Broiler chickens in Brazil are generally reared from 1 to 42 days when they are exposed to procedures such as fasting, harvesting, crating and transport to slaughter. Maintaining homeostasis is of great importance for broiler survival under harsh environment especially prior to slaughter. Heat loss varies in the distinct parts of the body during the growth period, and it is related to the air temperature of the environment and to the amount of feather covering. This research aimed to study the surface temperature distribution using infrared thermographic image processing to characterize 42 day old broiler chicken surface temperature prior to slaughter. Broilers were reared for 42 days and prior to harvest and transport to slaughter the infrared surface temperature was recorded along the day. Data from the thermograms taken in feather and featherless regions were compared during the 42nd day of growth. High correlation between featherless regions and air temperature was found showing that these areas respond fast to changes in the rearing environment. Two functions were developed for predicting both surface temperature for featherless and feather covered areas of the broiler body parts.

Infrared thermal imaging is a non-destructive testing technology that can be used to determine the superficial temperature of objects. This technology has an increasing use in detecting diseases and distress in animal husbandry within the poultry, pig and dairy production. The process can identify changes in peripheral blood flow from the resulting changes in heat loss and; therefore, have been a useful tool for evaluating the presence of disease, edema, and stress in animals. This paper reviews the current literature related to the use of infrared technology and discusses their results and implications in animal welfare issues, poultry, pig and bovine industry.

Various degrees of lameness were compared among male broilers ranging in age from 28 to 49 d that had been randomly selected from a commercial farm.

The study was carried out in order to verify the effects of piglets' weight at birth on their surface temperature change (ST) after birth, and its relationship with ingestion time of colostrum. Piglets from four different sows were weighed at birth and divided into a totally randomized design with three treatments according to birth weight (PBW): T1 - less than 1.00 kg, T2 - 1.00 to 1.39 kg, and T3 - higher than or equal to 1.40 kg. The time spent for the first colostrum ingestion was recorded (TFS). Images of piglets' surface by thermal imaging camera were recorded at birth (STB) and 15, 30, 45, 60, and 120 min after birth. The air temperature and relative humidity were recorded every 30 min and the indexes of temperature and humidity (THI) were calculated. A ST drop after 15 min from birth was observed, increasing again after sixty minutes. Positive correlations were found between the PBW and the ST at 30 and 45 min after birth. The PBW was negatively correlated with the TFS. The THI showed high negative correlations (-0.824 and -0.815) with STB and after 15 min from birth. The piglet's surface temperature at birth was positively correlated with temperature thereof to 15 min, influencing therefore the temperatures in the interval of 45 to 120 min. The birth weight contributes significantly to postnatal hypothermia and consequently to the time it takes for piglets ingest colostrum, requiring special attention to those of low birth weight.

Broiler building typology associated with the local characteristics (climate, topography and surrounding vegetation) and handling systems (stocking density, curtains, equipment and nutrition) influence the inside environment. A spatial distribution analysis of these conditions may indicate stress zones in the house. The aim of this research was to apply spatial analysis of thermal, aerial and acoustic environmental conditions inside a tunnel ventilated broiler housing, with a stocking density of 18 birds m-2. This study was carried out in Rio Claro, SP, Brazil, in a 12 m × 115 m house divided into three equal sections (East, center and West), East-West oriented, and virtually divided on 132 cells, each one measuring 3.0 m × 3.5 m. At the geometric center of each cell the following variables were monitored: dry bulb temperature, relative humidity, air velocity, noise level and light intensity. Average broiler mortality was recorded in each of the three sections. Data collection was made systematically from West to East, opposite to the air flow produced by the tunnel ventilation system, during the warmest period of the day. Measurements took place during the sixth week of production. A geostatistics software tool was used to build spatial distribution maps of the recorded variables in order to infer intermediate stress conditions. It was concluded that the stress zones were located at both ends of the house and the highest mortality index was found at the West sector where the exhaust fans were placed.