Joint British, Norwegian and Danish studies have shown that the body temperature of newborn piglets one and two hours after birth is strongly related to survival until weaning.
From a stable temperature of between 39 and 40 degrees in the uterus, piglets are born into an environment that is significantly colder and in which they on the whole have to maintain their own body temperature. This transition leads to a drop in body temperature of between 2 and 4 degrees immediately after birth, and there are large differences in how efficiently the piglets recover from this condition. Piglets that do not overcome hypothermia quickly and efficiently die as a direct result of hypothermia, but also from hunger, crushing and disease later in the lactation period.
Therefore, a recently completed PhD project focused on the first few hours immediately following birth. The purpose of the project was to identify characteristics of the piglets that recover successfully from the critical cooling after birth and those that do not. PhD Trine Sund Kammersgaard examined these issues in both loose-housing farrowing pens and conventional farrowing crates.
In addition, the aim was to investigate and document the thermal requirements of newborn piglets in the first three hours after birth and to develop new methods for assessing hypothermia in pigs.
These issues have been examined in three different experiments that were carried out partly in experimental units at AU Foulum and partly in intensive trials in respiratory chambers at Wageningen University in the Netherlands.
In the first study Trine Sund Kammersgaard identified three factors that have a direct impact on the body temperature of the pigs two hours after birth. Ranked in order of priority these are: birth weight, how much time the pigs spend at the udder in the second hour after birth, and how much time the pig spends at the udder in the first hour after birth.
From her studies in the Netherlands she has produced results that suggest that piglet heat requirements in the first few hours are higher than previously thought.
New tools to assess hypothermia in pigs
In practice it is not possible to measure the rectal temperature of all pig. In an experimental context it is important that the measuring methods used are the least intrusive for the animals so as to not affect the results.
Therefore, a focus of Trine Sund Kammersgaard’s PhD project was to develop and test new methods for assessing piglet condition without unnecessary intervention. The methods tested included behavioural observations of lying posture and position, assessment of how much the piglets shiver, and the use of thermographic measurements of body surface temperature. All of these methods appear promising in the assessment of piglet hypothermia.
Source: Aarhus University