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Subject: Agricultural Statistics and Informatics × End date: 1989 × Start date: 1989 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Comparative study of growth pattern in ducks - a practical approach
    (Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1989) Vishnu Namboodiri, M; KAU; George, K C
    An investigation based on 14 Desi males, 25 Desi females, 26 White Pepkin (WP) males and 26 WP females belonged to the Kerala Agricultural University Duck Farm, Mannuthy was undertaken (i) to examine the pattern of growth in the two breeds of ducks (ii) to compare the rates of growth between and within each genetic groups and (iii) to fit appropriate growth curves for prediction of body weight at different stages of growth. The ducklings were reared under uniform feed formula and identical management practices. The initial mean body weights of the six groups of ducklings viz. Desi males, Desi females,WP males, WP females, Desi ducklings irrespective of sex and WP ducklings irrespective of sex were 36.6428 g, 38.16 g, 38.6538 g, 38.3486 g, 37.6153 g and 38.4423 g respectively. Females in each genetic groups had a higher mean body weight than males except 11th and 12th week in the case of Desi ducklings. On the 12th week the body weight averaged 1291.7857 g, 1239.4 g, 1021.7308 g, 1401.6154 g, 1258.2051 g and 1214 g for Desi males, Desi females, WP males, WP females, Desi ducklings irrespective of sex and WP ducklings irrespective of sex respectively. The initial body weight was non significant for all the four groups whereas the 4th, 8th and 12th week body weights showed significant difference between groups. It could be observed that a plateau in body weight was not attained on the 12th week of age for Desi and white pepkin ducklings. Gompertz (y = abcx), modified exponential (y = k+abx) and Von-Bertalanffy (yt = A(1-be-kt)3 were found suitable for fitting body weights for the first 12 weeks. The first two gave good fit to almost all birds on individual and average basis. When the growth rates of the fitted curves were compared, Gompertz curve showed significant difference between groups. The maximum growth rate was noticed inDesi females. Based on modified exponential and Von-Bertalanffy the rate of growth was significant and maximum growth was noticed for WP males. By the method of Rao (1958) the initial body weight had significant relation with the growth rate (b). The rate of growth was maximum for WP females followed by Desi females. The graphs of the best fitted curves – Gompertz, modified exponential and Von-Bertalanffy were drawn for all the six groups along with the observed values and that also confirms the above findings.