INRAE, Université Clermont Auvergne, Vetagro Sup, UMR Herbivores, 63122 Saint-Genès-Champanelle, France.
INRAE, Université Clermont Auvergne, HERBIPOLE, 63122 Saint-Genès-Champanelle, France.
Animal. 2023 Apr;17(4):100759. doi: 10.1016/j.animal.2023.100759. Epub 2023 Mar 7.
Combining several animal species to optimise the performance of the whole farming system is one of the core tenets of agroecology. Here, we associated sheep with beef cattle (40-60% livestock units (LU)) in a mixed system (MIXsys) and compared its performances to those of a specialised beef cattle-only system (CATsys) and a specialised sheep-only system (SHsys). All three systems were designed to have identical annual stocking rates and similar farm areas, pastures and animals. The experiment was conducted for four campaigns (2017-2020) in an upland setting exclusively on permanent grassland under certified-organic farming standards. The young animals were fattened almost exclusively with forages: at pasture for lambs and indoors with haylage in winter for young cattle. Abnormally dry weather conditions led to hay purchases. We compared between-system and between-enterprise performances based on technical, economic (gross product, expenses, margins, income), environmental (greenhouse gas emissions (GHG), energy consumption) and feed-food competition balance indicators. The mixed-species association only benefited the sheep enterprise, with +17.1% meat production per LU (P < 0.03), -17.8% concentrate used per LU (P < 0.02), +10.0% gross margin (P < 0.07) and +47.5% income per LU (P < 0.03) in MIXsys vs SHsys, as well as environmental performance benefits via a reduction of 10.9% in GHG emissions (P < 0.09) and 15.7% in energy consumption (P < 0.03), and a 47.2% improvement in feed-food competition (P < 0.01) in MIXsys vs SHsys. These results are due to both better animal performance and lower concentrate consumption in MIXsys, as presented in a companion paper. These benefits outweighed the additional costs of the mixed system, especially for fencing, in terms of net income per sheep LU. There were no between-system differences in productive and economic performance (kilos live-weight produced, kilos concentrate used and income per LU) for the beef cattle enterprise. Despite good animal performances, the beef cattle enterprises in both CATsys and MIXsys had poor economic performance due to large purchases of conserved forages and difficulty selling the animals, which were ill-adapted to the traditional downstream sector. This multiyear study at the farming-system level, which has thus far been underresearched for mixed livestock farming systems, highlighted and quantified the benefits for sheep when combined with beef cattle on economic, environmental, and feed-food competition performance.
将几种动物物种组合起来以优化整个农业系统的性能是农业生态学的核心原则之一。在这里，我们将绵羊与肉牛（40-60%的牲畜单位（LU））组合在一个混合系统（MIXsys）中，并将其性能与专门的肉牛系统（CATsys）和专门的绵羊系统（SHsys）进行了比较。所有三个系统都设计为具有相同的年度放养率和类似的农场面积、牧场和动物。该实验在一个高地环境中进行了四个阶段（2017-2020 年），完全在认证有机农业标准下的永久性草地进行。年轻动物几乎完全用饲料育肥：羔羊在牧场上，小牛在冬季室内用干草青贮料育肥。异常干燥的天气条件导致需要购买干草。我们根据技术、经济（总产品、支出、利润、收入）、环境（温室气体排放（GHG）、能源消耗）和饲料-食品竞争平衡指标对系统间和企业间的性能进行了比较。混合物种的组合仅对绵羊企业有利，每 LU 的肉产量增加了 17.1%（P<0.03），每 LU 的浓缩饲料使用量减少了 17.8%（P<0.02），毛利润增加了 10.0%（P<0.07），每 LU 的收入增加了 47.5%（P<0.03），与 SHsys 相比，MIXsys 的温室气体排放量减少了 10.9%（P<0.09），能源消耗减少了 15.7%（P<0.03），饲料-食品竞争改善了 47.2%（P<0.01）。这些结果归因于 MIXsys 中动物性能更好和浓缩饲料消耗更低，正如一篇相关论文所介绍的。这些好处超过了混合系统的额外成本，尤其是对于围栏的成本，在每只绵羊 LU 的净收入方面。在肉牛企业的生产和经济性能（活重产量、浓缩饲料使用量和 LU 收入）方面，系统间没有差异。尽管动物表现良好，但由于大量购买青贮饲料和难以销售动物，CATsys 和 MIXsys 中的肉牛企业的经济效益不佳，这些动物不太适应传统的下游部门。这项在农业系统层面进行的多年研究，迄今为止对混合畜牧系统的研究不足，突出并量化了绵羊与肉牛结合在经济、环境和饲料-食品竞争方面的表现所带来的好处。
