@article{MAKHILLAJ20149320639,
    title = {Relevance of Type of Breeding and Single Versus Double Sponge Inserts Followed by PMSG on Herri Ewes Estrus Exhibition and Pregnancy Rate},
    journal = {Agricultural Journal},
    volume = {9},
    number = {3},
    pages = {156-161},
    year = {2014},
    issn = {1816-9155},
    doi = {aj.2014.156.161},
    url = {https://makhillpublications.co/view-article.php?issn=1816-9155&doi=aj.2014.156.161},
    author = {Mohamed},
    keywords = {Ewes,estrous synchronization,FGA,pregnancy rate,sponge},
    abstract = {This study was designed to investigate effects of natural 
  mating versus artificial insemination in ewes synchronized for estrus/ovulation 
  by single versus double sponge inserts combined with PMSG. A 120 cyclic Herri 
  ewes were utilized in the study. The 10 ewes served as control (C), given no 
  treatment, 58 ewes were designed to be naturally mated at estrus exhibition, 
  47 of which were inserted with a single sponge impregented in Fluoro Gestone 
  Acetate (FGA) for 12 days and given 500 IU PMSG at sponge removal (SSNM-G1) 
  and 11 ewes were given Double Sponges (DSNM-G2), the 1st sponge lasted 7 days, 
  removed and replaced by a 2nd sponge for 5 days and at the 2nd sponge removal 
  500 IU PMSG was given (i.m). All ewes were visually observed for estrus signs 
  and at onset of estrus, fertile rams were allowed to mate ewes. Time from sponge 
  removal until estrus exhibition was recorded for each group. The artificially 
  inseminated ewes were randomly allocated into 2 group, SSAI (G3, n = 31 ewes) 
  and DSAI (G4, n = 21 ewes) in which ewes were given a single and double sponge 
  inserts, respectively. Animals in G3 and G4 were timed inseminated with chilled 
  fertile semen 48-50 h after sponge removal. All ewes were diagnosed for pregnancy 
  30 days post breeding by ultrasound. Proportion of ewes observed in estrus was 
  highest in DSNM ewes (100%), followed by SSNM (91.5%) compared with C ewes (70%). 
  Mean time interval from sponge removal till estrus was shorter in DSNM (38.1 
  h) than in SSNM (46.3 h). Likewise, conception and pregnancy rates were higher 
  in DSNM (81.8 and 81.8%, respectively) than in SSNM (74.4 and 68%, respectively). 
  Artificial insemination resulted in lower pregnancy rate (42.3%) with 35.4% 
  in SSAI and 52.3% in DSAI ewes. Mean pregnancy rate in control ewes was 50%. 
  In conclusion, inserting 2 sponges throughout 12 days combined with 500 IU PMSG 
  at sponge removal shortened the interval from sponge withdrawal till exhibiting 
  estrus, increased conception rate and pregnancy rate in Herri ewes.}
    }