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In the past decade, recognition of the possibility of using genetic selection as a tool forimproving disease resistance in dairy cattle has been hypothesized as a useful tool by both researchersand producers alike. Specifically, many studies have investigated the influence of genetics in commondiseases of the dairy cow (Shanks et al., 1982; Lin et al., 1989; Lyons et al., 1991; Uribe et al., 1995;Zwald et al., 2004; Heringstad et al., 2005). To date, there has been limited research published on thegenetic effects of common diseases in dairy calves. The few published studies, pertaining to this topic,have focused on the genetics of respiratory disease in Norwegian Red Holsteins (Heringstad et al.,2008) and in various breeds of beef calves (Snowder et al., 2005) .Preweaning calf diseases are a very costly concern for dairy producers. In addition, theseproblems are an important issue in terms of animal welfare. Furthermore, preweaning diseases havebeen associated with increased risk of morbidity later in the rearing period, and are likely to haveimpacts on the mature life of the animal, such as increased age at first calving and decreased lifetimeprofitability (Walter-Toews et al., 1986; Svensson et al., 2006). For instance, it has been shown thatheifers treated for pneumonia within 90 days of birth were more likely to die after that time, ascompared to untreated calves (Walter-Toews et al., 1986). Also, calves contracting navel-joint illnessin early calfhood have exhibited significantly shorter herd longevity patterns, compared to calvesreceiving no treatment (Britney et al., 1984). In addition, calfhood diarrhea has been associated withlowered first lactation milk production (Svensson and Hultgren, 2008). The occurrence of diarrhea isstrongly associated with respiratory disease, which is known to generally have longer convalescenceand more profound effects on rate of growth (Lundborg et al., 2003). In spite of the reported lowheritabilities of most health traits, genetic variation of calfhood disease is of potential economicimportance. As such, inclusion of these traits in breeding programs could be valuable.Markedly variable calfhood morbidity rates (prior to weaning) have been reported from a widevariety of sources and study designs. In a review by Shook (1998), it was stated that genetic studies ofcalfhood diseases in commercial herds were nonexistent, and concluded that more knowledge wasneeded for making decisions about the inclusion of these traits in breeding programs (Shook, 1998).To date, the only routinely evaluated traits, which include information concerning calves, in Canadianand US national dairy cattle breeding programs are Calf Survival and Stillbirth, respectively. Theobjectives of this research were to estimate genetic parameters for 3 preweaning diseases (respiratorydisease [BRD], umbilical diseases [UMB], bloat [BLT]) for a population of calves from New YorkState, as well as to associate sire proofs for these 3 calf heath traits with traits routinely evaluated inCanada and US.
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