April 2007 Vishwa Go-Sammelan (World Cow Conference)
by Raghaveshwara Bharathi Swamiji, Shankaracharya Shri Ramachandrapura Mutt,Hosanagara KARNATAKA
Lecture delivered by Brazilian experts.
VERNEQUE, R.S., TEODORO, R.L., PEIXOTO, M.G.C.D., LEDIC, I.L., MACHADO, M.A. 2007. Programa Nacional de Melhoramento do Gir Leiteiro. Sumário Brasileiro de Touros. Resultados do Teste de Progênie Maio 2007. Juiz de Fora, MG. EMBRAPA-CNPGL, 56 p. EMBRAPA-CNPGL. Documentos, 118
Roberto Luiz Teodoro1,2 , Rui da Silva Verneque1,2 Maria Gabriela C.D. Peixoto1
1 Researcher of Embrapa Dairy Cattle - Rua Eugênio do Nascimento, 610 – Bairro Dom Bosco 36.038-330 Juiz de Fora – MG, Brazil, rteodoro@cnpgl.embrapa.br
2 CNPq scholarships,
Introduction
During the first four centuries of Brazil’s history, cattle breeding was developed with the use of European cattle (Bos Taurus). Taurus), originated from temperate weather countries. However, at the tropics, weather characteristics and management are very special, leading to a condition of stress to these animals, which could lead them to a decrease in production and even death. Only from the middle of the last century, producers learned not to fight against nature, getting from India the Zebu cattle (Bos taurus indicus), which nowadays occupies the largest part of our continental country. Then, in a few years the Zebu did what the European cattle were not able to do in many centuries: to adapt naturally to the adverse conditions of the Brazilian tropics.
The extraordinary development of Brazil’s bovines, particularly in Central, Northern and Northeastern Brazil, was mainly due to the introduction of the Indian breeds. Zebu animals reinvigorated the existing degenerated cattle, introducing the lacking rusticity to the specialized bovine of European origin, through crossings, allowing them to survive, reproduce and, mainly, to produce at the predominant management conditions. It is estimated that Brazil imported around 800,000 bovines of Europeans breeds, against only 6,000 of the Zebu breeds. Nevertheless, it is also estimated that nowadays around 80% or more of the Brazilian bovine has genes of the Zebu breeds in their genetic composition, demonstrating its importance in the development and improvement of the national herd of cattle
.
Under a scientific vision we thought that the better way to preserve and save the Zebu cattle in Brazil was to improve it for milk production and its contents, looking also for its welfare and comfort.
Brazil is now an important center of cattle raising and selection some Zebu breeds, occupying a good place in the ranking not only quantitatively but, mainly due to high quality level of the cattle, which is a response to the critical work of selection and improvement, specially inside the farms. Nowadays it continues through consolidated national programs, which intend to do the improvement of these breeds. In the beginning of the Zebu importation some animals were brought from Africa, but it was at India that the pioneers of our cattle raising found animals from different Zebu lineages, classified according to their features, functions and utilities, which after crossing with native cattle in Brazil showed to cattle breeders the solution of the majority of their problems. Among the introduced breeds the ones who predominated were Nelore (originated at Ongole), Gyr and Guzerá (originated at Kankrej), followed by Sindi and Kangayan. The Nelore, Gyr and Guzerá breeds were initially explored mainly for the meat, the former being the most predominantand hence occupying a large share of the national raising cattle herd.
The Gyr breeds, and recently the Guzerá breed, have been undergoing, in the last decades, an intensified process of selection and improvement for milk production through programs of progeny test and multiple ovulation and embryo transfer nuclei (MOET). The Sindi breed, which has low numeric expression but a high potential for milk production, has been raised in small nuclei mainly at the Northeast region of Brazil, a very dry region of our country. Very few farms has also started to work recently with Nelore cattle for milk production. The Gyr breed is explored mainly for milk production in India. According to Ledic (1995), when introduced in Brazil this breed was selected for meat production, showing later a lower efficiency in comparison to other Zebu breeds under our environmental conditions. However, it showed potential for milk production and at the 1930’s several herds of this breed were formed. The selection for milk production in Gyr has coming since this time. In 1985 it was established the progeny test for this breed involving a few number of breeders under supervision and technical coordination of Embrapa, from the Brazilian government. The first results from sire evaluations were reported in 1993. .
* adjusted to the adult age (between 7 and 8 years old)
This program started with only ten young sires at the first year, increasing this number each year and now we are testing 30 sires a year. These young sires, sons of the best cows and proved bulls are tested in collaborating farms, where are produced their progenies. They are tested for milk production and its content, as fat and protein milk, lactose and total solids since the market at nowadays is just paying for them. Until now, 161 bulls were proved for these traits and around 140 more bulls are in test (Verneque et al., 2007). Almost 50,000 lactation records form the data bank of this breed. At the begin the mean of milk production was around 2,300 kg per lactation and now it is around 2,800 kg, with 290 days of lactation length, in the Gyr population. It was due mainly the selection but also due to the improvement of the management, what it is also important. The market of Gyr semen increased almost 563% in this period, coming from 70,000 dosis sold in 1992, with the first results of the progeny test, to almost 600,000 dosis sold in the last year. It represents the success and acceptability of the program for the breeders in Brazil and Latin America.
2.2. Kankarej
In India the Kankrej breed, equivalent to Guzerá in Brazil, is used for milk production and traction work due to its bulk. In Brazil, since its introduction, it has been used for milk and meat production, although the selection for milk production has intensified only at the beginning of the 1990’s. In 1994 the progeny test for milk was initiated and also a program at the open MOET selection nucleus for milk production. The productive performance of these animals is presented in Table 2.
The progeny test here, similar to the Gyr program, has proved until now 45 young bulls with other 35 in testing (Teodoro et al., 2007). The MOET (multiple ovulation and embryo transfer) nuclei breeding system consists of a nuclei herd with the best animals available across all herds, in which the MOET technique is used intensively to promote selection. Contemporary families are formed with at least three females and a male. A very important factor to be considered in this system is the high genetic initial lift that can be obtained. Once the initial generation is formed by a small number of elite animals, there will be a high genetic superiority of these animals in relation to the basic population. In developing countries, where there are difficulties in introducing conventional systems for progeny tests, since neither artificial insemination nor milk control are applied at the ideal frequency, the concentration of financial, human and animal resources at MOET nuclei can allow the use of current technologies (Smith, 1988). Considering this information, a MOET nuclei for selection of the Guzerá breed was introduced in 1994 at “Taboquinha” Farm, located in the district of Itambacuri, in Minas Gerais state. This was a farm with good facilities for field evaluation of progenies produced by CENATTE (Center of Technical Assistance and Embryos Transference) from the elite cows selected for milk yield. This work is also carried out in association with Guzerá breeders and with technical assistance by the Brazilian Center of Guzerá Improvement (CBMG), the Association of Guzerá Breeders from Brazil (ACGB), the Veterinary School of UFMG and Embrapa Dairy Cattle Research Center. Fifty two families with a total of 105 young males were proved in the MOET nucleus with the results being more faster than the progeny test that spend about six to seven years for proving a bull.
A recent study of the genetic trend for this population since at the begin of the program shows a genetic gain about six kg of milk per year and the double of gain only in the MOET population, showing the advantage for using these technology, associated with the Progeny test.
2.3. ONGOLE
Although in Brazil the Nelore breed, or Ongole, has been selected for meat production, a number of animals have been selected for milk since the 1970’s. Dairy Nelore’s selection has begun in 1972 at the Calciolândia Farm, also in Minas Gerais state. The breeder, who selects Nelore for extensive raising, Gyr and Guzerá for milk production, observed that the milkers regularly milked some Nelore cows for milk consumption of their families. Thus he decided to form a herd of these animals selected among the progenies with potential for milk production.
For starting this study, they selected cows which presented well developed udders, more prominent mamarial veins and better raised calves. Once identified, these cows passed through a process of domestication and milking, and were monthly submitted to the official dairy control. Those cows with milk production greater than 1,200 kg at the end of the lactation were then selected and their progeny used, either as bulls or as cows.
The breeding stock always increased from the search for cows with dairy traits. It is important to mention that the selection of cows with potential for milk production varied from 2 to 4%, meaning that a minimum of two in 100 young cows were incorporated to the dairy breeding stock due to a good lactation (greater than 1,200 kg).
Besides selecting cows with potential for milk production within the herd, since 1983 some cows were bought from other breeders This practice, which still takes place nowadays, allowed the incorporation of new lineages into the breeding stock. Table 3 shows the evolution of the selection for more than 25 years.
Table 3. Number of calvings, average for productive and reproductive traits for Nelore breed, selected for milk production.
Table 4 shows averages for some productive and reproductive traits for cows alive presently. It is interesting to observe that, in general, lactation length is about eight months and the average daily yield is 7.8 kg. The calving interval is lower than 15 months and the age at first calving is three years and three months. Milk yields about 5,000 kg are also observed, showing a genetic potential for milk production.
2.4. RED SINDHI
The Sindi breed, descended from Paquistan but also easily found in India, was introduced in low numbers at the beginning of this century in Brazil, together with the other zebu breeds. Animals of this breed are in general small, have a good milk production and are well adapted for regions with adverse environment and difficulty for handling large animals. This breed presents some racial characteristics very similar to the Gyr breed, which possibly occasioned its absorption into the large Gyr population. Nowadays few nuclei of the breed are still kept, apparently pure, in several Brazilian regions mainly at the Northeast and the North ones. Some cattle breeders, independently, technically accessorized by Embrapa Dairy Cattle, keep some sort of data control of their animals, including milk production, reproduction and measures of racial conformation, in order to better recognize its potential and to genetically evaluate it as pure or crossbred, multiplying and spreading it into regions which better raising conditions, mainly at Brazil’s Northeast. Table 5 shows averages for some traits of the production and reproduction for the Sindi breed, obtained in two different herds, both at Paraíba State, Northeast region. Genetic evaluations of these animals have been carried out by the Embrapa Dairy Cattle with the purpose of identifying those animals which are superior, and hence could be intensively breed.
Table 5. Productive and reproductive performance of Sindi cows at Northeastern region of Brazil.
Trait Number of observations Mean Maximum
Milk yield at 305 days *(kg) 446 2,299 6,589
Milk yield per lactation * (kg) 446 2,235 7,253
Lactation length (days) 446 275 457
Age at first calving (months) 143 37.6 59.8
Calving interval (days) 253 459 725
* Adjusted to the adult age
3. Impact of the Zebu in the Brazilian dairy cattle
The Zebu has been intensively used in crossings with European breeds resulting in animals with a good productivity in the majority of the productive systems prevailing in Brazil. However, when selected for milk production it was verified that pure zebu has responded to the improvement of management and to the selection process. Due to the small population under selection, the biggest impact that these breeds can have on the national dairy cattle is as a genetic material supplier, mainly as source of semen from tested bulls. It is also possible to increase the female reproductive efficiency through embryos transfer (TE) and “in vitro” fertilization (FIV), generating a higher number of progenies from superior cows. It is important however, that animals sampled in these works should be selected based on traits of economic importance and not only based on their morphological characteristics.
4. References
LEDIC, I.L.1995. O Gyr Leiteiro. DBO Rural, v,14, n.181, p.113-132.
SMITH, C. 1988. Genetic improvement of livestock, using nucleus breeding units. World. Anim. Review., v.65, p.2-10.
VERNEQUE, R.S., TEODORO, R.L.;; PEIXOTO, M.G.C.D. 2007. Programa Nacional de Melhoramento do Guzerá para Leite: Resultados do Teste de Progênie, do Arquivo Zootécnico Nacional e do Núcleo MOET. Juiz de Fora, MG. EMBRAPA-CNPGL, 28p. EMBRAPA-CNPGL. Documentos, 119.
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