A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

Effect of Temperature

Understanding and controlling environmental conditions is crucial to successful poultry production and welfare. Heat stress is one of the most important environmental stressors challenging poultry production worldwide. The detrimental effects of heat stress on broilers and laying hens range from reduced growth and egg production to decreased poultry and egg quality and safety. Moreover, the negative impact of heat stress on poultry welfare has recently attracted increasing public awareness and concern. Much information has been published on the effects of heat stress on productivity and immune response in poultry. However, our knowledge of basic mechanisms associated to the reported effects, as well as related to poultry behavior and welfare under heat stress conditions is in fact scarce. Intervention strategies to deal with heat stress conditions have been the focus of many published studies. Nevertheless, effectiveness of most of the interventions has been variable or inconsistent. This review focuses on the scientific evidence available on the importance and impact of heat stress in poultry production, with emphasis on broilers and laying hens.

https://www.mdpi.com/2076-2615/3/2/356/pdf

Impact of Heat Stress on Poultry Production

Effects of heat stress on animal physiology, metabolism, and meat quality: A review.

Boron is an essential mineral that plays an important role in several biological processes. Boron is required for growth of plants, animals, and humans. There are increasing evidences of this nutrient showing a variety of pleiotropic effects, ranging from anti-inflammatory and antioxidant effects to the modulation of different body systems. In the past few years, the trials showed disease-related polymorphisms of boron in different species, which has drawn attention of scientists to the significance of boron to health. Low boron profile has been related with poor immune function, increased risk of mortality, osteoporosis, and cognitive deterioration. High boron status revealed injury to cell and toxicity in different animals and humans. Some studies have shown some benefits of higher boron status, but findings have been generally mixed, which perhaps accentuates the fact that dietary intake will benefit only if supplemental amount is appropriate. The health benefits of boron are numerous in animals and humans; for instance, it affects the growth at safe intake. Central nervous system shows improvement and immune organs exhibit enhanced immunity with boron supplementation. Hepatic metabolism also shows positive changes in response to dietary boron intake. Furthermore, animals and human fed diets supplemented with boron reveal improved bone density and other benefits including embryonic development, wound healing, and cancer therapy. It has also been reported that boron affects the metabolism of several enzymes and minerals. In the background of these health benefits, low or high boron status is giving cause for concern. Additionally, researches are needed to further elucidate the mechanisms of boron effects, and determine the requirements in different species.

The Physiological Role of Boron on Health.

How can heat stress affect chicken meat quality? - a review

Effects of constant and cyclic heat stress on muscle metabolism and meat quality of broiler breast fillet and thigh meat

Effect of dietary supplementation with protease on growth performance, nutrient digestibility, intestinal morphology, digestive enzymes and gene expression of weaned piglets

Effect of β-hydroxy-β-methylbutyrate calcium on growth, blood parameters, and carcass qualities of broiler chickens

The present study was conducted to investigate the influence of papain (Carica papaya L.) on performance and nutrient digestibility of weaned piglets and to evaluate whether soy protein ingredients supplemented with papain could replace part of high grade animal protein ingredients in weaned piglet feed. The results showed that Km, optimal pH and temperature of papain were 6.6875 mg/mL, 7.0° and 55°C respectively. It had a good stability when either pH ranged from 5.0 to 9.0 or temperature ranged from 4 to 65°C. The addition of papain at 75 mg/kg level significantly increased in vitro crude protein digestibility of soybean meal and piglet feed. Piglets (300; (Pietrain×Duroc)× (Landrace×Yorkshire)) weaned at 21±1 days with an initial body weight (BW) of 5.92±0.47 kg were assigned by BW, sex, and litter according to a randomized complete block design. The animal trial consisted of 5 dietary treatments with 6 replicates/treatment and 0 piglets/replicate. The dietary treatments were positive control (PC), negative control (NC), NC + 50 mg/kg papain, NC + 75 mg/kg papain, and NC +00 mg/kg papain. The results showed that papain significantly decreased diarrhea incidence of piglets fed the diets containing high level of soy-source protein material. There was a linearly improved apparent crude protein digestibility with the increasing dosage of protease. In conclusion, papain supplementation could be considered as an effective solution to break the inclusion limit of soybean source protein ingredients in weaned piglet diet.

Dingyuan Feng

Papers

Effects of constant and cyclic heat stress on muscle metabolism and meat quality of broiler breast fillet and thigh meat

Effect of dietary supplementation with protease on growth performance, nutrient digestibility, intestinal morphology, digestive enzymes and gene expression of weaned piglets

Effect of β-hydroxy-β-methylbutyrate calcium on growth, blood parameters, and carcass qualities of broiler chickens

Preliminary evaluation of papain: its enzymatic characteristics and effects on growth performance and nutrient digestibility in weaned piglets