The genomic tool Clarifide Girolando allows the development of dairy herds that adapt to the climate stresses of different Brazilian regions. Brazil is a country with continental dimensions and large climate variations, which makes a single genetic standard impracticable for the entire territory. High temperatures and humidities interfere with milk production directly and represent one of the worst bottlenecks to the national dairy farming. The study followed 300 herds of the Girolando breed in different parts of the country and proved that losses due to heat stress reached more than a thousand liters of milk per lactation period. Genomics offers farmers the chance to establish an economically viable and increasingly more efficient breeding system. In parallel, it adds value to the Brazilian breed Girolando. Clarifide Girolando, a result of a public-private partnership, was the first genomic assessment product for dairy herds in Brazil. Embrapa Dairy Cattle (has been using a genomic tool called Clarifide Girolando (see box below) to identify bulls that can produce progeny (offspring) according to tolerance to heat stress. "With it, we intend to tackle a big problem in dairy cattle farming, which is production loss caused by local conditions of high temperature and humidity", states the Embrapa researcher Marcos Vinícius Barbosa da Silva, who coordinates the research. "Heat stress interferes directly with milk production and the more productive the cow, the greater this interference will be", states Renata Negri, PhD in Genetics and Breeding from the Federal University of Rio Grande do Sul (UFRGS), who integrates the research team. She adds: "It is believed that there are differences in the physiological responses associated with milk production in the different genetic groups that constitute the Girolando breed, and so it is necessary to identify and classify the animals according to their heat tolerance". The research also counts on the participation of fellow PhDs in Genetics and Breeding Darlene Daltro (UFRGS) and Sabrina Kluska, from the São Paulo State University (Unesp-Jaboticabal). Daltro informs that the work recently begun in May, when 300 herds distributed in several points of the country were selected. The production of the individuals in such herds was followed and compared, using the local climate conditions recorded by the nearest weather stations as the main variable. Mathematical models demonstrated that some cows of the Girolando breed can be prevented from producing over a thousand liters, considering 305 days of lactation, due to heat stress. After that, through Clarifide, the genome of the animals surveyed was identified to determine the most adaptable to given regions. Genomics adds value to the Brazilian breed Girolando According to Kluska, with the research, artificial insemination centers will be able to determine not only the PTAs (Predicted Transmission Abilities) but also the progeny that most suits the diverse climate conditions of the country. According to her, this information is strategic for farmers. In addition to the fall in milk production, farms loose by discarding high-value animals that are not tolerant to heat stress but whose genetics could be very efficient in other places. "The identification of and within genetic groups will provide directions according to the local conditions of each Brazilian region, allowing breeders the choice and use of the animals according to actual management and environment conditions, in order to establish an economically viable and increasingly more efficient breeding system", highlights the scholar from Unesp-Jabuticabal. Silva says that the research will greatly contribute to Girolando, a synthetic breed developed in Brazil by crossing the breeds Holstein-Friesian X dairy Gyr, combining the high production potential of the former with the hardiness of the latter. "Brazil is a country with continental extension and large climate variations, so it is impracticable to have a single genetic standard for the whole domestic territory. Genomic knowledge has been allowing us to adjust the breed's characteristic according to specific characteristics of heat and humidity", Silva sums up. The researcher also underscores that this work is a partnership between Embrapa with the Brazilian Association of Girolando Breeders (Girolando). "We have set up a pool of resources to discover characteristics that are intrinsic to the nature of the animals of the breed, providing a better understanding of defense mechanisms and helping decision making and direction of the breeding and genetic improvement and breeding programs, according to selection goals, market requirements and animal welfare requirements", Silva adds. Launched three years ago, Clarifide Girolando has already shown results Clarifide Girolando is the result of a partnership formed by Embrapa, the Brazilian Association of Girolando Cattle Breeders, CRV Lagoa and Zoetis. In Brazil It was the first product for genomic assessment of dairy herds, whose aim is to select genetically superior animals. Its development took six years of research in genomics, molecular genetics and bioinformatics. “We have gathered what is most advanced in the knowledge of genomes and computational systems to assess the information from a chip with hundreds of thousands of data related to bovine DNA”, Silva states. The selection of superior animals for dairy production systems is made from a sample of biological material that contains the animal's cells. Collected genetic information is compared to the one available in Clarifide Girolando chip. As a result of this work, farmers receive a series of information regarding the animal, such as milk production and proteins, whether they bear genes that produce genetic disorders, reproductive capacity and other data required to have the process of herd breeding be effective, like the research about tolerance to heat and humidity. The reduced timelength for animal assessments, with subsequent cost reduction, is Clarifide Girolando's greatest advantage. Currently, a bull's selection for a progeny test costs about R$ 300,000. It is a long process, which can last about seven years. Clarifide Girolando optimizes that, as demonstrated by the research on heat stress, with the 300 selected flocks, that lasted only six months. Genomics and prediction: genetic selection before birth Genomic assessment opens up major possibilities for herd improvement. For instance, it allows the animal to be selected before it is born. It is possible to remove a small sample (ten cells) of an embryo seven days after the in vitro fertilization and, through such few cells, analyze its entire genome. If the embryo has desirable traits, it is transferred to the (surrogate) cow that will gestate it. Otherwise it can be discarded. Besides saving time, this procedure optimizes surrogate mothers, as the cow will only gestate the embryos that were previously selected as the best.