Linked Life Data

15483153

Source:http://linkedlifedata.com/resource/pubmed/id/15483153

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2004-10-14
pubmed:abstractText
The Assaf breed of dairy sheep, a stabilized cross of the Awassi and East Friesian breeds, has replaced the Awassi as the breed of choice in its country of origin, Israel, and has spread to other Mediterranean countries. In Israel the Assaf breed is managed under an intensive production system involving weaning lambs at birth, rearing them artificially, and milking ewes after parturition. There are several breeding periods in the year when ewes are mated following hormonally synchronized estrus. Records of 18,976 lactations from 5 farms were analyzed to investigate factors that influenced Assaf milk and reproductive performance. Lactation curves were fitted to each lactation, and a range of parameters and calculated values were analyzed. Daily milk yield records also were analyzed to describe a typical Assaf lactation and compared with those of the Awassi breed. Factors affecting age at first lambing also were studied. An average Assaf ewe kept under this intensive management regimen was found to produce 334 L of milk during a 173-d lactation. Mean litter size was 1.57 lambs/ewe lambing, and lambing interval was 272 d. Milk production was affected by litter size, with twin- and triplet-bearing ewes producing approximately 20 L more milk per lactation than single-bearing ewes. Day length was the major environmental variable influencing milk yield. The difference between midsummer and midwinter day lengths accounted for a difference in daily milk yield of 0.44 L in favor of summer. Ewe lambs that were mated for the first time at later ages produced more lambs and more milk due to greater early lactation characteristics. Milk production was found to be negatively associated with subsequent reproductive performance. Comparing these results with those from an earlier study in the Awassi breed, the Assaf was found to produce less milk during a shorter lactation than the Awassi, but its greater litter size made it a more profitable breed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-0302
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3690-703
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Reproductive performance and milk production of Assaf sheep in an intensive management system.
pubmed:affiliation
Department of Agricultural Sciences, Imperial College London, Wye campus, Ashford, Kent, TN25 5AH, UK.
pubmed:publicationType
Journal Article