Importance of Cross Breeding in Farm Animals
CROSS BREEDING:
This is mating of animals from the two different established breeds
Eg.: Jersey (b) x Kangayam (c) : Jersey (c) x Holstein Friesian (b). The cross bred animals
will exhibit the mixture of qualities of both the parents breeds. The progeny will improve in
production performance and will exhibit marked disease resistance characteristics of
the native breed and is well adpated to with mstand local climatic condition. 62.5% of exotic blood & 37.5% local blood – ideal .
Jersey x local breed.- F1- 50% ND(c) x J (75%) + 25% ND – F1 50 J 50 ND x 100 J (B) So cross breeding is also taken up to evolve new breed.
Age at maturity Economic traits
1.Age at 1st calving : Age in days of the cow or buffalo on the date of 1st calving.
- Lactation Length : Days in milk from the date of calving to the final drying off or
or cessation of milk (305 days) - Lactation Yield : Milk yield in Kgs from the date of calving to the date of drying (corrected to 305 days)
- Dry period : Days from the date of drying to the date of calving
- Inter calving period: Days from the date or one calving to the date of next calving (1st,2nd )
6.Peak yield : The highest daily yield in Kgs during lactation period
- Average Fat% : Average Fat %
8.Service period : The interval between calving and subsequent service resulting in conception
9.Breeding efficiency : Measured as the No. Services/Conception
Breeding : Production of off springs / young ones
Scientific breeding is needed to get better performance in livestock – milk – meat – wool – Egg
Inbreeding : mating of closely related animals in the same breed such as brother – sister mating
ii. parents off spring mating- when the mates have common ancestors -with in generations this results in inbreeding
Advantage : A pure line of a particular breed can be maintained
Dis advantage : Loss of vigour, size, production fertility problems
Out breeding : Mating of unrelated animals in the same breed but with no common ancestor for a minimum of 4-6 generations.
Grading : Grading is a farm of out crossing, where in bulls of a distinct breed are bred on non descript cows from generation to generation, so that in course of time a populations essentially resembling the breed from which the Bulls are used.
Non descript cow x Jersey Bull
F1 50% ND + 50% Jersey x Jersey Bull
F2 25% ND + 750% Jersey x Jersey Bull
F3 12.5% ND + 87.5% Jersey x Jersey Bull
After 5-6 generations the off springs will have 96.9 & 98.3% of the hereditary characters of
„Pure Breed‟
So grading is a process by which a few „Pure Breed‟ sires can rather quickly transform
local variety of animals into a „Group‟ resembling the pure breed.
Economic Traits
