Surlier cows can emit almost 40% more enteric methane per kilo of milk than calmer ones. The finding came from research by Embrapa and the Federal University of Juiz de Fora. It verified that the most reactive cows directed 25.24% less net energy to lactation, while the calmest cows placed 57.93% more energy on milk production. The research was performed with the Girolando breed, the main dairy breed in Brazil. Combining the adoption of rational management with calm environments favors production and environmental sustainability. Temper interferes with cow metabolism and hence influences emissions of enteric methane, one of the main causers of the greenhouse effect. This is the conclusion of research led by Embrapa Dairy Cattle in partnership with the Department of Zoology at the Institute of Biological Sciences of the Federal University of Juiz de Fora (UFJF). Moreover, the research has demonstrated that cows whose temper is more reactive to human presence and to milking produce less milk. According to the researchers who led the work, climate change and productivity became two of the major arguments for the adoption of rational management, a practice that started to be successfully used by farmers who have cows of the dairy Gyr and Girolando breeds in their herds. “Another argument farmers who adopt the technique already know in practice is the improvement in animal management, facilitating the work of conducting the cattle, preventing accidents and the discarding of the most reactive cows”, reports the Embrapa researcher Mariana Campos, who coordinated the study at Embrapa's Multiuser Complex of Cattle Farming Bioefficiency and Sustainability, in Coronel Pacheco, MG. Greenhouse gas emissions and global warming have become a more pressing concern in the sector. Research by Embrapa and UFJF has shown that more reactive dairy cows can emit almost 40% more enteric methane per kilo of milk than calmer kine. The experiments that led to this conclusion are part of the PhD thesis in Biodiversity and Nature Conservation by Maria Guilhermina Pedroza. She explains that the study was performed with 28 primiparous Girolando cows (F1). All the animals were submitted to training for milking before calving and were observed both in the corral and during the milking. “We analyzed the temper of each individual, identifying the calmer and more reactive ones through behaviors like steps, kickbacks, and defecation and urination during the milking process and in the corral, and through indicators like animals' agitation in the cattle crush, speed as they exit the crush, and escape speed opposed to an unknown observer”, the PhD candidate explains. Milk production was also measured, and digestibility tests and respirometry (in respirometry chambers) showed that the most reactive cows channeled 25.24% less net energy to lactation, while the calmest, which ruminate more in the milking room, placed 57.93% more net energy on milk production. Mariana Campos (pictured on the left) says that the experiment is important for Brazilian dairy cattle farming due to the importance of the Girolando breed for domestic production. Girolando is a synthetic breed that was developed for tropical conditions by combining two breeds with different tempers: dairy Gyr and Holstein-Friesian. “The result of the crossing of those breeds brought forth a rustic animal with good milk production; however, they are more averse to milking. The training of heifers for the first milking is a technique that suits the dairy herds of Brazil due to use of crossbred or Zebu cattle. Professor Aline Sant'Anna, coordinator of the Ethology and Animal Welfare Research Team (Nebea) at UFJF who advised Maria Guilhermina in her thesis, reports that the animals' temper has an inheritable component, but environmental conditions also interfere in the cows' nature. Although the bovine breeding and genetic improvement programs have achieved a lot in that sense, rational management should be adopted in combination with a calm environment at the time of milking. “Although the genome influences each animal's character, it is possible to mold phenotypes through suitable environments”, the lecturer observes. The selection of calmer cows and the adoption of best management practices both the cows' and workers' welfare. As dairy companies have been working to neutralize the carbon emissions of the sector, the study has proven that the adoption of rational taming protocols and animal breeding focused on more docile animals can be important strategies to reach decarbonization targets. “Animals with more reactive tempers are undesirable for efficient and sustainable cattle farming,” Campos concludes. Reactive cow X calm cow After giving birth, some heifers demonstrate higher reactivity than others and the wasted energy results in lower milk production and higher enteric methane production, and also increases the risk of accidents. In the milking room, reactive cows or heifers characteristically: - urinate and defecate with higher frequency; - kick back; - tap their feet; - show agitation; - knock down the set of teat cup attachments; - present slower milking speed. In contrast, calmer cows facilitate handling and reduce their milking time. Their following characteristics are appreciated: - They are quieter during the milking procedure; - they spend more time ruminating; - they rarely urinate and defecate in the milking room; - they remain at the trough for longer.