A case of suckling and allosuckling behaviour in captive common hippopotamus

摘要: Lactation is a form of maternal investment that far moredemanding than gestation, oestrus behaviour or ovulation (Martin,1984; Oftedal, 1985). However although suckling hasbeenstudiedinmanyungulatespeciesindetail(CarsonandWood-Gush, 1983; Lavigueur and Barrette, 1992; Sarno Franklin,1999), there have been few studies on ofcommon hippopotamus (Hippopotamus amphibius). The sucklingbouts take place both land (Bartlett, 1872; Sokolowsky, 1915;Verheyen, 1954; Eltringham, 1999) in the water (Vosseler,1923; Vevers, 1926; Verheyen, 1954) last around 3–4.5min(Vosseler,1923)withthemotherusuallylyingonherside(Bartlett,1872; 1999). Suckling was suggestedto occur mostly morning (Olivier Laurie, 1974). No otherdetails including exact length bouts, which animalinitiated (foal mother) terminated bout, numberand interruptions were published (for review see:Estes, 1991; Thus, basic biological informa-tion concerning common hippopotamusis still lacking. Since observation hippopotami wildis difficult, observations carried out zoos would improve ourknowledge this (Verheyen, 1954).Allosucklinghasbeenreportedinmostmammaliantaxa(Packeret al., Roulin, 2002). In hippos, occurrence ofallosuckling suggested but not proven (Smuts Whyte,1981). allosuckling monotocous species has