Effect of Winter Stress on Small Ruminants in North Eastern part of India
The goat population contributes 27.80 percent of the total population livestock in India (536.76 million). During 2023, India produced over 1413.62 tons of goat meat which is 14.47 percent of total meat production in India. India stands as 2nd largest goat meat producing country in the world. Substantial quantity of chevon 17.47 tons is produced in Assam. India ranks first in goat milk production in the world and in 2023 goat milk production in India was 7599.60 tons, which is 3.3 percent of the total milk production of India. However, in Assam only 13.81 tons of milk was produced (BAHS-2023). In Assam, the goat population is approximately 4.32 million and it constitutes 24 percent of the total livestock population in Assam (20th Livestock Census, DAHD, Gol). Goat farming for meat (chevon) production holds significant potential in Assam, where a predominantly non-vegetarian population drives high demand for chevon and its related products. Goats in the region are raised under different systems as reflected according to location, intended use, and economic circumstances. In Assam, goat farming is predominantly practiced by economically weaker farmers and rural women, who often lack the resources for substantial capital investments. Therefore, optimizing housing costs is critical to maximizing profitability in goat farming ventures.
In the Northeast, where high humidity, heavy rainfall, and cold winters prevail, slatted houses with raised floors are ideal as they help maintain a dry, parasite-free environment and provide better protection during winter month. Effective housing management is essential for newborn kids to reduce their mortality during winter season. The comfort and welfare of animal depend significantly on the quality of housing and flooring. The primary purpose of animal shelter is to mitigate climatic stress and create favourable microclimatic conditions, minimizing discomfort and enhancing productivity. Properly ventilated sheds with dry surroundings improve air quality and reduce disease incidence. Cold environments can be especially challenging for young kids, with potential losses of up to 30 percent during severe winter period. New born kids are highly susceptible to cold due to their underdeveloped thermoregulatory system, and thus, a warm, controlled environment is crucial for the initial few days and till weaning age to support their survivability and health. Kid mortality in the pre-weaning period is often attributed to poor growth rates influenced by inadequate housing, insufficient ventilation and winter stress. These factors not only impact growth but also increase susceptibility to diseases and parasitic infestations. Parasitic infestations, are a major concern in goat health management. It adversely affects growth and productivity leading to significant economic losses. Addressing parasitic diseases through improved housing and management practices can, therefore, could enhance productivity. Given that crossbred kids experience higher mortality rates than indigenous breeds due to genetic incompatibility and adaptability issues, ensuring appropriate environmental conditions becomes crucial for optimizing their health and growth.
Environmental conditions, particularly temperature and humidity, significantly influence livestock productivity. During stress periods, animals often spend energy to maintain homeostasis, diverting resources away from growth and production. In Assam, for instance, winters are marked by temperatures dropping below 10°C from November to February. Fog is also common in winter, creating additional environmental stress. The ideal ambient temperature for adult goats is between 15-25°C. Above 80°F (26.6°C) and below 10°C, goats may experience severe heat and cold stress respectively. For optimal health, barn humidity should not exceed 70 percent and airflow at the animal’s level should be below 1.6 feet per second (0.5 meters/second) for adults and 0.65 feet per second (0.2 meters/second) for kids. (Corcy et al.,2002).
The goat population in Assam has declined by about 30 percent since the previous 19th livestock census. Given the widening gap between the demand for goats and chevon in Assam, maintaining a healthy goat population is of utmost essential. Bedding materials like sawdust, straw, or rice husks are essential to keep the floor dry and warm, while protective covering of pen by gunny bags and blankets. In some cases, heat lamps may also be necessary. Hypothermia poses a significant risk to newborn kids, highlighting the importance of proper housing, nutrition, and hydration to mitigate cold stress. Climatic factors directly and indirectly affect livestock. These impacts are observable through the neuroendocrine system’s response to conserve or dissipate heat. Animals respond to environmental stress by modifying their metabolic rates to maintain thermal balance. Physiological responses such as respiration, pulse, and body temperature can provide insights into animals’ adaptability to specific climates. During winter, bedding materials with low thermal conductivity are crucial for conserving body heat, as they enhance lying comfort and prevent productivity losses due to cold stress. Without appropriate bedding, animals may experience discomfort, reduced productivity, and increased susceptibility to diseases and parasitic infestations. Proper bedding is essential to maintain a favourable microclimate within the thermo-neutral zone, thus allowing animals to devote more energy toward growth and productivity.
Winter stress significantly impacts the productivity and welfare of small ruminants, as cold stress affects biological functions, alter antioxidant and hormone levels, and ultimately compromise health, production, and reproduction It is obvious that extremely cold weather conditions have a detrimental impact on the growth performance of goats, particularly affecting younger animals. It is generally recommended that the temperature inside the shelter for kids aged three months or younger remains above 10°C. In climatic regions where temperatures regularly drop below this threshold, additional measures are required to ensure their well-being.
Deepandita Barman1 and Arunoday Das2
Assistant Professor, Department of LPM, LCVSC, Assam Agricultural University
Assistant Professor, Department of ARGO, LCVSC, Assam Agricultural University
