title: Lambs prevented from suckling their mothers display behavioral, immune and endocrine disturbances.
abstract: The aim of the experiment was to assess the effects of either maternal deprivation or prevented suckling on lambs. Thirty Comisana lambs were assigned to a control dam-suckled group (DS) and two test groups of 10 each. Test lambs were maintained with their mothers 24 to 30 h after parturition and subsequently offered ewe milk from buckets: EM lambs were separated from their mothers, while EM+D animals were reared with their dams but suckling was denied by covering ewe udders with juta bags. Behavioral, immune and cortisol responses of lambs were assessed throughout the experiment. EM+D lambs spent less time (P<.001) on investigative behavior compared to the two other groups. When isolated in a novel environment, EM+D lambs exhibited a shorter duration of movement (P<.01) and a longer latency time compared to DS and EM lambs (P<.001 and P<.05, respectively) as well as a higher number of bleats (P<.01) than EM lambs. EM+D lambs also displayed higher (P<.001) plasma cortisol levels than the other two groups when isolated at 4 days of age. When subjected to discrimination tests, EM+D lambs spent less time near their companions (P<.01) than EM lambs and took a longer time to reach their pen mates (P<.01) than DS and EM lambs. EM+D lambs displayed reduced growth (P<.001) compared to DS animals during the 0-7 and 8-14-day periods. We conclude that frustration arising from maternal feeding deprivation results in altered endocrine and behavioral responses and reduced growth suggesting emotional disturbances of lambs.
authors.affiliation: Dipartimento di Scienze delle Produzioni Animali, via Nazario Sauro, 85100 Potenza, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Napolitano
authors.forename: Giovanni
authors.initials: G
authors.lastname: Annicchiarico
authors.forename: Mariangela
authors.initials: M
authors.lastname: Caroprese
authors.forename: Giuseppe
authors.initials: G
authors.lastname: De Rosa
authors.forename: Luigi
authors.initials: L
authors.lastname: Taibi
authors.forename: Agostino
authors.initials: A
authors.lastname: Sevi
mesh_terms: D000818:Animals; D000833:Animals, Suckling / Q000276:immunology / Q000523:psychology*; D001522:Behavior, Animal / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D004703:Endocrine System / Q000502:physiology*; D006854:Hydrocortisone / Q000097:blood; D007109:Immunity / Q000502:physiology*; D007958:Leukocyte Count; D008297:Male; D008426:Maternal Deprivation; D008892:Milk / Q000737:chemistry; D010047:Ovalbumin / Q000276:immunology; D010835:Phytohemagglutinins / Q000276:immunology; D012756:Sheep; D012919:Social Behavior; D012934:Social Isolation / Q000523:psychology; D014886:Weaning; D015430:Weight Gain / Q000502:physiology
chemical_list: D010835:Phytohemagglutinins; D010047:Ovalbumin; D006854:Hydrocortisone