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  • ThesisItemOpen Access
    Development of a suitable model for ascertaining the growth and egg production in quails
    (Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1991) John Thomas, M; KAU; George, K C
    An investigation was carried out into the growth and egg production aspect of Japanese quails at the Kerala Agricultural University Poultry Farm, Mannuthy on 1st February, 1989 with the following objectives. 1. to find a suitable relationship between age and body weight. 2. to investigate the" trend of egg production in quails through suitable mathematical models. ,3. to study the impact of climate parameters (temperature, ; , humidity) on egg production in quails. The birds were reared under uniform feed formula and ^identical management practices (recommended by Kerala Agricul tural University Package of Practices). The investigation mainly depended on' data consisting of weekly body weights of -ii^-dividual birds, daily egg production of birds (beginning from age at sexual maturity) and daily climatological para meters (temperature and humidity) from beginning till the end of experiment of 30th September, 1989. Mathematical models such as linear, quadratic, exponential, .Von-Bertalanffy, modified exponential, logistic and Gompertz were fitted for the purpose using body weights of ) individual birds as well as average body weights over twelve weeks and the fitted models were compared using coefficient of 2 determination (r ) and standard error of estimate(s). Mathematical models such as linear, exponentialf parabolic exponential, inverse polynomial. Gamma function. Gamma-type functic^n, quadratic function, quadratic function in logari'thmic scale, quadratic-cum-log, emperical and linear hyperbolic functions were fitted for the development of suitable models for ascertaining egg production using total weekly, fortnightly egg production, hen housed and hen day egg production and fitted models were compared using Furnival index, r^ and s. Multiple linear regression equation was fitted using average weekly egg production per bird as dependent variable and weekly temperature and humidity as explanatory variable to study the impact of climatological parameters on egg production in quails. The investigation has the following, salient features. (i) The hatching weight of Japanese quails were 7.1369 g. (ii) The females weighed more than the males during the entire period of experiment and the body weights have shown an increasing trend. At the end of 12th week the average body weights of males and females were 157.6552 g and 179.2500 g respectively. (iii) Rao's method justified that initial body weights • had no significant effect on growth rate. • (iv) Gompertz curve = a exp [-b exp(-kt)'] was most , suitable for , ascertaining growth in quails on individual basis as well as on the basis of • average body weights over twelve weeks. (v) Average age at sexual maturity (females) was found to be approximately 10 weeks and on an average the eggs weighed 12.20 g. (vi) Quadratic function in logarithmic scale ; = a f b(logJ^) + c(log^)^ was most suitable , for ascertaining egg production in quails (weekly, , fortnightly, hen housed and hen day production • basis). (vii) Climatic parameters had significant impact on egg production in quails.
  • ThesisItemOpen Access
    Study of genetic correlations under full -SIB mating system (Two loci case)
    (Department of Statistics, College of veterinary and animal sciences Mannuthy, Thrissur, 1985) Khin Moe Moe; KAU; George, K C
    A purely theoretical investigation entitled ,JA Study of Genetic Correlations under Fu ll-s ib Mating System (two lo c i case)*1 was carried out with the following objectives, i ) to derive the joint distribution (correlation table) and to find the correlation between fu ll -s ib pairs under fu l l -s ib mating system in the case of two lo c i when there i s no linkage as well as when there i s complete linkage. l i ) to derive the joint distribution (correlation table) and to find the correlation between parent-offspring pair© under fu l l -s ib mating system in the case of two loci when there is no linkage as well as when there is complete linkage, i i i ) to derive the joint distribution (correlation table) and to find the correlation between fu l l -s ib pairs under paront-offspring mating system in the case of two lo c i when there is no linkage as well as when there is complete linkage, iv) to derive the joint distribution (correlation table) and to find the correlation between parent-offspring pairs under parent-offspring mating system in the case of two lo c i when there is no linkage as well as when there is complete linkage. 2 Th© joint distributions of fu ll -s ib pairs and parent- ©Ffspring pairs undor fu ll-s ib gating system wore derived with the help of generation matrix technique and th© correlations wore worked out therefrom, assuming additive genie e ffec ts and using the product-momeni correlation coefficient formula. The correlations were worked out for tho f i r s t ten generations of fu ll -s ib mating in both cases of no linkage and complete linkage, & comparative study of fu ll -s ib correlations and parent-offspring correlationsf conducted both numerically and graphically, revealed that £i) evonthough fu ll -s ib correlation was greater than parent-offspring correlation in in i t ia l generation (random mating) when there was complete linkage, the la tte r increased more rapidly than the former from in it ia l generation to f ir s t generation and ( i i ) from the second generation onwards, the rate of increase in both o f correlations were nearly the same upto tenth generation. I t was interesting to note that the parent-offspring correlations wore of comparatively higher order than th© fu ll-s ib correlations in both cases of complete linkage and no linkage. Similarly, th© joint distributions (correlation tables) for fu ll-s ib pairs and parent-offspring pairs under parentoffspring mating system were derived employing generation matrix approach and the correlations for the f i r s t ten 3 generations of parent—offspring mating in both cases of no linkage and complete linkage were worked out therefrom. A comparative study of those correlations was carried out both numerically and graphically. It was found that the trend in both correlation curves remain the same, but the value of parent-offspring correlation was always greater than that of full-sib correlation in case of no linkage as well as in caso of complete linkage. In comparison of all these correlations, it was found that the correlations increased as the number of generation increased and ultimately reached the limit unity when the number of generations increased indefinitely large. It was also observed that the magnitude of correlation in case of complete linkage was more than that of correlation In case of no linkage even under the same system of mating*
  • ThesisItemOpen Access
    Study of Genetic Diversity in Desert and Culinary Types of Banana Varieties
    (Department of Statistics,College of Veterinary,Mannuthy, 1981) Mercey, K A; KAU; George, K C
    The data taken from the Bana Research Station, Kannara for 30 culinary varieties for 13 morphological characters and 56 dessert varieties for 12 morphological characters were the base material for this study. Genetic divergences in the varieties were studied using D2-statistic and canonical analysis. The varieties were grouped into clusters by using Tooher’s minimum generalized distance concept. The same clustering pattern was obtained through canonical analysis. In the case of culinary varieties 12 clusters were formed consisting 11 varieties in the first cluster 5 each in second and third and the others were single variety clusters. Whereas the dessert varieties were grouped into 7 clusters 13 varieties in the first cluster 17 in the second cluster, 20 in the third, 2 each in the fourth and fifth and the last two were single variety clusters. The intra and inter cluster distance were diagrammatically represented in a two dimensional space. The scatter diagram showing the mean values of the canonical variates in order to have an idea of the appropriateness of the clustering pattern were also formed in both the type of varieties. In the case of culinary varieties the character bunch weight and in the case of dessert varieties the character finger length was contributing maximum towards divergence. The character girth was contributing minimum towards divergence in both the cases.
  • ThesisItemOpen Access
    Optimum size of plots In coconut using multivariete techniques
    (Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1997) Kumari Liji, R S; KAU; Gopinathan Unnithan, V K
    This investigation was taken up to determine optimum size of experimental units for coconut using multivariate approach. Observations on yield, female flower production, percentage of buttons set and number of functional leaves from 184 coconut palms for two consecutive years were utilised. These palms belonged to two separate experiments in two locations. All known systematic effects were eliminated from the observations. The trees were arranged in the ascending order of the number of functional leaves of first year of observations. Experimental units of sizes ranging from single tree to ten trees were formed by combining trees adjacent in the list of ordered trees. Blocks of five plots, seven plots and ten plots were also formed by combining adjacent plots. Coefficient of variation in univariate case and determinant of relative dispersion matrix in multivariate case were the measures of variation used. Optimum size of experimental units was determined in univariate case for yield and female flower production in first and second years. Optimum size of plots was determined in multivariate case for the following character combinations. 1) Yield for first and second year 2) Female flower production for first and second years 3) Yield and female flower production for first and second year 4) Yield, female flower production and percentage of buttons set for the first year 5) Yield female flower production and percentage of bottons set for the second year Optimum size of plot was determined by three different criteria viz., (i) that which requires minimal experimental material for a specified precision (ii) that having maximum efficiency and (iii) that which maximises the curvature of the relationship between measure of variation and plot size. Plot size that required minimum number of trees for 5 per cent error was two tree plots except in the univariate case of yield in first year and multivariate case of without blocking for characters sets (4) and (5) for which single tree plots were optimum. In all univariate determinations single tree plots had maximum efficiency. Two tree plots had maximum efficiency in multivariate approach except for characters sets (4) and (5) in the case of no blocking. Four tree plot was optimum by the method of maximum curvature except for characters sets (3), (4) and (5) is multivariate case for which three tree plots were optimum. Though Fair Field Smith's law was a good fit to the relationship between the measure of variation and plot size, Y = a +b/√x+ c/x gave better fit in most of the cases. Two tree plots were recommended for experiments it) established coconut gardens.
  • ThesisItemOpen Access
    Statistical models in growth studies of rabbit
    (Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1997) Manojkumar, K; KAU; George, K C
    An investigation was undertaken in the Kerala Agricultural University Rabbit Research Station, Mannuthy to find a suitable relationship between age and body weight of three different breeds of rabbit viz. Newzealand White, Soviet Chinchilla and Grey Giant and to study the impact of climatic elements, temperature and humidity on body weight. The rabbits were reared under uniform feed formula and identical management practices. The investigation mainly depended on data consisting of weekly body weights of rabbits up to twelve weeks and daily climatological parameters, temperature and humidity. The experiment was conducted during the three time periods (First time period: October to January, Second time period: February to May and Third time period: June to September). Seven mathematical models such as linear, quadratic, von-bertalanffy, exponential, modified exponential, logistic and gompertz were fitted for body weights of individual rabbit as well as average body weights over twelve weeks and these models were compared using coefficient of determination (R2) and standard error of estimate (s). Additive model, Wt = a + b L + c G and Multiplicative model, Wt = a Lb GC were fitted for developing a suitable relationship of average body weights, body lengths and body girths over twelve weeks of the three breeds. Using the average weekly dry bulb temperature and wet bulb temperature, Temperature Humidity Indices [THI = 0.72 (Cdb + Cwb) + 40.6 ] were worked out. Correlation coefficients between average daily weight gain per week and THI were worked out for finding the effect of climatological data on body weight. The investigation was having the following salient features. 1. In the time period, October to January the body weight of Newzealand White is significantly different from that of Soviet Chinchilla and Grey Giant. New Zealand White has lower body weight. But the difference-in body weights between Soviet Chinchilla and Grey Giant was not significant. In the second time period, February to May and in the third time period, June to September the difference in body weights of three breeds were not significant. 2. Von bertalanffy model, Wt = a [1 - b Exp(kt)]3 was the most suitable for ascertaining growth in the three breeds of rabbits on individual basis as well as on the basis of average body weights over twelve weeks. 3. The multiplicative model, Wt = a Lb Gc was obtained as the suitable relationship of body weight, body length and body girth of the three breeds of rabbit. 4. During the periods October to January (Winter) and June to September (Monsoon), temperature and humidity had significant effect on body weight. In the former period body weight will decrease along with increase in temperature and in the later period it will increase along with temperature.
  • ThesisItemOpen Access
    Construction of a composite sow inded and study of its effects due to sire, parity and season in pigs
    (Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1995) Gini, Varghese; KAU; George, K C
    An investigation was done for the constructions of composite sow index based on the data collected from sow cards of pigs maintained at the University Pig Breeding Farm, Mannuthy, with the additional objectives of studying the effect of sire, parity and season on this index and also to suggest for culling the uneconomic animals based on this index. Data were collected from 255 pigs selected under the first parity for the characters age at farrowing , post weaning conception period, litter size at birth, average weight of a piglet at birth, litter size at weaning and average weight of a piglet at weaning. The data were collected for the subsequent parities also for the above mentioned characters, from among the 255 sows selected. Three different types of selection indices were worked out viz. phenotypic index based on one main character and one auxiliary character, phenotypic index based on one main character and two auxiliary characters and a composite sow index. While comparing the phenotypic indices, it was found that the indices based on the characters litter size at weaning and average weight of a piglet at weaning were the most contributing characters along with age at farrowing and post weaning conception period. The variances of the composite sow index was less than that of the other two indices for all the five parities. Hence the composite sow index was selected as the most efficient index. Therefore, the best 25 animals were sorted out for each parity based on the composite sow index and used for further analysis. The best sow-sire pairs under each parity were identified by comparing the ranks of the three types of indices coming within the first 25. The seasonal effect on various characters considered was also tested by classifying the best ranking 25 sow – sire pairs into these seasons namely, winter season, summer season and rainy season under each parity. The average index under each season was compared by using the analysis of variance and it was found that there is no seasonal influence on any of the six contributing characters. The sows repeatedly coming under most of the parities were sorted out from the best 25 sows selected based on the composite sow index. The average values for the index and also for all the contributing characters under different parities were compared with the normal values of a standard sow and 07/160 was selected as the best sow. Similarly, 01/182 was selected as the best sire and 07/160-01/182 was chosen as the best sow-sire pair. An attempt was done to find out the best parity also. For this the sows came under at least for the first three parities were sorted out and their mean index values were compared using the analysis of variance test. No significant difference was observed for any of the parities. Being the most efficient index, the standard value for the composite sow index should be around six. Hence it can be concluded that the sows showing an index value less than 6 can be culled and nearer or greater than 6 can be retained for further breeding .
  • ThesisItemOpen Access
    Designs balanced for residual effects
    (Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1984) Sathianandan, T V; KAU; George, K C
    The usual problem in long term experiments is that due to residual effects of treatments. The effect of a treatment that persists for a period after the application of the treatment is referred to as residual effect of that treatment. In the present study an attempt is made to construct designs which will balance for first order residual effects to suit the above mentioned situations. By definition a design is said to be balanced if every treatment follows every other treatment equally frequently. We have established three different methods of construction of such type of designs. The first method of construction is by using cyclic latin squares as in the line of Amble (1977) and we have shown that such an arrangement is balanced for first order residual effects. The second method of construction is based on the set of (v-1) orthogonal latin squares of order v in the case of v treatments. A third method of construction of designs balanced for first order residual effects is also given. This is based on the procedure given by Nair (1967) for the construction of designs balanced for pairs of residual effects. A general intuitive method of analysis is also given.
  • ThesisItemOpen Access
    Influence of weather parameters on yield of coconut
    (Department of Statistics, College of Veterinary & Animal Sciences, Mannuthy, 1985) Pankajakshan Nair, B; KAU; Gopinathan Unnithan, V K
    Influence of eighteen climatic factors for a period ranging from 10-45 months before harvest of coconut, were studied on monthly and annual coconut yield. Monthly climatic factors showed a seasonal relationship with monthly yield changing sign alternatively. Month-wise and season-wise climate and their influence on monthly and annual yield was also studied. The influence of climatic factors were more in evidence during pre and post monsoon seasons. RH, SSH and EV are frequently showed significant relationship with monthly yield than the rest. Seasonal grouping of climate showed stronger relationship on annual yield than month-wise climate. May, September, October and December months of yester years showed explicit association with annual yield.
  • ThesisItemOpen Access
    Clustering genotypes based on G x E interaction in the absence of homogenecity of error variances
    (Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1992) Chandrika, C; KAU; Gopinathan Unnithan, V K
    A distance function between every pair of genotypes which measures the genotype-environment interaction in the case of heterogeneity of error variances in different environments was derived herein. A dissimilarity index for any set of genotypes which also measures the within group genotype-environment interaction sum of squares in terms of the pairwise distance function was also derived. Two methods of clustering, viz., statistical clustering and clustering by minimisation of average within cluster genotype-environment interaction making use of the proposed dissimilarity index were also proposed. Statistical clustering helps to group the genotypes such that genotype-environment interaction within any group is insignificant while any addition to the cluster makes it significant. In other words the idea of statistical clustering is to identify genotypes having similar response to varying environments. A point to be noted is that all the groups formed by statistical clustering may not be non overlapping. The other procedure helps to form optimum clustering by minimising the average within cluster genotype-environment interaction using an. iterative relocation algorithm. These clustering procedures were illustraited making use of two sets of data.