title: A radiographic characterization of toe length disparity and its relation to nutrition and structural unsoundness in boars, barrows and sows.
abstract: The front and hind feet from a total of 64 boars, 86 sows and 107 barrows were radiographed after necropsy to study the nature of inequalities in digits and their relation to nutrition and structural unsoundness in swine. Boars were fed ad libitum or 75% ad libitum with 100 or 150% of 1979 NRC recommended vitamin-mineral levels, whereas, sows were fed the same two levels of energy with 100 or 150% of NRC recommended calcium-phosphorus (Ca-P) levels during the growing-finishing period. Barrows were fed two sources of phosphorus with increasing levels of sodium. Radiographs of metacarpals, metatarsals and associated phalanges were measured for length and deviations of proximal and distal extremities. The length of both medial and lateral bones were longer (P less than .05) in boars fed 75% ad libitum than in the ad libitum-fed group, which was probably due to age (285 +/- 8.7 vs 240 +/- 8.4 d). Dietary energy and Ca-P level did not influence the bone lengths in sows. Similarly, dietary phosphorus source or sodium level had no influence on bone lengths or deviations in barrows. The incidence of inequality in digits with a smaller medial digit was 90.9% in boars, 96.7% in sows and 87.6% in barrows. In boars and sows, the inequality in digits of front feet was due to lower positioning of proximal extremities of lateral bones because the total lengths of both medial and lateral bones were approximately equal. In hind feet, this inequality was more due to longer lateral bones because the proximal extremities of metatarsals were positioned at approximately an equal level.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002136:Calcium, Dietary / Q000494:pharmacology; D004734:Energy Metabolism; D005260:Female; D005552:Forelimb; D006614:Hindlimb; D008297:Male; D010710:Phosphates / Q000494:pharmacology; D011859:Radiography; D012965:Sodium Chloride / Q000494:pharmacology; D013552:Swine / Q000033:anatomy & histology* / Q000378:metabolism; D014034:Toes / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000187:drug effects
chemical_list: D002136:Calcium, Dietary; D010710:Phosphates; D012965:Sodium Chloride