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An experiment with 127 barrows representing five genotypes, 1) H x HD, 2) SYN, 3) HD x L[YD], 4) L x YD, and 5) Y x L (H = Hampshire, D = Duroc, SYN = synthetic terminal sire line, L = Landrace, and Y = Yorkshire), was conducted to evaluate growth and development of swine from 59 to 127 kg live weight. Animals were allowed ad libitum access to a pelleted finishing diet containing 18.5% CP, .95% lysine, and 10.5% fat, with an energy density of 3,594 kcal of ME/kg. Pigs were serially slaughtered at either 59, 100, 114, or 127 kg live BW. After slaughter, carcasses were chilled and backfat was measured at four locations. The right side of each carcass was fabricated into primal cuts of ham, loin, Boston Butt, picnic, and belly. Composition of each primal cut was determined by physical dissection into lean, fat, bone, and skin. Estimated allometric growth coefficients for carcass length, carcass weight, and longissimus muscle area relative to BW; carcass lean, fat, bone, and skin relative to both BW and carcass weight; and lean in each of the primal cuts relative to total carcass lean did not differ (P greater than .05) among genotypes. Relative to BW, the pooled growth coefficient(s) for carcass weight was (were) greater (P less than .001) than unity, whereas those for carcass length, longissimus muscle area, and backfat at first rib were smaller (P less than .001) than unity. Those for other backfat measurements were close to 1.00. Relative to either BW or carcass weight, the pooled coefficient(s) for fat was (were) greater (P less than .001) than unity, whereas those for lean, bone, and skin were smaller (P less than .001) than unity. Growth of lean, backfat, bone, and skin in the carcass were nearly linearly associated with increases in BW. The increase in fat weight was curvilinear as the pig grew and was accelerated in later growth stages, indicating that carcass fat percentage increased with increased BW.

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In this study the predation and ®sh prey selection of otters Lutra lutra L. living by eutrophic ®sh ponds on agricultural land and in a protected area of temperate climate in Hungary were investigated. The correlations between ®sh in the diet of the otters (by spraint analysis involved 1942 and 1280 samples for the two habitats) and the ®sh stock available (by harvest and sample ®shing) were generally close. Prey selection was signi®cantly related to selected species of a particular size range (P < 0.01). The preference calculations were performed with Ivlev's index of preference (E i , minimum 71, maximum +1). Regardless of species, the otters avoided (E i = 70.51) ®sh heavier than 1000 g, with a preference for individuals weighing between 500 and 1000 g (E i = 0.79). No substantial or clear preference was observed in the weight range below 500 g (E i = 70.02±0.38). The preference for ®sh in accordance with their characteristic sites of occurrence within the body of water was also signi®cant (P < 0.01). They avoided ®sh living primarily in open water (E i = 70.64) and to a lesser degree those occurring near the pond bed (E i = 70.22). They favoured ®sh inhabiting the area with a covering of aquatic plants (E i = 0.46), and showed a preference to a lesser degree for ®sh living in the shallow littoral regions (E i = 0.14). With the cessation of ®sh farming and the effect of the drastic changes which occurred in the vegetation, the otters fed substantially on the stock of alternative sources of prey such as amphibians and water insects as well as terrestrial animals, and at such times, depending on season, ®sh became a secondary source of prey.