Colditz Ian G
CSIRO Agriculture and Food, Armidale 2350, Australia.
Animals (Basel). 2018 Apr 3;8(4):50. doi: 10.3390/ani8040050.
Genetic selection of farm animals for productivity, and intensification of farming practices have yielded substantial improvements in efficiency; however, the capacity of animals to cope with environmental challenges has diminished. Understanding how the animal and environment interact is central to efforts to improve the health, fitness, and welfare of animals through breeding and management strategies. The review examines aspects of the environment that are sensed by the animal. The predictive brain model of sensory perception and motor action (the Bayesian brain model) and its recent extension to account for anticipatory, predictive control of physiological activities is described. Afferent sensory input from the immune system, and induction of predictive immune functions by the efferent nervous system are also in accord with the Bayesian brain model. In this model, expected sensory input (from external, physiological and immunological environments) is reconciled with actual sensory input through behavioural, physiological and immune actions, and through updating future expectations. Sustained discrepancy between expected and actual sensory inputs occurs when environmental encounters cannot be predicted and controlled resulting in stress and negative affective states. Through these processes, from the animal's perspective, aspects of the environment acquire a negative or positive character: that is the environment becomes valenced. In a homeostatic manner, affective experience guides the animal towards synchronisation and a greater degree of mutualism with its environment. A better understanding of the dynamic among environmental valence, animal affect and mutualism may provide a better understanding of genetic and phenotypic links between temperament, immune function, metabolic performance, affective state, and resilience in farm animals, and provide further opportunities to improve their welfare.
对农场动物进行生产力方面的基因选择以及强化养殖方式已在效率上取得了显著提升;然而,动物应对环境挑战的能力却有所下降。了解动物与环境如何相互作用是通过育种和管理策略来改善动物健康、体能和福利的核心所在。本综述探讨了动物所感知到的环境方面。描述了感官知觉和运动行为的预测性大脑模型(贝叶斯大脑模型)及其最近为解释生理活动的预期性、预测性控制所做的扩展。来自免疫系统的传入感觉输入以及传出神经系统对预测性免疫功能的诱导也符合贝叶斯大脑模型。在这个模型中,预期的感觉输入(来自外部、生理和免疫环境)通过行为、生理和免疫行动,并通过更新未来预期,与实际的感觉输入相协调。当无法预测和控制与环境的接触时,预期和实际感觉输入之间就会持续出现差异,从而导致压力和负面情绪状态。通过这些过程,从动物的角度来看,环境的各个方面会呈现出负面或正面的特征:也就是说环境具有了效价。以一种稳态的方式,情感体验引导动物与环境实现同步并达到更高程度的共生关系。更好地理解环境效价、动物情感和共生关系之间的动态变化,可能会让人更好地理解农场动物的气质、免疫功能、代谢性能、情感状态和恢复力之间的基因和表型联系,并为改善它们的福利提供更多机会。