Tharparkar or both the cattle breeds are having common descent. Low value of Index of genetic distances between these two cattle breeds may be due to the fact that Rathi and Tharparkar cattle breeds are the native of Thar Desert in Northwest India. The results of between breed genetic distances also confirm the existence of high degree of genetic similarity between these two breeds of cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.461-464
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• 1996

The data on milk yield of 1837 healthy dairy cows of different genetic groups raised in Central Cattle Breeding and Dairy farms, Savar, Dhaka for the period from 1978 to 1992 were analyzed from first to 6th lactation. The mean (SE) milk yields of 100 days, 305 days, total lactation and total life time ($928{\pm}48.6kg$, $2,188{\pm}201.81kg$, $2,661{\pm}385.46kg$ and $11,134{\pm}2,916kg$) respectively, were in pure bred Friesian found to be highest among all genetic groups. The corresponding means in indigenous cows, $334{\pm}12.92kg$, $946{\pm}64.44kg$, $635{\pm}16.31kg$ and $3,934{\pm}402.21kg$ were the lowest. Among the $F_1$, $F_2$ and $F_3$ cross-breds, the $F_1$ half bred Friesian showed the highest performance in milk yield. The half bred Friesian in successive generations yielded low milk. Similar trend was obtained incase of cross-bred with other breeds such as Jersey, Sindhi and Sahiwal. From the over all results, it can be concluded that the performance in respect to milk yield of pure bred Friesian and their $F_1$ half bred with indigenous and Sahiwal were superior over the $F_2$ or $F_3$ cross-breds between Fresian and any other breed irrespective of proportion of blood. The performance in respect to production of indigenous local cow was found to be almost similar with that of Sahiwal breed.

• Asian-Australasian Journal of Animal Sciences
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• 제13권1호
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• pp.60-67
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• 2000

A survey involving 71 cattle and buffalo farming households under coconut plantations was carried out in three districts (Pannala, Bingiriya and Kuliyapitiya) with the aim of assessing the status of livestock farming. Also, 24 households (eight from each district) were visited monthly for period of one year to collect information on feeding practices. Apart from milk, animals were reared for selling, draught, bio-gas and for manure. Due to difference in system of management of cattle and buffaloes, manure from buffaloes (46%) was more frequently used for coconuts than that from cattle (10%). Majority of cattle were improved breeds (temperate origin) or their crosses, as compared to buffaloes (mainly indigenous). The most predominant management system was tethered grazing during the day, and stall feeding during the night. Coconut land (own or others) and paddy fields were the major grazing areas for the animals. The grass from coconut land was lower in crude protein (8.2%) and digestibility (48%) compared to those from paddy fields (12.1 and 57%, respectively). Of the 288 rations analysed, grass was included in 280 of the daily rations for cattle as compared to 251 for buffaloes. Straw was more commonly included in mixed rations for buffaloes (137 out of 288) than for cattle (53 out of 288). The frequency of use of straw for buffaloes was high in Pannala (75 out of 137 cases). There was wide variation among the improved breeds of cattle and buffaloes in milk production (2 to 9 litres/day), lactation length (6 to 10 months) and calving interval (13-21 months).

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.613-619
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• 2005

Indigenous Yakutian cattle' adaptation to the hardest subarctic conditions makes them a valuable genetic resource for cattle breeding in the Siberian area. Since early last century, crossbreeding between native Yakutian cattle and imported Simmental and Kholmogory breeds has been widely adopted. In this study, variations at 22 polymorphic microsatellite loci in 5 populations of Yakutian, Kholmogory, Simmental, Yakutian-Kholmogory and Yakutian-Simmental cattle were analysed to estimate the genetic contribution of Yakutian cattle to the two hybrid populations. Three statistical approaches were used: the weighted least-squares (WLS) method which considers all allele frequencies; a recently developed implementation of a Markov chain Monte Carlo (MCMC) method called likelihood-based estimation of admixture (LEA); and a model-based Bayesian admixture analysis method (STRUCTURE). At population-level admixture analyses, the estimate based on the LEA was consistent with that obtained by the WLS method. Both methods showed that the genetic contribution of the indigenous Yakutian cattle in Yakutian-Kholmogory was small (9.6% by the LEA and 14.2% by the WLS method). In the Yakutian-Simmental population, the genetic contribution of the indigenous Yakutian cattle was considerably higher (62.8% by the LEA and 56.9% by the WLS method). Individual-level admixture analyses using STRUCTURE proved to be more informative than the multidimensional scaling analysis (MDSA) based on individual-based genetic distances. Of the 9 Yakutian-Simmental animals studied, 8 showed admixed origin, whereas of the 14 studied Yakutian-Kholmogory animals only 2 showed Yakutian ancestry (>5%). The mean posterior distributions of individual admixture coefficient (q) varied greatly among the samples in both hybrid populations. This study revealed a minor existing contribution of the Yakutian cattle in the Yakutian-Kholmogory hybrid population, but in the Yakutian-Simmental hybrid population, a major genetic contribution of the Yakutian cattle was seen. The results reflect the different crossbreeding patterns used in the development of the two hybrid populations. Additionally, molecular evidence for differences among individual admixture proportions was seen in both hybrid populations, resulting from the stochastic process in crossing over generations.