Epsilon Archive for Student Projects

Abstract

A convenient method for efficient and successful hunting – in accordance with the animal protection laws – is the service provided by hunting dogs. Approximately 12 000 – 18 000 years ago humans domesticated dogs for hunting purposes (Braastad & Bakken, 2002; Sablin & Khlopachev, 2002; Germonpré et al. 2008). During the time of breed creation dogs were selected for certain traits like for instance hunting (e.g. tracking or flushing), guidance, and protection (Naderi et al. 2001). Still today selection and other breeding measures help to improve the performance (Holloway et al. 2011) of hunting dogs (Ruusila & Pesonen, 2004).

The aim of this project was to estimate heritability parameters for hunting performance traits evaluated in breeding tests. Data from standardized, breed specific hunting ability tests for German Hunting Terrier (GHT), a versatile small hunting dog breed, was available for the present investigation. The data covered records from performance tests of the past twenty years and pedigree data that traced back to breed creation.

GHT dogs have to participate in aptitude tests in order to be certified as breeding animals and as a cornerstone for further contribution in more advanced performance tests. Furthermore, after successful testing the dog can be authorized for hunting on state grounds and for professional hunting. As a result a large number of GHT dogs are tested in the above mentioned breeding tests.

The data provided by the breed club consisted of two datasets. The performance dataset involved four conformation traits, twelve performance traits, the individual ID number of the dogs, total amount of points from the tests including rewarded price, test date and test location. The original performance dataset included more than 14 739 observations. The pedigree dataset contained a total of 101 250 individuals with information on birthdate and the identification of their dam and sire. After merging of the two datasets and data editing the joint, adjusted dataset consisted of 9457 test records, which were the basis for the estimation of variance components.

Heritability estimates of the present analysis varied between traits and were generally low. The highest heritability of 23 % was found for the hunting trait Water affinity, while the performance of Reaction to shot had almost no genetic contribution (h2=0.01). The results from the genetic analysis were in line with findings of previous research, carried out for other types of hunting dogs, e.g., Liinamo (2004), Brenøe et al. (2002), Schmutz & Schmutz (1998) and Karjalainen et al. (1996). The conclusion behind the low heritability estimates is that different environmental effects (e.g., natural environment, age, system of testing and test evaluation or test location) strongly affect the performance in hunting aptitude tests. Reasons for the significant influences were discussed and some recommendations for improvement of hunting ability tests were made.