{"title":"初产年龄与雏鸡首蛋大小相关性的初步研究。*","authors":"Lippincott William A.","doi":"10.3382/ps.0070073","DOIUrl":null,"url":null,"abstract":"<div><p>Early maturity has been a cardinal point of selection since the time of Robert Bakewell, with whom systematic breeding of meat producing animals began. That, on a given ration, the quickest gains are the cheapest gains, is axiomatic among livestock breeders generally. That it holds for growth gains in chickens as for the larger farm animals there is little reason to doubt though a cursory search of the literature has failed to show exact and satisfactory data bearing on this point.</p><p>Rice (1915) has shown that there is an important relationship existing between earliness of maturity in White Leghorn pullets as indicated by their age at the laying of their first egg, and the rate and persistence of egg production. This relationship is of such a nature as to indicate that the earlier the age at which a Leghorn pullet begins to lay, the greater is the number of eggs . . .</p></div>","PeriodicalId":100836,"journal":{"name":"Journal of the American Association of Instructors and Investigators of Poultry Husbandry","volume":"7 10","pages":"Pages 73-74"},"PeriodicalIF":0.0000,"publicationDate":"1921-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3382/ps.0070073","citationCount":"3","resultStr":"{\"title\":\"Preliminary Note on the Correlation Between Age at First Laying, and Size of First Eggs in Pullets.*\",\"authors\":\"Lippincott William A.\",\"doi\":\"10.3382/ps.0070073\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Early maturity has been a cardinal point of selection since the time of Robert Bakewell, with whom systematic breeding of meat producing animals began. That, on a given ration, the quickest gains are the cheapest gains, is axiomatic among livestock breeders generally. That it holds for growth gains in chickens as for the larger farm animals there is little reason to doubt though a cursory search of the literature has failed to show exact and satisfactory data bearing on this point.</p><p>Rice (1915) has shown that there is an important relationship existing between earliness of maturity in White Leghorn pullets as indicated by their age at the laying of their first egg, and the rate and persistence of egg production. This relationship is of such a nature as to indicate that the earlier the age at which a Leghorn pullet begins to lay, the greater is the number of eggs . . .</p></div>\",\"PeriodicalId\":100836,\"journal\":{\"name\":\"Journal of the American Association of Instructors and Investigators of Poultry Husbandry\",\"volume\":\"7 10\",\"pages\":\"Pages 73-74\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1921-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.3382/ps.0070073\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of the American Association of Instructors and Investigators of Poultry Husbandry\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2666365119303709\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the American Association of Instructors and Investigators of Poultry Husbandry","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666365119303709","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Preliminary Note on the Correlation Between Age at First Laying, and Size of First Eggs in Pullets.*
Early maturity has been a cardinal point of selection since the time of Robert Bakewell, with whom systematic breeding of meat producing animals began. That, on a given ration, the quickest gains are the cheapest gains, is axiomatic among livestock breeders generally. That it holds for growth gains in chickens as for the larger farm animals there is little reason to doubt though a cursory search of the literature has failed to show exact and satisfactory data bearing on this point.
Rice (1915) has shown that there is an important relationship existing between earliness of maturity in White Leghorn pullets as indicated by their age at the laying of their first egg, and the rate and persistence of egg production. This relationship is of such a nature as to indicate that the earlier the age at which a Leghorn pullet begins to lay, the greater is the number of eggs . . .