Abstract

Abstract
Our study look place in esteem Algeria, It covered a period of 12 years (2003 to2015) , and focused on the evaluation of the profitability of dairy cattle farming, via a survey on the parameters of reproduction and milk production. It involved 17 farms with 701 cows spread over six wilayas in eastern Algeria, including the walleyes of El tarf, annaba, Skikda, Constantine, Guelma and Souk Ahras, mainly of the prim Holstein and Montbéliarde breed. The results obtained showed that the success rate at the first mating is 45%, the percentage of cows requiring more than 02 mattings is 18.84%. The average age at 1st calving 29 ± 3.97 months with 27.9 ± 3.02 months for full imported heifers, and 33.4 ± 4.01 months for heifers born in Algeria. The interval between calving 401 ± 57.6 days, the calving-1st projection interval 83.6 ± 36.1 days and the fertilizing calving-projection interval 110 ± 67.4 days. Average milk production is around 5,418 kg / cow / year, with production limits of 3,729 and 6,551 kg of milk. Overall, the fertility and fertility parameters are low, milk production is acceptable.
Investigations into the prevalence of diseases responsible for cow reform before the end of their career have shown that dairy cows are culled at 29.77% before the end of their career, mainly for locomotors problems (20.6% ), and clinical mastitis (16%), and to a lesser extent, poor milk production (14.5%), digestive disorders and infertility (11.4%; 10.7%). A study concerning the prevalence of subclinical mastitis was carried out on 58 Holstein dairy cows aged 3 to 10 years, distributed on 2 farms with a staff of 41 and 17 cows and on 164 and 65 milk samples taken respectively.
The results of the CMT test (California Mastitis Test), reveal on 229 districts a percentage of positivity of 62% of the samples (65.2% and 53.8% in each farm), increasing with the stage (beginning 40.9%, middle 65.62%, end 80.35%) and with the number of the lactation (first 48.73%, second 50%, third 68.05%, fourth 75%). In addition, milk control carried out on cows with the same number and lactation stage, showed a drop in milk production of around 9.7% on average in positive cows by contributions to negative cows.
The study of feeding practices, diet (distributed ration) has shown that the quantity of dry matter distributed is on average 17.69 kg, depending on the live weight of the cows and their milk production it is not far from the standard 16.6 to 17kg of MS. A very high average wastage rate 19.92% UFL and 49.69% PDI, mainly due to excessive use of the VL concentrate
Keywords: Dairy cow, reproduction, milk production, screening, CMT, East Algeria.

Information

Item Type:	Thesis
Divisions:	» Production animales, biotechnologie et sante » Institute of Agricultural and Veterinary Sciences
ePrint ID:	2524
Date Deposited:	2021-01-10
Further Information:	Google Scholar
URI:	https://www.univ-soukahras.dz/en/publication/article/2524

BibTex