title: Marginal dietary zinc concentration affects claw conformation measurements but not histological claw characteristics in weaned pigs.
abstract: The aim of the present study was to explore whether marginal dietary zinc (Zn) concentrations affect claw quality measurements in weaned pigs. Twenty-four weaned pigs were randomly assigned to two dietary treatment groups: (1) 42 mg Zn/kg diet from ingredients only (unsupplemented, marginal dietary Zn concentration below Zn requirements of 80 mg Zn/kg feed); and (2) 106 mg Zn/kg diet, where Zn was added as ZnO (common commercial dietary Zn concentration). Claw conformation characteristics were measured at the start (day 0, 4 weeks of age) and at the end (day 36) of the study, and the histological claw characteristics of horn wall and heel horn were examined on samples collected at 9 weeks of age. Non-supplemented pigs had narrower claw widths (P= 0.028) and lower toe heights (P= 0.010) at 9 weeks. The length of the dorsal border tended to be lower for the non-supplemented piglets (P= 0.092). Claw volume and claw horn size were lower (P= 0.003 and P < 0.001, respectively) for the non-supplemented pigs at 9 weeks of age. Horn growth and wear were lower for the non-supplemented pigs (P= 0.044 and P < 0.001, respectively), but net horn growth (horn growth minus wear) was not different (P= 0.406). No changes in the histological claw characteristics were observed. Differences in claw quality measurements were found between lateral and medial claw digits and between fore and hind claws. It was concluded that marginal dietary Zn concentration affected various claw quality measurements. Marginal dietary Zn concentrations may not be sufficient to maintain claw quality in pigs.
authors: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium; Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Miriam M J
authors: MM
authors: van Riet
authors: Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Geert P J
authors: GP
authors: Janssens
authors: Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Pieter
authors: P
authors: Cornillie
authors: Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Wim
authors: W
authors: Van Den Broeck
authors: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium; Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Elena
authors: E
authors: Nalon
authors: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium.
authors: Bart
authors: B
authors: Ampe
authors: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium; Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Frank A M
authors: FA
authors: Tuyttens
authors: Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Dominiek
authors: D
authors: Maes
authors: Faculty of Bioscience Engineering, Laboratory of Analytical Chemistry and Applied Ecochemistry, Ghent University, Ghent, Belgium.
authors: Gijs
authors: G
authors: Du Laing
authors: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium. Electronic address: sam.millet@ilvo.vlaanderen.be.
authors: Sam
authors: S
authors: Millet
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis; D005260:Female; D006724:Hoof and Claw / Q000033:anatomy & histology / Q000502:physiology*; D008297:Male; D011897:Random Allocation; D034421:Sus scrofa / Q000033:anatomy & histology / Q000502:physiology*; D014886:Weaning; D015032:Zinc / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D015032:Zinc
keywords: Claw dimensions; Histology; Horn growth; Pigs; Zinc oxide