@conference {40253,
	title = {Factors influencing the success of a large scale artificial insemination programme in sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {50},
	year = {1990},
	month = {Jan},
	pages = {427-430},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Two experiments were conducted to compare PMSG injection to GnRH   infusion for induction of breeding in anoestrous ewes. In Experiment   One, sixteen Suffolk ewes were pre-treated for 14 days with 30 mg   Cronolone sponges. At sponge removal half of the ewes received 0.125   ug/hr GnRH for 72 hours via subcutaneous osmotic pumps. The other half   received a single injection of 750 iu PMSG. Plasma LH levels gradually   increased and were sustained for 24 hours. Estrus, ovulation and   corpus luteum function were expressed in half of the ewes treated   with GnRH. All ewes treated with PMSG exhibited estrus, ovulated and   formed functional corpora lutea.     In Experiment Two, 24 ewes were divided into two groups and the same   treatments as in Experiment One were applied. Fertile rams were   introduced to all the ewes at the time of sponge removal. Estrus was   detected in 75\% of the GnRH treated ewes vs 100\% in PMSG treated ewes.   Lambing rates were 44\% and 56\% in GnRH and PMSG groups respectively.     These results suggest that the induction of fertility using continuous   infusion of GnRH is encouraging. However, other GnRH delivery systems   should be investigated.    },
	issn = {1176-5283},
	author = {Shackell GH and Kyle B and Littlejohn RP}
}
@conference {40032,
	title = {Haemoglobin type and prolificacy in Booroola sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {46},
	year = {1986},
	month = {Jan},
	pages = {237-240},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Groups of 33 Coopworth ewes were drenched with either 25mg zearalenone, <UI>Fusarium culture (containing 25mg zearalenone) or water (controls) daily for 10 days pre-mating commencing on day 7 of the cycle following oestrus synchronisation with CIDRs. Reproductive performance was markedly reduced in the ewes treated with zearalenone or the Fusarium culture, with only 9.1\% and 15.6\% of ewes yielding fertilised eggs compared to 57.6\% of the control ewes. Treatment reduced the number of ewes ovulating although displaying oestrus. Treated groups had 46\% of ewes anovular compared to 12\% in the controls. The ovulation rate for those ewes ovulating was less in the treated ewes (1.55) than the controls (1.86). Treatment with zearalenone or FusariumM culture reduced the proportion of egg- yielding ewes that had fertilised eggs (27.3\% and 55.5\%) compared to the controls (100\%). Treated ewes had a markedly longer duration of oestrus and it was evident from corpus luteum size that the oestrus-ovulation relationship had been disturbed.},
	issn = {1176-5283},
	author = {Dratch PA and Allison AJ and Williams TL and Kyle B and Wyllie JG and Littlejohn RP}
}
@conference {39990,
	title = {Observations on the effect of litter size, pregnancy nutrition and fat genotype on ewe and foetal parameters},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {46},
	year = {1986},
	month = {Jan},
	pages = {41-44},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Growth rates, carcass composition and management problems of "short scrotum" rams (made by elevating the testes to a position against the abdominal wall using rubber rings), wethers and entire male lambs were compared on a hill country property in northern Hawkes Bay. Of 3 groups of 65 Perendale lambs selected randomly at docking at about 4 weeks of age, 1 group was left entire, 1 was made short scrotum and the other was castrated. The lambs were weaned at about 10 weeks of age, separated from the main flock at about 14 weeks of age and thereafter kept as 1 flock until slaughter at 9 months of age. They were weighted every 6 weeks from 14 weeks of age. After the removal of 6 lambs from each group for detailed investigation at Massey University, the top 50 lambs from each group were slaughtered and their carcass characteristics recorded. Short scrotum rams showed management advantages over normal ram lambs. They were easier to handle, and avoided the works hygiene problem of dirty genitalia. Short scrotum rams had an overall live-weight advantage of 3kg over wether lambs. This was found not to be due to fat deposition, as short scrotum rams showed a significantly lower GR of 3.3mm, compared with normal rams (4.6mm) and wethers (6.2mm), as predicted by regression for lambs of 32kg live weight. There was no significant difference in carcass weight or dressing percentage between lambs of this live weight, although more normal rams and short scrotum rams fell into heavier grades than did the wether lambs. In detailed investigations on 6 lambs from each group, no differences were found in muscle:bone ratio or fat distribution between the groups. Short scrotum rams had very low fertility; 50 of 56 had no epididymal sperm reserves and 6 had extremely low sperm production. Most sperm from short scrotum rams were abnormal. Short scrotum rams had significantly lighter testes and epididymides than normal rams. Short scrotum rams had plasma LH levels intermediate to normal rams and wethers. Differences between entire and short scrotum rams in testosterone levels varied inconsistently},
	issn = {1176-5283},
	author = {Owens JL and Kyle B and Fennessy PF}
}
