Effect of partial replacement of barley with molassed sugar beet feed in concentrate given and winter shearing on the performance of pregnant ewes and survival of new-born lambs

Egan, E.; Notman, A.B.; Hill, João Ari Gualberto

doi:10.1017/s1752756200596227

Proc. Br.Soc. Anim. Sci.

1997

DOI: 10.1017/s1752756200596227

|View full text |Cite

Effect of partial replacement of barley with molassed sugar beet feed in concentrate given and winter shearing on the performance of pregnant ewes and survival of new-born lambs

E. Egan¹,

A.B. Notman

João Ari Gualberto Hill

Abstract: Winter shearing of ewes has been shown to reduce the incidence of hypoglycaemia in twin bearing ewes (Symonds et al, 1986), increase litter birthweight and reduce lamb mortality especially in housed conditions (Austin. 1982. Vipond et al, 1987). It is however not clear if winter shearing effects lamb birth weight independently of nutrient intake or reflects solely an increase in the intake of nutrients in late pregnancy. The aim of the experiment was to study the interaction between changing the source of ener… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2002

2003

Publication Types

Select...

Article2

Relationship

Self Cite0

Independent2

Authors

Journals

Cited by 2 publications

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

Shearing ewes at mid-pregnancy is associated with changes in fetal growth and development

Revell¹,

St²,

Cottam³

et al. 2002

Aust. J. Agric. Res.

View full text Add to dashboard Cite

This study investigated the effect of mid-pregnancy shearing (at Day 70 of pregnancy, P70) on herbage intake of grazing single- and twin-bearing ewes, lamb birth weight, and cold resistance of new-born lambs. At pregnancy diagnosis on P50, 30 single-bearing and 30 twin-bearing ewes were allocated either to be shorn at P70 (n = 15 for each pregnancy rank) or to remain unshorn to serve as controls (n = 15 for each pregnancy rank). All ewes were mated over a 3-day period with synchronisation of their oestrus. Herbage intake was measured indirectly from in vitro pasture digestibility and faecal output of grazing ewes, with the use of intra-ruminal chromium slow-release capsules, over six 5-day periods from P64 to P105. The weights of placental and fetal tissues were assessed in a subgroup of 16 ewes at P140 and P141. In the remaining sheep, lamb liveweight at birth and during lactation until weaning at 103 days of age was measured, and cold-resistance of new-born lambs was assessed by measuring summit metabolic rate (SMR) by indirect calorimetry. Ewe liveweight (corrected for fleece weight), condition score, and herbage intake during pregnancy were not affected by shearing treatment. Mid-pregnancy shearing did not affect placental weight, but increased the relative weights (i.e. g/kg liveweight) of fetal thyroid gland and lungs and reduced the relative weight of adrenal glands and heart. The ratio of secondary to primary wool follicles in near-term fetal skin was about 10% higher in offspring of shorn than of unshorn ewes. The metabolic rate of fetal hepatic tissue was increased by mid-pregnancy shearing, particularly in twin fetuses, possibly indicative of an increase in placental transport of nutrients to the fetuses. This conclusion is supported by the greater birth weight (average response 0.5 kg) of lambs born to ewes shorn at mid-pregnancy. Mid-pregnancy shearing also increased the SMR of new-born twin lambs by 16%, but decreased the SMR of singleton lambs by 26%. These results indicate that mid-pregnancy shearing can increase lamb birth weight without increasing ewe herbage intake or placental weight. An increase in the efficiency of nutrient uptake by the placenta is implied, and possible effects on the activity of thermogenic tissues are discussed.

show abstract

Shearing ewes at mid-pregnancy is associated with changes in fetal growth and development

Revell¹,

St²,

Cottam³

et al. 2002

Aust. J. Agric. Res.

View full text Add to dashboard Cite

show abstract

Shearing during pregnancy — review of a policy to increase birthweight and survival of lambs in New Zealand pastoral farming systems

Kenyon¹,

St²,

Revell

et al. 2003

New Zealand Veterinary Journal

View full text Add to dashboard Cite

Over the past decade, lambing percentages have risen in conjunction with a rise in the percentage of multiple lambs born. Multiple-born lambs are smaller than their singleton counterparts and are particularly susceptible to starvation-exposure. Any technique that can increase the birthweight or thermoregulatory capability, or both, of otherwise lightweight lambs has the potential to substantially increase survival of multiple-born lambs. In the United Kingdom under housed conditions, shearing during pregnancy has been shown to increase both the birthweight and thermoregulatory capability of newborn lambs. However, shearing during pregnancy under pastoral conditions has failed to consistently affect the newborn lamb's thermoregulatory capability. In contrast, under New Zealand's pastoral conditions shearing during pregnancy has been found to increase birthweight, but results have been inconsistent in both magnitude and birth-rank specificity. Increase in feed intake by the dam, types of shearing comb used and changes in gestation length do not explain the variation observed. When studies involving shearing during pregnancy are collated it becomes apparent that there are two criteria that must be met to achieve a birthweight response. Firstly, the dam must have the potential to respond and secondly, the dam must have the means to respond. Any increase in lamb survival through shearing during pregnancy would be predominantly through an increase in birthweight of otherwise lightweight lambs. However, in the few studies conducted to date, an increase in birthweight has not resulted in a statistically significant increase in survival. For an increase in birthweight to have a positive effect on lamb survival, lambs must be otherwise destined to be born within a birthweight range in which survival rate is below optimum (<4.0 kg), and the increase in birthweight observed must move a significant proportion of otherwise lightweight lambs into a higher range of survival rate.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Effect of partial replacement of barley with molassed sugar beet feed in concentrate given and winter shearing on the performance of pregnant ewes and survival of new-born lambs

Cited by 2 publications

References 1 publication

Shearing ewes at mid-pregnancy is associated with changes in fetal growth and development

Shearing ewes at mid-pregnancy is associated with changes in fetal growth and development

Shearing during pregnancy — review of a policy to increase birthweight and survival of lambs in New Zealand pastoral farming systems

Contact Info

Product

Resources

About