Journal ArticleDOI
Models of heat production and critical temperature for growing pigs
J. M. Bruce,J. J. Clark +1 more
TLDR
In this article, a deterministic model for thermoneutral heat production of growing pigs on barley-based diets has been developed and validated, where the model variables are live weight (20 to 100 kg) and metabolizable energy intake (not less than maintenance).Abstract:
1. A deterministic model for thermoneutral heat production of growing pigs on barley-based diets has been developed and validated. The model variables are live weight (20 to 100 kg) and metabolizable energy intake (not less than maintenance). The root-mean-square error for 62 data is 049 MJ/day (3·2%).2. A deterministic model for heat production of growing pigs below their critical temperature has been developed and validated. The model variables are: air temperature, air velocity, floor type, live weight (20 to 100 kg), and group size. The root-mean-square error for 78 data is 0·77 MJ/day (5·6%).3. The two heat production models are combined to give a model for the lower critical temperature for growing pigs.4. These models may be used to quantify and compare the effects on energy balance of different combinations of nutrition and environment. They should help to clarify the issues when practical decisions in pig production are made and should also help in the design of nutritional and physiological experiments.read more
Citations
More filters
Journal ArticleDOI
Applications of computational fluid dynamics (CFD) in the modelling and design of ventilation systems in the agricultural industry: A review
TL;DR: This study provides a state-of-the-art review of CFD, its current applications in the design of ventilation systems for agricultural production systems, and the outstanding challenging issues that confront CFD modellers.
Book
Principles of Environmental Physics: Plants, Animals, and the Atmosphere
TL;DR: The principles of environmental physics: Plants, Animals, and the Atmosphere, 4e as mentioned in this paper provide a basis for understanding the complex physical interactions of plants and animals with their natural environment.
Journal ArticleDOI
Is precision livestock farming an engineer's daydream or nightmare, an animal's friend or foe, and a farmer's panacea or pitfall?
TL;DR: In this paper, the development of precision livestock farming (PLF) from the view point of the engineer, the farm animal and the farmer is reviewed, and it is concluded that PLF is an embryonic technology with great promise but one that requires considerable research and development before uptake.
Journal ArticleDOI
A meta-analysis of the effects of high ambient temperature on growth performance of growing-finishing pigs.
TL;DR: P pig performance decreases at an accelerating rate as T is increased, suggesting that modern genotypes could be more sensitive to heat stress than older genotypes of lesser growth potential.
References
More filters
Book
The energy metabolism of ruminants.
TL;DR: The energy metabolism of ruminants is studied in detail in the context of animal husbandry and its role in human health.
Book
Engineering Thermodynamics: Work and Heat Transfer
TL;DR: In this article, the authors introduce the principles of Thermodynamics and apply them to Particular Fluids, and present the combined modes of Heat Transfer and Combined Modes of Work Transfer.
Journal ArticleDOI
The effects of environmental temperature and plane of nutrition on heat loss, energy retention and deposition of protein and fat in groups of growing pigs
TL;DR: Energy retention depended on both temperature and feeding level, and was highest at the 52 g feeding level at 8°, and N retention was not influenced by environmental temperature but varied with plane of nutrition (correlation coefficient = 0·94); body-weight gain was correlated with N retention rather than with fat deposition.
Journal ArticleDOI
The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig. 1. Heat loss and critical temperature.
W H Close,L E Mount +1 more
TL;DR: The heat losses and energy balances of individually housed pigs were measured continuously for periods of 14 d when they were maintained at environmental temperatures of 10, 15, 20, 25 or 30 degrees and showed that evaporation increased from 25% at 10 degrees to 78% at 30 degrees.