Restricted Energy Intake and Elevated Calcium and Phosphorus Intake for Boars during Growth. II. Foot and Leg Measurements and Toe and Soundness Scores

Abstract

Boars were assigned at 5 wk of age in a 2 X 2 factorial arrangement to two energy (ad libitum and 75% of ad libitum) and two Ca and P levels (100 and 150% of the National Research Council daily recommended amounts) to determine the effect of reduced growth rate and elevated Ca and P intake on foot and leg measurements, pad and horn incidence and severity of lesions, and structural soundness. There were 20 boars/treatment; 15 boars from each treatment were necropsied at 10 +/- 2-d intervals from 80 to 220 d of age (45 to 185 d on test), with the remaining five boars in each treatment being necropsied at 220 d of age. Feet and leg measurements were taken and toe pads and horns were scored initially and after 78 and 131 d on when necropsied. Boars remaining after 130 d on test were scored for overall structural soundness. Toe size and circumference and length of limbs increased as boars grew, with larger values for ad libitum-fed compared with limit-fed boars when observed at a constant age. However, when these values were corrected for body weight, the effect of energy was generally removed and, in some cases, reversed. Limit-fed boars appeared to have fewer pad and horn lesions, but the effects were inconsistent. In general, Ca and P levels had little or no effect on toe and limb sizes and pad and horn lesion scores, whether or not the values were expressed on a constant age or corrected body weight basis. A comparison of inside and outside toes on the front and hind feet revealed that outside toes were larger than inside toes, with the magnitude of the difference much larger for the hind foot than for the front foot. The hind inside toes had fewer pad and horn lesions. Structural soundness scores were more desirable in ad libitum-fed compared with limit-fed boars; but, elevated Ca and P levels had no effect. Thus, these data do not support a hypothesis that structural soundness can be improved by reducing the growth rate of developing boars or by feeding an elevated level of Ca and P.

Foot and Leg Measurements, Toe Lesions, Soundness Scores and Feedlot Performance of Crossbred Boars as Influenced by Nutrition and Age

“…In agreement, Vaughan (1971) suggested that rapid growth may predispose an animal to leg weakness problems. In contrast, Kornegay et al (1983) reported that ad libitum-fed boars showed increased soundness score when the scores were cor- The present study supports the results of Nimmo et al (1980a,b), Kornegay et al (1981Kornegay et al ( , 1983 and Calabotta et al (1982) (Calabotta 1979;Bryant 1982) and with sows (Bryant 1982;Arthur et al 1983) (Braude and Townsend 1958;Frape et al 1959;Nielsen 1964;'Calabotta et al 1982;Kesel et al 1983). …”

“…In contrast, several other researchers have reported no beneficial effect of energy restriction (Fell et al l97O;Nakano et al 1979;Calabotta etal. 1982;Kornegay et al 1983;Arthur et al 1983). Likewise, feeding Ca and P levels in excess of National Academy of Sciences-National Research Council (NAS-NRC 1979) recommendations have not improved structural soundness scores in gilts (Calabotta et al 1982) and boars (Nimmo et al l980a,b;Kornegay et al 1981Kornegay et al , 1983).…”

“…The present study was undertaken to elucidate further the effects ofreduced growth rate and elevated dietary mineral and vitamin levels (l50Vo NAS-NRC (1979) Kornegay et al (1983) at 87 days on test, with the difference significant at 255 days on test (Table 6). However, the improvement was small.…”

Metacarpal and Metatarsal Dimensional, Mechanical and Mineral Characteristics of Crossbred Boars as Influenced by Nutrition and Age

“…In another paper in this series, Lepine et al (1985) found that elevating mineral and vitamin intake above that recommended by NAS-NRC (1979) had no effect on toe, foot and leg development and resulting structural soundness, which agrees with previous reports (Grondalen 1976;Reiland 1978;Nimmo et al 1980b;Kornegay and Thomas 1981;Kornegay et al 1981Kornegay et al , 1983Calabotta etal. 1982;Arther et al 1983a …”

Porcine somatotropin effects on performance, carcass and leg soundness traits of normal, carrier and stress susceptible swine

“…Some authors suggested that pigs excelling in growth rate encounter a greater degree of leg weakness problems than slower growing counterparts (Grondalen, 1974;Lundeheim, 1987). In contrast, other studies reported reduced leg weakness with faster growth (Reiland et al, 1978;Kornegay et al, 1983) or no apparent relationship between the two traits (Kornegay et al, 1981;Webb et al, 1983;Rothschild et al, 1988). Correspondingly, increased incidence of osteochondrosis was associated with rapid growth rate in an earlier study of Goedegebuure et al (1980).…”