Morphology and its relationship with reproduction and milk production in goat and sheep
Morphological characterisation and multifactorial analyses of conformation traits in relation to productivity indicators are critical in goats and sheep breeding programs in particular, as the desired outcome could instigate animal performance change through indirect selection based on the phenotypic measurements. Animal morphology development is complex biological process probably with multiple genes being at play, which might be dependent on the environment, and changing over time, hence recording multiple descriptive morphological dimensions can make relating genotype to phenotype more feasible and, importantly, more relevant in terms of understanding functionality of domestic animals. Morphological traits sometimes referred to linear type traits, biometric, zoometric and conformation traits (measurements) have been of interest in both livestock and poultry production. Due to the fact that some morphological traits are highly correlated to performance traits, their application in animal production among other aspects include: prediction of growth rate, body condition, carcass and milking capacity. This implies that morphological traits correspond to functionality of animals for the purposes of production as a result they have been a useful tool in selection of animals, especially where records are unavailable. Morphological traits can be extremely valuable in animal breeding decision making since they can be used to derive specific scores for heritable traits. In most cases, in view of simplicity of measurement, morphological traits have been part of performance recording appraisal systems. This has worked well to overcome the gap that exist in keeping performance records especially in community based breeding schemes. In most cases records in smallholder production systems are unobtainable hence morphological dimensions become handy for selection purposes. Some of the morphological traits have proved to be the source or representative group of suitable selection markers to elaborate the appropriate breeding program to improve the reproduction and milk production potential of goats and sheep. If morphological traits are to be regarded for incorporation in prospective goat and sheep breeding programs, the relationship between them and reproduction and milk production need to be established. In the advent of multiple regression models the prospects are high to establish correlation analysis between morphological traits with production traits in goats and sheep. In conclusion, the review verified that morphological traits can be used as accurate indicators of animals’ reproductive capacity and milk production potential in goat and sheep production. The purpose of the present review is to highlight the relationship between morphometric characteristics and reproductive and milking potential in goats and sheep production.
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