Sustainable livestock farming

Integrated Crop-Livestock Systems are nature-inspired food production systems, seeking sustainable intensification. They count on diversity and nutrient cycling to deliver ecosystem services, although their current fertilization practices follow a conventional per crop basis. Scientists Farias et al. evaluated several systems growing soybean in rotation with pastures for sheep. They showed that adopting a system fertilization strategy and integrating crops with livestock saved on fertilization, thereby decreasing costs and pollution while retrieving autonomy at the farm level.

Improved tropical forages include annual/perennial grasses, herbaceous/dual-purpose legumes, and multipurpose trees/shrubs. They have been promoted in Sub-Saharan Africa to address food scarcity limiting smallholder livestock productivity. Scientists Paul et al. reviewed 72 studies, demonstrating tropical forages’ multiple benefits on livestock and food crop productivity, household income, and soil quality.

Animal stocking rate on natural grasslands is a key factor determining livestock system productivity. In Uruguay, scientists Díaz et al. analyzed how beef cattle producers decide on stocking rates, in particular, those exceeding carrying capacity. They showed that management is affected by system configurations, mainly rigidity, poverty and by economic opportunity. They propose a framework to identify barriers and traps as a first step towards increasing the Uruguayan livestock system sustainability.

Spiders provide important ecosystem services and reflect the impacts of land-use intensification. In the Brazilian subtropics, scientists Freiberg et al. found that low grazing intensities increased pasture ground spiders’ abundance and richness in a soybean-livestock farming system. Hence, by adjusting grazing intensity in pastures, farmers can promote and diversify the spider communities.

The sustainability of genetic improvement programs in developing countries depends on breeders’ participation. Scientists Camara et al. evaluated the motivations of breeders and the factors influencing their participation in the N’Dama cattle-breeding program in Senegal. They found that social, family and institutional relationships are factors as important -as distance or production systems features.

Comparing five highly efficient and contrasted sheep farming systems across France and Ireland, scientists Benoit et al. showed that optimization of fodder self-sufficiency strategy led to the best economic and environmental performances, while also reducing feed/food competition. However, these systems do not fully fit with the meat industry demand for a regular lamb-meat supply throughout the year and lamb conformation.

Sustainably intensifying smallholder farming systems on sandy soils is critical to the development of livelihoods in the Mekong region of Cambodia and Laos. Scientists Philp et al. recently reckoned that forages could intensify livestock production in rainfed lowland rice farming systems. Varieties must be adapted to both flooding and drought. Furthermore, soil acidity, low soil fertility, drought and the continual removal of nutrients in harvested forage must be carefully managed.

In southern Brazil, pastures with mixed oat/ryegrass during winter are directly planted with soybean in summer. Scientists Peterson et al. found that pastures grazed by beef cattle during winter exhibited drier soil in the following summer. However, soybean productivity was unchanged. Long term crop-livestock integration induces unique synergies which need to be considered to ensure the sustainability of these systems.

In integrated crop-livestock systems, cover crops provide food for grazing animals but the intensive grazing of the cover crops can increase weed emergence. Scientists Schuster et al. showed that optimizing forage allowances in a grass cover crop grazed by cattle during winter, followed by no-tillage soybean production next summer, suppressed weeds and improved beef and soybean productions.