While animal products make large contributions to nutrition and the fight against poverty, they also entail outsized impacts on the climate and environment and assuring animal health is increasingly critical for human health, he said at the 10th Global Forum for Food and Agriculture in Berlin.
As demand for meat and other animal products grows robustly, especially in developing countries, the question of equity and efficient distribution grows in importance.
More than half the world's rural poor rely on livestock, and they must be provided with appropriate skills, knowledge and technologies to participate in and benefit from that expected growth rather than "pushed aside by expanding large capital-intensive operations," Graziano da Silva said.
Increased consumption of animal products will enhance nutrition, especially for younger children in developing countries whose cognitive and physical development requires crucial micronutrients such as zinc and iron he said, warning that excess consumption also poses risks. "We have to focus on healthy and balanced diets," he said.
He also noted that alternative sources of protein - such as fish and pulses - are available and should be explored.
As livestock generates more greenhouse gases than other food sources - around 14.5 percent of all anthropogenic emissions - the sector's expansion poses challenges to biodiversity, sustainable access to water and, notably, the goals of the Paris climate agreement's pledge to limit how high average global temperatures rise.
However, "a low-carbon livestock sector is possible to achieve," Graziano da Silva said, pointing to FAO estimates that methane emissions can quickly be cut by 20 to 30% across all production systems by the adoption of known husbandry practices such as regenerative grazing, forage selection and better recycling of nutrients and energy from livestock waste. Better management of pasturelands and the health and carbon-storing capacity of their soils is also essential for increased livestock production not to require further deforestation, he added.
"With improved and climate-smart practices, we can quickly put in place more sustainable and ‘greener' livestock supply chains," Graziano said. He urged to seize the opportunity after last year's climate summit in Bonn COP23 specifically indicated improved livestock management systems as a priority.
Graziano da Silva also focused on animal and human health issues, warning that "the emergence of diseases will likely intensify in the coming years, as rising temperatures favour the proliferation of insects." Zoonotic diseases with pandemic potential such as some strains of avian influenza "pose a big threat to people, animals and the environment."
FAO has a long track record in tackling transboundary animal diseases, including leading the successful eradication of rinderpest and a new global campaign to eradicate peste des petits ruminants.
FAO also recognises the need to tackle antimicrobial resistance (AMR), a major threat to human health that is exacerbated by the abuse, overuse and misuse of antibiotics in livestock, which globally consume three times more of such products than humans do.
The Director-General emphasised that FAO's recommendations are that the use of antimicrobial medicines to promote animal growth should be phased out immediately and that they should only be used to cure disease and alleviate unnecessary suffering, while their preventive use should be deployed only under strict circumstances. FAO is helping many countries develop and implement national AMR action plans, Graziano da Silva said.
