Breeding for efficient production of eggs and poultry meat

Abstract

ForewordDespite careful pasture management, parasites can become a real threat to profitable sheep production. Thus, even the best grazier must at times resort to some drug to relieve his flock of parasites. Reliance upon such drugs must be even greater at lower levels of management or under adverse conditions which disrupt even the soundest management.Anthelmintic drugs thus have become a necessity for profitable sheep production, particularly in the humid grazing areas. A steady improvement in anthelmintic efficacy has been experienced with the addition of each new drug to the shepherd's shelf. To the long-used copper-sulfate and nicotine sulfate combination was added phenothiazine. Now, one of the most recent additions, thiabendazole, promises to make the sheepman's arsenal against parasites more effective than ever.The work described in this bulletin represents the cooperative efforts of several people. The initial trials conducted in the 1960 grazing season were largely the work of Dr.

Crossbreeding and Upgrading of the Indigenous Fowl of Nigeria with Improved Breeds

“…This is presented in Table 3 and was represented in the liveweight of all the crossbreds, although the crossbreds were themselves lighter than the heavier parent. The amount of heterosis in this study is comparable in magnitude with estimates previously reported (MERRIT and GOWE, 1960;HYNE et al, 1962 andJAAP, 1968 Fig. 1 shows heterosis in absolute weight, increasing slightly in magnitude with the age of the fowl in the RIR x Ind.…”

“…Upgrading entails crossbreeding which initially may produce heterosis in the F,. Heterosis in body weight at different ages during growth has been reported in several studies (MERRIT and GOWE, 1960;HYNE et al, 1962;JAAP, 1968;TOMOVA, 1968). Heterosis might occur in one reciprocal and not the other of an F, crossbred as found by HYNE et al (1962), ZIEBA (1965), BUVANENDRAN (1967) and TOMOVA (1968).…”

“…Heterosis in body weight at different ages during growth has been reported in several studies (MERRIT and GOWE, 1960;HYNE et al, 1962;JAAP, 1968;TOMOVA, 1968). Heterosis might occur in one reciprocal and not the other of an F, crossbred as found by HYNE et al (1962), ZIEBA (1965), BUVANENDRAN (1967) and TOMOVA (1968). In fact, heterosis may not exist in body weight of crossbred chicks (MORRIS andSKAL-LER, 1958 andHYNE et al, 1962).…”

“…Heterosis might occur in one reciprocal and not the other of an F, crossbred as found by HYNE et al (1962), ZIEBA (1965), BUVANENDRAN (1967) and TOMOVA (1968). In fact, heterosis may not exist in body weight of crossbred chicks (MORRIS andSKAL-LER, 1958 andHYNE et al, 1962).…”