Normal profiles for deciduous dental eruption in domestic piglets: Effect of sow, litter, and piglet characteristics

Abstract

The deciduous dentition of the domestic pig is comprised of 28 teeth (2 × incisors 3/3, canine 1/1, premolars 3/3, molars 0/0). The timing and sequence of deciduous dental eruption were determined from oral exams on 233 Yorkshire piglets from 0 to 5 wk of age. Eruption occurred sooner in gilts for all molariform premolars (p3, p4, and p4, P < 0.01) and first incisor, i1 (P = 0.004). Birth weight influenced eruption for all teeth except i1 (i1, p3, p3, p4, and p4; P < 0.01), with heavier piglets having earlier eruption. Average daily gain in wk 1 of life was associated with earlier eruption times of p3 (P = 0.006), p4 (P = 0.001), and i1 (P = 0.001), whereas ADG during wk 2 was associated with earlier eruption for p4 (P = 0.036). The parity (P = 0.025) and age (P = 0.013) of the sow were associated with earlier eruption of i1. No litter characteristics were found to be significant. Sequence of eruption was determined to be i1, p3, p4, i1, p3, p4, although polymorphisms (reversals) were found to occur in over 40% of individuals of both sexes for mandibular i1 and p4 and maxillary p3 and i1. Size of the left i3, which is already erupted at birth as part of the needle teeth dentition, was found to be larger in males (P = 0.026). Body weight gain was not associated with the size of i3. Eruption times of p3 and p4 (the first premolars to erupt) occurred later than previously reported in the literature. Because these teeth are associated with initiation of feeding behavior for miniature breeds, implications of molar eruption on feeding behavior and feed intake should be considered. © 2009 American Society of Animal Science.