Research on Lifetime Mohair Production, Reproduction and Income of Angora Goat Ewes

Abstract

Angora goat ewes are expected to produce a lot of fleece and reproduce a lot during their lives. The identification of high producing ewes at an early age that will maintain their production levels throughout their lifetime in the flock is thus imperative. From 2000 to 2015, data on early and adult body weight, hair development, and reproduction were collected on the flocks of three South African Angora goat producers to determine the range in production, reproduction, and income of Angora ewes with five or six kidding opportunities in the flock. The relative contributions of hair development and reproduction to these ewes' income were also looked into. There were large differences in hair production, reproduction and income among ewes that had 5 or 6 kidding opportunities. It was clear when compiling lists of the top and bottom performing ewes for the adult productive traits that getting ewes that are top performers in all traits would be difficult. Top-producing ewes in terms of reproduction were not top-producing ewes in terms of fleece quality. The relative sources of income highlighted the negative relationship between reproduction and fleece development. When comparing the relative sources of income between ewes in the top and bottom income categories, it was clear that the main difference in overall yearly income was due to discrepancies in yearly reproduction income. It was further evident that reproduction income contributed more to total income in ewes in the top 25% income category compared to ewes in the bottom 25% category. When comparing the early and adult production and reproduction traits of ewes in the Top 100 Income and Bottom 100 Income lists, ewes in the Top 100 Income list had higher first parity reproduction, as well as lifetime reproduction, higher early body weights (from birth to 16 months of age), lower second shearing fleece weight and higher early fibre diameter than ewes in the Bottom 100 Income list. The negative relationship between adult ewe reproduction and fleece development emphasises the importance of not putting positive selection pressure on early fleece weight at the expense of reproduction. Only young ewes with unacceptably low fleece weights should be culled, and excessive selection pressure on early fibre diameter in ewes should be avoided. Selection for fleece production and fleece traits should rather be addressed through ram selection. Selection of young ewes should therefore be focussed on early body weight and weight of kids weaned at the first parity.