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ThesisItem Open 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 CAn 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.ThesisItem Open 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 KThis 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.ThesisItem Open Access Statistical models in growth studies of rabbit(Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1997) Manojkumar, K; KAU; George, K CAn 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.ThesisItem Open 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 CAn 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 .ThesisItem Open 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 KA 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.ThesisItem Open Access Comparative study of lactation curves in goats(Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1991) Anita, S; KAU; George, K CBased on the weekly milk yield data of 20 weeks duration over different parities of the seven yenetic groups viz. Alpine Malabari, Malabari, Saanen Malabari, F2A , F2S, F3A and F3S maintained at the KAU, Goat Farm during the period 1976-'87, the following objectives were investigated. 1. To fit various lactation curve models in different breeds of goats and to select the most suitable one 2. To suggest a procedure for predicting complete lactation yield using various part lactation yields, 3. To study the effect of genetic and non-genetic factors on milk production traits. 4. To compare the persistency of milk yield among the selected breeds. On the basis of the criterions I, r and s eleven types of fitted lactation curves were compared. Among the curves compared the quadratic-cum-log and linear hyperbolic functions were selected as the best two curves for the genetic groups,Alpine Malabari, Malabari, F2A, F2S, F^A while for genetic groups Saanen Malabari and F^S the linear hyperbolic and quadratic log scale functions were the best two selected curves. As the linear hyperbolic function was found to be suited for all breeds under study it was selected as the best fitted curve for goats. Taking various cumulative part records of 4, 8 and12 weeks the linear hyperbolic function was then fitted to the parity-wise and pooled data of the seven genetic groups. It revealed that efficiency of over 98 per cent was achieved for all the part records though the efficiency increases with each added part record and hence this function could be selected as a prediction equation for the prediction of total yield from part record. Based on the ANOVA obtained by a two way classified non orthogonal data analysis the breed, order of lactation and their interaction were found to have significant influence on average yield. Among the breeds Saanen Malabari and among the parities fourth parity were found to be significantly different from the others and have the highest average weekly yield. Among the four methods used for comparing the seven genetic groups by calculating the persistency index, three methods (except method II) gave Saanen Malabari as the highest persistent one. By method II the highest index was attained by F^S followed by Saanen Malabari. Since Saanen Malabari gave the highest yield for pooled and individual parity data it was selected as the most persistent and high yielding breed.ThesisItem Open Access Pooled analysis of dependent sets of data(Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1991) Sukumaran, K; KAU; Gopinathan Unnithan, V KA new methodology for the analysis of data generated from experiments in which observations constitute repeated measurements from the same experimental unit at different points of time was developed. The problem of dependence of error terms in successive observations was taken care of in the model for analysis itself. The model included regression of error terms on those in the yester years/seasons. The error mean square from this model was derived using principle of least squares. The proposed method was compared with the widely adopted split-plot analysis and its superiority discussed. The method was illustrated using data generated from an experiment conducted to compare three varieties of alfalfa laid out in RBD with six replications and observations taken in four consecutive seasons. The superiority of the new method over the split-plot analysis was evident in the example considered.ThesisItem Open 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 CAn 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. t.o find a suitable relationship between age and body weight. 2. to investigate the trend of egg production i n 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 I identical management practices (recommended by Kerala Agricultural University Package ;of Practices). The investigation mainly depended on data consisting of weekly body weights of individual birds, daily egg production of birds (beginning from age at sexual maturity) and daily climatological parameters (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 determination (r^) and standard error of estimate(s). Mathematical models such as linear, exponential, parabolic exponential, inverse polynomial, Gamma function, Gamma-type functicn, quadratic function, quadratic function in logarithmic 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 . 2 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 diimatological parameters on egg production in quails.ThesisItem Open Access Influence of weather parameters on the yield of black pepper(Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1990) Dessy Mabel; KAU; Gopinathan Unnithan, V KInfluence of weather parameters on the yield of black pepper was studied utilising the data on yield of 29 varieties of pepper (Pipger nigrum) and maximum temperature, minimum temperature, relative humidity, rainfall and number of rainy days recorded from 1963-64 to 1979-80 at The Pepper Research Station, Kerala Agricultural University, Panniyoor, in the Cannanore District of Kerala. Averages/totals of weather elements for standard weeks as well as for fortnights during the critical period of crop growth viz, from April 9 to August 12 were determined. Correlation coefficients of all the weather elements of standard weeks and fortnights with annual yield when represented in correlograms revealed, wide variations in response of different varieties to changes in climatic factors among the 29 varieties. In other wards there was definite evidence of genotype - environment interaction. Forcasting models, based on weekly as well as fortnightly weather elements were estimated for each of the 29 varieties of black pepper by two stage linear regression technique. First stage models were estimated by multiple linear regression and the second stage models were estimated with the estimates of yield from first stage models as explanatory variables by step-wise regression technique. The forecasting models utilising weekly climatic data had higher predictability compared to that utilising fortnightly data. All the final forecasting models with weekly data had predictability of 98% and above. More over the first stage models, from weekly data, could also be used to forecast yield of all varieties of black pepper with remarkable accuracy.
