title: Limits to sustained energy intake XXIV: impact of suckling behaviour on the body temperatures of lactating female mice.
abstract: The objective of this study was to investigate the potential causes of high body temperature (Tb) during lactation in mice as a putative limit on energy intake. In particular we explored whether or not offspring contributed to heat retention in mothers while suckling. Tb and physical activity were monitored in 26 female MF1 mice using intraperitoneally implanted transmitters. In addition, maternal behaviour was scored each minute for 8 h d(-1) throughout lactation. Mothers that raised larger litters tended to have higher Tb while nursing inside nests (P < 0.05), suggesting that nursing offspring may have influenced heat retention. However, Tb during nursing was not higher than that recorded during other behaviours. In addition, the highest Tb during the observation period was not measured during nursing behaviour. Finally, there was no indication that mothers discontinued suckling because of a progressive rise in their Tb while suckling. Tb throughout lactation was correlated with daily increases in energy intake. Chronic hyperthermia during lactation was not caused by increased heat retention due to surrounding offspring. Other factors, like metabolic heat produced as a by-product of milk production or energy intake may be more important factors. Heat dissipation limits are probably not a phenomenon restricted to lactation.
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: Y
authors.initials: Y
authors.lastname: Gamo
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: A
authors.initials: A
authors.lastname: Bernard
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: C
authors.initials: C
authors.lastname: Troup
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: F
authors.initials: F
authors.lastname: Munro
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: K
authors.initials: K
authors.lastname: Derrer
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: N
authors.initials: N
authors.lastname: Jeannesson
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: A
authors.initials: A
authors.lastname: Campbell
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: H
authors.initials: H
authors.lastname: Gray
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: J
authors.initials: J
authors.lastname: Miller
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: J
authors.initials: J
authors.lastname: Dixon
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: S E
authors.initials: SE
authors.lastname: Mitchell
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: C
authors.initials: C
authors.lastname: Hambly
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.
authors.forename: L M
authors.initials: LM
authors.lastname: Vaanholt
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, Scotland, UK.|Institute of Genetics and Developmental Biology, State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences, Beichen Xi Lu, Chaoyang, Beijing, People's Republic of China.
authors.forename: J R
authors.initials: JR
authors.lastname: Speakman
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D001522:Behavior, Animal; D001831:Body Temperature / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology*; D005247:Feeding Behavior; D005260:Female; D007774:Lactation / Q000502:physiology*; D008098:Litter Size; D051379:Mice; D013997:Time Factors