Heritability Estimates of Body Weight and Linear Body Measurements in Goats Under Smallholder Farming Systems

CHAPTER ONE

1.1 Background to the Study

Goat production plays a vital role in the livelihood of smallholder farmers, especially in tropical and sub-tropical regions. Goats provide meat, milk, skin, and income, making them an important component of rural economies (Devendra, 2012). However, productivity is often constrained by low genetic potential and poor management practices. Understanding the heritability of traits such as body weight and linear body measurements is crucial for genetic improvement programs.

Heritability measures the proportion of variation in a trait that is due to genetic differences among individuals. Traits with high heritability respond quickly to selection, leading to genetic improvement (Falconer and Mackay, 1996). According to Yakubu (2010), linear body measurements such as chest girth and body length are reliable indicators of growth and body condition in goats. This study aims to estimate heritability for body weight and related traits among goats managed under smallholder systems.

1.2 Statement of the Problem

In Nigeria, goat breeding is mostly unplanned, and selection is based on visual appraisal rather than scientific evaluation. This practice limits productivity and genetic progress (Adu et al., 2019). There is inadequate information on heritability estimates of body weight and body measurements in goats under smallholder conditions, which hinders the development of structured breeding programs.

1.3 Objectives of the Study

1. To evaluate body weight and linear body measurements of goats under smallholder farming systems.

2. To estimate the heritability of these traits.

3. To identify traits that can serve as selection criteria for genetic improvement.

1.4 Research Questions

1. What are the average body weight and linear measurements of goats in smallholder systems?

2. What is the heritability of these traits?

3. Which traits are most suitable for selection in breeding programs?

1.5 Significance of the Study

The findings will help farmers and animal breeders identify measurable traits that can improve goat productivity through selection. It will also provide a scientific basis for developing sustainable breeding strategies for local goat populations.

1.6 Scope and Limitation of the Study

The study will focus on goats raised under smallholder systems in selected rural communities. It will cover phenotypic and genetic evaluation of body weight and linear body measurements.

1.7 Definition of Terms

• Heritability: A measure of how much genetic factors contribute to the variation of a trait.

• Linear Body Measurement: Physical dimensions of the body such as body length, height, and chest girth.

• Smallholder System: A low-input farming system practiced by rural households.