Geographical isolation and human interventions resulted in formation of subpopulations among native breeds, which showed differences in morphological or biometric traits. Crossbreeding of indigenous goats with exotic breeds resulted in combining desirable characteristics of many breeds in a composite population. Malabari crossbreds (CB), which had the inheritance of Malabari, Saanen, Alpine and Boer goat breeds were available at University Goat Farm, Mannuthy, Kerala, India. The native goats of Kerala namely, Attappady Black (AB) and populations of Malabari goats from Kannur, Calicut, Thrissur and Malappuram districts (MK, MC, MT and MM) were analysed along with Malabari crossbreds (CB) for genetic diversity. Morphological data were collected from 1776 animals and biometric data from 572 animals representing six goat populations. Qualitative morphological traits analysed were coat colour, presence or absence of horns, tassels, beard, pattern of ear and hair at forequarters and hindquarters. Quantitative biometric traits assessed were chest girth, height at withers, body length and body weight collected from female animals of one to three years of age. Least squares means calculated from SPSS, canonical discriminant analysis by CANDISC, Mahalanobis distance and dendrogram constructed by PROC CLUSTER were used to analyse biometric variables. Canonical discriminant analysis conducted for biometric data identified three statistically significant canonical variables (P<0.0001), with CAN1 explaining 57.2 per cent of total variance. Multivariate analytical techniques thus confirmed the existence of six different populations. The discriminatory capacity of biometric variables chosen for the study was also justified.

: Growth is of great economic importance and requires particular attention for increasing total productivity in goat. The birth weight and early growth rate of animals are determined not only by genetic potential and also by maternal and environmental factors. Hence, an attempt has been made to know the effects of various non-genetic factors on the body weight at birth and different stages of growth. Data were collected from 180 goats belongs three genetic groups viz., Mablabari, Attappaddy and crossbred Malabari maintained at Goat and Sheep farm, Kerala Veterinary and Animal Sciences University, Mannuthy for the period from 2010 to 2013. The traits recorded were birth weight (BW), body weight at three (BW3), six (BW6) and nine months (BW9) of age. Birth weight (BW), body weight at three (BW3), six (BW6) and nine months (BW9) were analyzed to find out the effects non-genetic factors viz., breed, sex, season and type of birth using least square fixed model analysis of variance as described by Harvey (1990) for non-orthogonal data. Crossbred had significantly higher body weights at birth, three, six and nine months of age than Malabari and Attappady goat breed. However, the two native breeds of Kerala (Malabari and Attappady) did not differ significantly with respect to body weight at different stages of age. Season had significant influence on birth weight. Kids born as single had significant growth rate compared to twins and triplets upto nine months of age. KEY WORDS :Non-genetic factors, Malabari goat, Attappdy goat HOW TO CITE THIS PAPER : Venkatachalapathy, R. Thirupathy, Rojan, P.M. and Premkrishnan, G.N. (2015). Influence of non-genetic factors on body weight traits of goats reared in hot humid climate.

A study was undertaken to find out the morbidity and mortality pattern in the goat population of Kerala. Factors such as cause, age, sex, breed, season and year were included in the study. Data were collected from 3925 goats maintained at The Goat and Sheep Farm, KVASU, Mannuthy for six years from 2011 to 2017 to assess the effect of different factors. Data pertaining to 2649 goats from 2013 to 2017 were analysed to find out the morbidity pattern among goats. The overall mortality rate was 11.76 per cent. Among the various causes of mortality, the results of this study indicated that mortality due to enteritis was the highest (40.60 %) followed by that due to pneumonia (22.88%) and acidosis (10.40%). The effect of age, season, sex and year on goat mortality were significant (p<0.05). Mortality was the highest in the age group of 0.-3 months followed by 3-6 months. The incidence of mortality rates were 4.67, 5.09 5.27 and 5.26 per cent in pre-monsoon, south-west monsoon, post-monsoon and winter respectively. Mortality was more in females (64.11%) than males. Mortality was highest in cross bred goats followed by Malabari and Attappady black, but not significant. The proportional morbidity due to foot rot was the highest (35.28%) followed by enteritis (16.03%) and orf (7.65%). Highest morbidity was observed during south west monsoon (45.55%) followed by post monsoon (21.98%) and pre monsoon (18.14%). The results of this study suggest that proper management during first three months of age especially during south west monsoon was critical to minimise mortality among goats.

Tick infestation is a major reason for economic loss in livestock production in the tropical countries. However, animals show variation in resistance and susceptibility to tick infestation. Bos indicus breeds were reported to be more resistant to tick infestation than Bos taurus cattle. The present study aimed to identify polymorphisms in four quantitative trait loci (QTLs) that were stated to be associated with resistance/susceptibility to tick infestation, in a population comprising native Vechur breed (n=45) and crossbred cattle (n=74) of the Kerala Veterinary and Animal Sciences University farms. The QTLs were selected from the Animal QTL Database (https://www.animalgenome.org/cgibin/QTLdb/index). The single nucleotide polymorphisms (SNP) and the QTLs (in parenthesis) used in this study were: rs41661020 (#101148), rs43708490 (#135798), rs41577070 (#135800) and rs29009970 (#135801). Blood samples were collected from the animals, isolated the DNA and used for genotyping and polymorphism study by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism and confirmed by sequencing. The results revealed polymorphic pattern for the SNPs rs41577070, rs41664020, and SNP rs43708490 in both Vechur and cross-bred populations. The SNP rs29009970 was monomorphic in the crossbred cattle, whereas, dimorphic in Vechur. Genotyping was done by direct counting and the allelic and genotypic frequencies were estimated by POPGENE 1.32. Chi-square test revealed that crossbreds and Vechur were in Hardy-Weinberg equilibrium for SNPs rs41577070, rs41664020, and rs43708490, whereas, the SNP rs29009970 showed a significant departure from the equilibrium.

The present study aimed to evaluate the influence of various factors on the host resistance of cattle against tick infestation in Kerala State, South India. The number of naturally infested semi-engorged female ticks present on the cattle was counted on a sample cattle population across the four regions of Kerala. Then, the animals were grouped based on the tick count. The chi-square test and Fisher exact test were used to identify the effects of genetic and non-genetic factors on tick burden in cattle. It was found that the Holstein Friesian crossbred and Jersey crossbred cattle had a significantly higher level of tick infestation than the indigenous Vechur breed (Bos indicus). No tick infestation was observed in indigenous Kasaragod Dwarf cattle (B. indicus). Tick infestation was more in heifers and dry animals than lactating animals. However, the sex of the animal and the stage of lactation did not influence the tick load. Tick infestation was also influenced by parity, grazing, and region.