Protection and Utilization of Yellow Cattle Breed Resources in China

Jia YAO, Dacai PENG

Ya’an Animal Husbandry Development Center, Ya’an 625000, China

Abstract Based on the general situation and genetic diversity of yellow cattle breed resources in China, this paper discusses the protection, development and utilization of Chinese yellow cattle breed resources, in order to provide reference basis for the development, utilization and sustainable development of local yellow cattle breeds in China.

Key words Yellow cattle, Breed resources, Protection, Utilization

1 Introduction

In recent years, with the rise of modern cattle industry in China, a large number of foreign cattle breeds have been introduced for crossbreeding, which has impacted the domestic yellow cattle breeds, and many valuable genes will be lost. Therefore, how to take the development and utilization of Chinese yellow cattle as the driving force to protect the breed resources of yellow cattle in various regions is the primary task for contemporary animal husbandry workers. Based on the general situation of breed resources and genetic diversity of yellow cattle in China, this paper discusses the protection, development and utilization of breed resources of yellow cattle in China, in order to prepare genetic materials for the cultivation of new strains of specialized beef cattle in China.

2 Breed resources of yellow cattle in China

Since the founding of the People’s Republic of China, as many as 27 cattle breeds have been introduced, including 9 dairy breeds—Holstein (Soviet Black and White, American Holstein, Friesland of the Netherlands, Holstein of Germany,etc.), Swiss Brown (Soviet Union, Swiss, American), Ala-Tau cattle, Kostroma cattle, red Danish cattle, milking shorthorn, Simmental cattle, Ayrshire cattle, and Jersey cattle. The Chinese breeds that have been successfully cultivated are Chinese Holstein, Chinese Simmental, Xinjiang Brown cattle, San-he cattle and Grassland Red cattle. Holstein cattle holds more than 90% of milk production capacity, and it is also mostly cultivated breed in other semi-agricultural and semi-pastoral areas, where the conditions are poor, but the demand for meat is high. From the perspective of diversity of dairy cow breeds, China should learn from the countries of the European Union. Simmental, Xinjiang brown cattle, San-he cattle and Grassland red cattle should be further developed. In particular, Simmental cattle in the mountains have an average milk yield of 7 100 kg, and Sichuan cattle used for milking and for meat in Xuanhan County have an average milk yield of 3 889 kg, with an average milk fat rate of 4.32%, a strong milk flavor and some southern characteristics. It can resist high temperature and high humidity and adapt to extensive management in rural areas. For this kind of population to be developed, it is suggested that the state should set up a project to strengthen the utilization and demonstration of excellent germplasm so as to promote the development of rural economy.

As many as 21 beef cattle breeds have been introduced, including short horned beef cattle, Lincoln red cattle, Simmental beef cattle, Charolais cattle, Limousin cattle, Angus cattle, Heyford cattle, German yellow cattle, South Devon cattle, Piemontese cattle, Chianina cattle, Belgian blue and white cattle, Droughtmaster cattle, Santa Gertrudis cattle, Murray grey cattle, Brahman cattle, Lowline cattle, Korean yellow cattle, and Kuroge Washu cattle. Among them, Simmental cattle, Charolais cattle, Limousin cattle, German yellow cattle, Angus cattle, South Devon cattle, Piemontese cattle, Belgian blue and white cattle play a leading role in the hybridization. In particular, the beef production of hybrid cattle of the first five breeds in the province accounts for about 76% of the total beef production in the country.

The number of local yellow cattle breeds has increased by 24 in this year’s supplementary survey. Among these breeds, except the above-mentioned Dangjiao cattle and Dengchuan cattle which became extinct as early as the end of 1980s, Diqing cattle, Ganzi Tibetan yellow cattle, Apeijiaza cattle, Lhasa yellow cattle and Tibetan cattle are closely related to each other, and genetic marker technology is needed for classification research. For example, the lineage difference between Chaidamu yellow cattle and Anxi cattle in the Mongolian cattle system should also be analyzed. A new round of research on the relationship between Weizhou yellow cattle and Leiqiong cattle, Xuzhou yellow cattle and Luxi yellow cattle should also be carried out under the guidance of systematic conservation theory.

3 Genetic diversity of Chinese yellow cattle

The genetic diversity of cattle breed resources can be detected at three levels, including individual, cellular and molecular levels. There are several methods, such as morphology, serum protein (enzyme), chromosome typing, DNA and mitochondria. Wang Yuyingetal. (1991) studied the relationship between blood protein polymorphism of some Chinese yellow cattle and the heredity. Yu Ruliangetal. (1993) used G-banding, C-banding, RBA-banding, conventional and C-banding or RBA-banding continuous staining techniques to study the two ancient breeds of Qinchuan cattle and Jinnan cattle, and it was found that Qinchuan cattle and Jinnan cattle had both proximal (or subproximal) and submetacentric Y chromosomes, showing heterozygosity.

With the development of molecular biology, genome project and the emergence of new molecular detection methods, the genetic marker methods used to study DNA polymorphism are developing rapidly. Molecular genetic markers were developed in the 1980s to analyze the diversity of genomic DNA, including microsatellite polymorphism analysis, restriction fragment length polymorphism (RFLP), amplified fragment length polymorphism (AFLP), randomly amplified polymorphic DNA (RAPD), single nucleotide polymorphism (SNP) and DNA sequencing.

At present, microsatellite polymorphism analysis is widely used. Ma Yuehuietal. (2003) analyzed the genetic structure of Yanbian cattle, Nanyang cattle, Simmental cattle, Piemontese hybrid cattle and Korean cattle using four microsatellite loci. The results showed that the polymorphism of Yanbian cattle and Korean cattle was relatively low, and the diversity of Simmental and Piemontese hybrids was significantly lower than expected, indicating the existence of selection and inbreeding. Zhong Jinchengetal. (2006) used 9 microsatellite markers to study the genetic diversity and classification of some Chinese yak breeds, including Maiwa yak, Jiulong yak, Datong yak and Tianzhu white yak. The results showed that there was rich genetic diversity among and within microsatellite loci of Chinese yak breeds. Five yak populations were divided into two groups, Jiulong yak was a single group, and other yak breeds were clustered into one group.

It should be pointed out that although new technologies and analytical methods are still emerging, there is no one that can completely replace other methods. Any detection method has its own advantages and limitations in theoretical or practical research. In the diversity analysis of livestock and poultry genetic resources, there are various methods, including traditional morphology, cytology, isozyme and DNA techniques. If only one analytical technology is used, no matter how advanced the technology is, it can only reflect one aspect of the situation. Therefore, only by a comprehensive analysis and evaluation of resources, especially some traditional analysis methods, can it fully reflect the true panorama of a resource.

4 Protection of cattle breed resources

For the protection of cattle breed resources, breeding should focus on economic traits, breed characteristics and ecological adaptability. In the process of cattle resource protection, breed conservation can not be completely random, and attention should be paid to the combination of breed conservation and breeding. In the process of conservation, the breeding of conservation population should also be strengthened, with emphasis on maintaining the excellent traits of cattle breed resources in production, reproduction, stress resistance and adaptability, so as to achieve character protection and ensure the continuation of the gene pool of excellent resources.

It is necessary to combine the conservation of species with the development of cattle resources. The protection of cattle breed resources is a public welfare activity that is costly and benefits future generations, and the state can not uniformly protect all the resources. Therefore, it is necessary to mobilize the enthusiasm of provincial, regional, municipal, county departments, encourage them to develop local cattle resources, and realize the development and conservation of resources. The state only selectively protects some important endangered resources, establishes a conservation system at the national and local levels, expands the intensity and scope of resource conservation, and improves the quality of conservation. At the same time, it is necessary to mobilize the funds and strength of the whole society, promote enterprises and individuals to join in the protection and development of resources, and strive for funds and strength for species conservation through various channels.

The genetic evaluation data of resources should be actively used for reference in the work of species conservation. At present, many scientific research institutions and universities have carried out the evaluation of local breed resources and made a lot of progress. It is suggested that these results should be applied to the practical work of breed protection, and the evaluation data on the cellular and molecular level should be used as reference data for species conservation, so as to promote the work of species conservation and improve the quality of species conservation.

New techniques and methods for breed protection should be developed. At present, the preservation of cattle resources is mainly based on living body protection, which is costly and requires a lot of manpower and material resources. It is suggested to develop some new techniques and methods for resource preservation, such as cryopreservation of gametes or embryos and DNA preservation. In addition, somatic cell preservation is also a promising way. The Beijing Institute of Animal Husbandry and Veterinary Medicine of the Chinese Academy of Agricultural Sciences has built the world’s largest somatic cell bank of cattle resources, which has opened up a new way for the long-term preservation of cattle genetic resources, and is more suitable for cooperating with large enterprises in the future, combining development and protection.

It is suggested to increase the support for the basic research of cattle resources. With the acceleration of the commercialization of livestock and poultry breeds, the cattle breeds raised in developed countries and even all over the world are becoming increasingly simplified, and the genetic basis of cattle is gradually narrowed. Our government also attaches great importance to this problem and has carried out the protection of cattle breeds. But in the new era, the plunder of cattle resources has become the plunder of genes with excellent traits. It is suggested that the state should set up a special project to support the basic research on cattle breed resources and give it long-term support as a key point.

5 Utilization of cattle breed resources

Local improved yellow cattle in China have a series of advantages, such as small size, which is equivalent to medium and small physique internationally. Its feeding cost is low and it is resistant to crude feed. It is not easy to give birth unless the calf of the introduced breed is too heavy at birth. The lactation performance of local breeds of cattle in China is generally very low, and the growth is slow, resulting in a low rate of cattle delivered to the slaughterhouse. The paternal and maternal lines must be combined reasonably to improve the milk performance of the binary hybrid offspring. This is good for the next round of crossbreeding and produces higher benefits. Therefore, the crossbred cows with strong lactation ability should be retained as the pillar to improve the economic benefit of the breeding base.

The situation of hybrid and improved varieties is as follows:

Simmental has the characteristics of strong physique, toleration of crude feed, docile temperament, strong adaptability, high feed utilization rate, good meat quality and so on. After crossing with Chinese yellow cattle, the growth of hybrid offspring is fast, and the milk yield of hybrid cows is doubled, which can provide a good maternal line for the next round of crossbreeding, and it is the preferred male parent breed for improving Sichuan yellow cattle. The hybrid male calf is used in the production of beef cattle and the hybrid cow is used as the matrilineal breed for the production of three-way crossbred beef cattle. Simmental cattle can also be used as a paternal breed to improve the crossbreeding of Sichuan yellow cattle and cultivate our own cattle used for milking and for meat.

The color of Simmental hybrid cattle is mainly yellow (red) and white, and the distribution of spots becomes neat with the increase of band number, with white stars or white spots on the forehead and white patches in different sizes in the lower part of chest and abdomen. The head is moderate in size, the mouth is wide and the eyes are big, and the craniocervical junction is good. The back is straight, the rump is flat and the buttocks are wide, and the muscles are well-developed. The body is long, the limbs are stout and strong, and the temperament is gentle. Under the condition of extensive feeding in rural areas, the birth weight of Simmental hybrid cattle is 22.5 kg and the adult weight is 428.7 kg, 56.3% and 40.4% higher than that of local yellow cattle, respectively. After 13 months of fattening, the body weight and carcass weight of the first-generation male calves of Simmental hybrid cattle (7 months old) can reach 425.5, 247.8 kg, respectively, with slaughter rate of 58.01%, net meat percentage of 48.5%, high quality meat percentage of 34.49%. Simmental hybrid calves (4.7 months old) are fattened after 395 days, the body weight at the age of 17.8 months reaches 440.5 kg, the slaughtering rate is 58.3%, and the meat percentage is 49%.

Before 3 months of age, the growth and development of the first generation Piemontese hybrid cattle is not as fast as that of Xianan hybrid cattle, but faster than that of Nanyang cattle. The growth and development of the first generation Piemontese hybrid cattle is faster than that of Xianan hybrid cattle and Nanyang cattle after weaning. Through measurement and analysis, it is found that the body size and body weight of Piemontese hybrid cattle are equal to or greater than those of Xianan hybrid cattle in the later stage. Piemontese hybrid has a higher growth and development rate and is 25.50%-90% heavier than Nanyang cattle in all age groups, and the effect is very obvious. Moreover, the meat performance of Nanyang cattle is also greatly improved. On the premise of maintaining the excellent characters of Nanyang cattle, the meat quality and meat yield of hybrid offspring are significantly improved.

Charolais cattle is a large beef breed, and Charolais F1cattle is obviously inclined to the excellent traits of male parents and shows a good meat type. Its head is thick and short, the forehead is wide, the strength is great, the chest is wide, and the body is well ribbed-up. The back is straight, the physique is strong, and the muscles are compact. The hindquarters are well developed, the limbs are stout, the hoof is solid and the hair color is white, and it has a good body shape.

Limousin’s advantages lie in fine muscle fiber, uniform distribution of intermuscular fat, good tenderness of meat, but it has slow growth and poor lactation ability. It can be used in the second or third crossbreeding, and the difficult delivery rate of offspring is low. In China, Limousin’s coat color is very close to that of yellow cattle and is very popular, and we can also get a good result of crossbreeding between it and Charolais or Simmental.

The artificial insemination of frozen semen of Hereford cattle has obvious effect on the improvement of Dabieshan yellow cattle, and the growth and development indexes of F1generation have been significantly improved, with strong adaptability and high survival rate. The improvement method is simple and cost-effective (there is no need to buy and raise stud bulls), so it is worth further popularizing.