@conference {3672,
	title = {BRIEF COMMUNICATION: Does Viagra protect fetal lambs against maternal pregnancy toxaemia?},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {76},
	year = {2016},
	month = {07/2016},
	pages = {172-174},
	address = {Adelaide},
	abstract = {Poor fetal growth is commonly caused by placental
insufficiency. In sheep, multiple fetuses have relatively small
placentae with fewer cotyledons than singletons, limiting
blood flow to the placenta, especially in late gestation
when fetal growth rate is highest. Factors that reduce fetal
growth, such as maternal genotype, nutrition, age, parity,
fetal number, or environmental temperature, typically
reduce placental size and are associated with lower rates
of fetal oxygen and nutrient uptakes and placental blood
flow (Reynolds \& Redmer 2001). Further, circumstances
that influence placental vascular development have a
dramatic impact on fetal growth and development, and
affect neonatal survival and growth (Borowicz et al. 2007;
Satterfield et al, 2010).
Sildenafil citrate (SC, trade names Viagra or Avigra)
increases vasodilatation of uteroplacental vessels (Wareing
et al. 2005) and may represent a novel therapy to improve
fetal lamb growth. Sildenafil citrate has successfully
increased birth weight in rodent models and singleton bearing
ewes (Satterfield et al. 2010; Miller at al. 2009).
There is no published information regarding the use of SC
in multiple-bearing ewes. The objective of this trial was to
determine if SC administration to triplet-bearing ewes in
late gestation could increase lamb birth weight. In addition,
the influence of SC on the incidence of pregnancy toxaemia
is also reported here.},
	issn = {1176-5283},
	author = {Peterson SW and Pain SJ and McCoard SA and Oliver M and Baker PN and Kenyon PR and Blair HT}
}
