Parturition intervals and distributions of parturitions by months of buffalo in Southern and South-eastern Brazil
| Autor: | J.C. De Souza, J.A. DeFreitas, P.B. Ferraz Filho, A.M. Jorge, A.A. Ramos, C.H.M. Malhado, W.R. Lamberson |
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| Jazyk: | angličtina |
| Rok vydání: | 2010 |
| Předmět: | |
| Zdroj: | Italian Journal of Animal Science, Vol 6, Iss 2s, Pp 593-596 (2010) |
| Druh dokumentu: | article |
| ISSN: | 1594-4077 1828-051X |
| DOI: | 10.4081/ijas.2007.s2.593 |
| Popis: | Reproductive rate is an important component of economic success in livestock production. Parturition interval (IEP) is a direct measure of the productivity of the animal. Long IEP reduce the number of calves produced per year. The objective this study was to determine the distribution of parturitions across month and to evaluate factors affecting IEP. The data included 7,588 parturitions of Murrah, Mediterranean and Carabobo buffalo from 10 herds in Southern and South-eastern Brazil. The analysis of distribution of parturitions evaluated the effects of month, year and their interaction on birth date of calves by using a Chi-Square test in SAS PROC FREQ (SAS Institute, Cary, NC, USA). Parturition intervals (n = 2,630) were evaluated using analysis of variance in SAS PROC GLM. The model for IEP included the fixed effects of season (December to May = 1, June to November = 2), year, season x year, sex of the preceding parturition, age of weaning of the previous calf, and herd. All sources of variation were significant (P |
| Databáze: | Directory of Open Access Journals |
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