@conference {42029,
	title = {Inheritance of chondrodysplasia in Texel sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {68},
	year = {2008},
	month = {Jan},
	pages = {20-22},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Brisbane, Australia},
	abstract = {A skeletal chondrodysplasia (noncancerous abnormal cell growth affecting cartilaginous tissues) characterized by dwarfism and angular deformity of the forelimbs has been recognized in Texel and Texel cross lambs. Some affected lambs have normal co-twins indicating the disease is likely to be of genetic origin. This study outlines the mode of inheritance of the disorder. Three affected rams were mated to 221 unaffected ewes to generate 123 daughters, which were backcrossed by multiple sire mating with their sires the subsequent season to produce 83 lambs for evaluation. The time course of the morphological progression of the disease was recorded. Of the 46 lambs that were successfully diagnosed, 22 were affected with the condition and 24 were unaffected. This was consistent with a 50:50 ratio expected for recessive inheritance in a backcross between affected and carrier animals. Within sexes, 11 males (24\%) and 11 females (24\%) were affected with 10 males (22\%) and 14 females (30\%) were unaffected. This was not different (P<0.05) from a 0.25 proportion for autosomal recessive inheritance. Variation in the age of onset (16 days {\textpm} 7 days) and severity of clinical expression suggests variable penetrance, with semi-lethality. },
	issn = {1176-5283},
	author = {Byrne TJ and Blair HT and Thompson KG and Stowell KM and Piripi S}
}
@conference {41369,
	title = {Subclinical Johne{\textquoteright}s Disease in Sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {62},
	year = {2002},
	month = {Jan},
	pages = {284-287},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {<p>This paper presents preliminary results from a 5-year study aimed at generating objective data on the effect of subclinical Johne{\textquoteleft}s disease on productivity in sheep. On two properties where Johne{\textquoteleft}s disease was considered to be a problem, replacement ewe lambs from a single generation were allocated to one of three groups. One group was vaccinated with the killed Mycobacterium avium subsp. paratuberculosis vaccine Neoparasec, another with the live vaccine Gudair, and the other group remained as unvaccinated controls. The vaccinated and control ewes were monitored over the ensuing four years for the following parameters: lesion size, live weight, fleece weight, scanning percentage, lamb production and weight of lambs weaned per ewe. Serology was also performed on a sample of animals from each group. On one property, the size vaccination-site lesions associated with Gudair declined at a more rapid rate than those associated with Neoparasec. However, results to date have failed to detect a significant difference in productivity between vaccinated and unvaccinated ewes in either flock, suggesting that subclinical Johne{\textquoteleft}s disease may not be an important cause of production loss in sheep. The trial is now in its final year.</p>},
	issn = {1176-5283},
	author = {Thompson KG and West DM and Anderson PVA and Burnham DL}
}
