Seasonal Variation in Rectal Temperature of Holstein Friesian Cattle in The Guinea Savanah Zone of Nigeria (original) (raw)
Related papers
Heat Stress in Dairy Cows-Its Impact and Management: A Short Notes
2018
An imbalance between metabolic heat production inside the animal body and its dissipation to the surroundings results to heat stress (HS) under high air temperature and humid climates. Heat stress has several serious and economically deleterious effects on cattle. The most important effects of heat stress in dairy cows are increased body temperature, reduced feed intake, milk production, increased somatic cell count and lower reproductive performance. The provision of cooling shed and dietary manipulation is the most important management tool to reduce heat load in dairy cows.
SOJ Veterinary Sciences, 2015
SOJ Veterinary Sciences Open Access Review Article ways by which animals can get rid of their thermal body load: conduction, convection, radiation (Figure 1). In the zone I-III the animal can maintain a constant body temperature; in zone I-II and zone II-III heat production and heat loss is regulated. In zone I-II, heat production increases in order to maintain homeostasis. Zone II-III is the thermo-neutral zone, where heat loss is kept constant. Factors other than climate (e.g. ration, milk yield level, activity) determine the heat production in that zone [2]. The temperature points II and III are the lower and upper critical temperatures respectively, beyond which cold stress and heat stress respectively occur. When temperature increases beyond a given critical limit, the non-evaporative ways of heat loss appear to be far less efficient. And if temperature rises even more, the cow changes from a non-evaporative to an evaporative way. However, the latter is strongly dependant on the level of air humidity. The thermo-neutral zone of dairy cows in full lactation is, roughly speaking, between-5°C and +20°C for adult dairy cows
Assessment of heat stress in dairy cows related to physiological responses
Jurnal Ilmu-Ilmu Peternakan
Climate change will continue to occur in the years to come and threaten dairy cows. As a result of climate change, various risks can change due to changing ecological conditions in various places on earth. The study aimed to assess heat stress in dairy cows (calf, heifer, lactating, and dry cow). The heat stress assessment method uses the equation presented by the temperature-humidity index (THI). Heart rate, respiratory rate, and rectal temperature are physiological parameters to determine heat stress. The data collection of cattle's temperature, humidity, and physiological parameters was carried out simultaneously. Data analysis used one-way ANOVA, followed by Tukey's further test. The results of the heat stress assessment showed that the THI values reached 82.8 and 78.2 in the afternoon and evening, causing the calves, lactating cow, and dry cow to be exposed to heat stress. The rectal temperature of the calf increased by 39.10C, the heart rate and respiration rate of lac...
THERMAL STRESS IN DAIRY CATTLE 12 3 4
Crosses of temperate cattle reared in tropical ambience lapse in heat tolerance, fertility and disease resistance. However, cross breeding zebu with high yielding exotic cattle seems necessary to meet the need for enhanced composite milk production per unit in view of food security. Thermal stress is considered as the main factor responsible for reduction of milk yield in tropical climate. Any model for the study of thermal stress in dairy cattle should encompass related effect of ambient parameters of temperature, humidity, wind speed and solar radiation as the stressor and behavioural, autonomic, neuroendocrine and immunological endpoints as responses. The responses reach different response states depending on the severity of the stressor. Response measurements are at behavioural, physiological, biochemical and cellular level, which also include hormone, protein and gene expression assays. By fitting these measurements to the described model we can work out the biological and economic cost of thermal stress and the level of adaptation of the dairy animal in question. Such studies taking in to consideration the diverse nature of climatic factors is imperative for finding ameliorative measures to reduce the thermal stress experienced by the existing cattle population and for the possible genetic and management strategies for evolving and maintaining a climatically adapted dairy stock in a state like Kerala. This review analyses suitable model for climatic adaptation studies in the hot and humid climate especially in small holder production systems.
Effect of Environmental Heat Stress on Reproduction Performance of Dairy Cows- A Review
International Journal of Livestock Research, 2015
Stress is the condition where there is undue demand for physical and mental energy due to excessive and aversive environmental factors (stressors) and cause deformations those are identifiable through physiological disequilibrium. Temperature stress imparts physical and economical losses to livestock production in temperate, subtropical and tropical regions of the world. Each species, breed or animal with its physiological state, has a comfort zone, in which the energy expenditure of the animal is minimal, constant and independent of environmental temperature. When environmental temperatures move out of the thermo-neutral zone (or comfort zone) dairy cattle begin to experience heat stress. Thermo-neutral zone depends on the age, breed, feed intake, diet composition, previous state of temperature acclimatization, production, housing and stall conditions, tissue (fat, skin) insulation and external (coat) insulation, and the behaviour of the animal. The ranges of thermo-neutral zone are from lower critical temperature (LCT) to upper critical temperature (UCT). LCT is the environmental temperature at which an animal needs to increase metabolic heat production to maintain body temperature. UCT is the environmental temperature at which the animal increases heat production as a consequence of a rise in body temperature resulting for inadequate evaporative heat loss. Heat stress negatively impacts a variety of dairy parameters including milk yield and reproduction and therefore is a significant financial burden in many dairy-producing areas of the world. Advances in management (i.e. cooling systems) and nutritional strategies have alleviated some of the negative impact of thermal stress on dairy cattle, but production continues to decrease during the summer. In this review an attempt has been made to bring forth the effect of heat stress and to discuss their impact on dairy cows.
Physiological and pyhsical responses of dairy cattle to heat stress
Black sea journal of agriculture, 2022
Herd management and nutrition strategies against increasing negative effects of global warming on farm animals have been the subject of significant debates in recent years. The fact that the changes in the environmental conditions are directly related to the habitats of the animals and the conditions inside the barn can affect the farm animals negatively. Although effects of heat stress differ according to species, especially high-yielding dairy cattle exposed to heat stress, respond with various interactive mechanism such as physiological, biochemical, immunological, anatomical and behavioral. Therefore, with the selection practices that have been going on for many years to improve the yield characteristics of the animals significantly increased. In this respect, the increased heat load in the body of dairy cattle due to the high productivity decreases their tolerance to environmental conditions. This situation adversely affects the productivity of cows with high breeding value. Yield losses, varying according to some factors about heat stress, can be partially explained by decreasing feed intake as a result of a series of hormonal responses affecting appetite center. However, the physiological requirements of cattle must be defined in order to develop appropriate strategies to reduce or eliminate the negative effects of heat stress. In this review, the variations in physiological, biochemical and behavioral mechanisms originating from heat stress in dairy cattle and the care, nutrition and herd management strategies that can be applied to eliminate or reduce the negative effects were discussed.
Impact of heat stress on health and performance of dairy animals: A review
Sustainability in livestock production system is largely affected by climate change. An imbalance between metabolic heat production inside the animal body and its dissipation to the surroundings results to heat stress (HS) under high air temperature and humid climates. The foremost reaction of animals under thermal weather is increases in respiration rate, rectal temperature and heart rate. It directly affect feed intake thereby, reduces growth rate, milk yield, reproductive performance, and even death in extreme cases. Dairy breeds are typically more sensitive to HS than meat breeds, and higher producing animals are, furthermore, susceptible since they generates more metabolic heat. HS suppresses the immune and endocrine system thereby enhances susceptibility of an animal to various diseases. Hence, sustainable dairy farming remains a vast challenge in these changing climatic conditions globally.
Effects of Heat-Stress on Production in Dairy Cattle
Journal of Dairy Science, 2003
The southeastern United States is characterized as humid subtropical and is subject to extended periods of high ambient temperature and relative humidity. Because the primary nonevaporative means of cooling for the cow (radiation, conduction, convection) become less effective with rising ambient temperature, the cow becomes increasingly reliant upon evaporative cooling in the form of sweating and panting. High relative humidity compromises evaporative cooling, so that under hot, humid conditions common to the Southeast in summer the dairy cow cannot dissipate sufficient body heat to prevent a rise in body temperature. Increasing air temperature, temperature-humidity index and rising rectal temperature above critical thresholds are related to decreased dry matter intake (DMI) and milk yield and to reduced efficiency of milk yield. Modifications including shade, barns which enhance passive ventilation, and the addition of fans and sprinklers increase body heat loss, lowering body temperature and improving DMI. New technologies including tunnel ventilation are being investigated to determine if they offer cooling advantages. Genetic selection for heat tolerance may be possible, but continued selection for greater performance in the absence of consideration for heat tolerance will result in greater susceptibility to heat stress. The nutritional needs of the cow change during heat stress, and ration reformulation to account for decreased DMI, the need to increase nutrient density, changing nutrient requirements, avoiding nutrient excesses and maintenance of normal rumen function is necessary. Maintaining cow performance in hot, humid climatic conditions in the future will likely require improved cooling capability, continued advances in nutritional formulation, and the need for genetic advancement which includes selection for heat tolerance or the identification of genetic traits which enhance heat tolerance.
Effect of heat stress during early, late, and entire dry period on dairy cattle
Journal of Dairy Science, 2019
Cooling during the entire dry period abates the negative effects of heat stress postpartum, yet the temporal relationship of cooling (i.e., early or late dry period) to performance is unknown. We evaluated the effect of heat stress early, late, and for the entire dry period on subsequent performance. Cows were selected based on mature-equivalent milk yield and dried off 45 d before expected calving. Cows were blocked by parity, previous 305-d mature equivalent milk yield, and body weight (BW) and randomly assigned to cooling (shade, fans, and soakers; CL) or heat stress (shade; HT). Treatments included CL (n = 20) or HT (n = 18) during the entire dry period, HT during the first 3 wk dry and then CL until calving (HTCL, n = 21), or CL during the first 3 wk dry period and then HT until calving (CLHT, n = 19). Heat stress increased rectal temperature (RT; CL, 38.8; HT, 39.1 ± 0.04°C) and respiration rate (RR; CL, 52.9; HT, 70.5 ± 1.9 breaths/min) during the early dry period. In the late dry period, HT increased RT and RR relative to CL cows (
® and the Effect on Heat Stress in Dairy Cows
2014
One of the great challenges that the dairy industry faces, especially during the summer month, is heat stress. Increase in temperature, together with an increase in humidity, results in a decrease in milk production, feed intake, feed efficiency and even reduced growth rate in heifers (West, 1999). Reproduction and health are also negatively affected by heat stress (St Pierre et al., 2003). Different management systems are used to reduce the effect of heat stress on dairy cows, for example, fans with water sprayers or dairy cow housing (shading). However, not all dairies are able to implement these kind of management systems, and even with these, cows still experience a certain amount of heat stress, depending on the environment.