The effect of breeding ewe lambs on subsequent two-year-old ewe performance

Kenyon, P. R.; Proctor, L.; Morel, P. C. H.; Morris, S. T.; West, D.M.

doi:10.1016/j.livsci.2007.07.008

Cited by 21 publications

(25 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In comparison with many earlier studies, it is important to note that, in this work, ewes that had lambed as a hogget were not given preferential feeding (Kenyon et al 2008). Preferential feeding could have limited the ability of the study to identify potential negative consequences of ewe hogget breeding.…”

Section: Discussionmentioning

confidence: 95%

“…However, Dyrmundsson (1973) stated that breeding at a young age in wellmanaged and nourished ewes has no detrimental effects on subsequent reproductive efficiency and, in some studies, has enhanced subsequent fertility leading to an increase in lifetime performance. More recently, Kenyon et al (2008) managed pregnant and non-pregnant ewe hoggets as one group and reported that ewe hogget breeding reduced two-tooth live weight, body condition score and reproductive performance. Under these conditions, it may be hypothesised that breeding ewe hoggets would have a negative effect on ewe lifetime productive performance.…”

Section: Introductionmentioning

confidence: 99%

“…54, No. 4, December 2011, 321Á330 present study was to record the performance of the two-tooth ewes in the study of Kenyon et al (2008) during the subsequent 3 years to determine if breeding as a ewe hogget impacted on lifetime performance.…”

Section: Introductionmentioning

confidence: 99%

“…As previously described by Kenyon et al (2008), to determine the effect of hogget breeding on two-tooth performance, ewe hoggets (n 01163; 8Á9 months of age) were randomly divided into two groups in May 2004 and were either presented for breeding with rams for a 34-day period (n0873) or not bred (n 0290). At the end of the breeding period, all ewe hoggets were merged into one group and managed under commercial grazing conditions until those that were diagnosed pregnant were grazed separately for lambing and lactation during the period from late September 2004 until mid-January 2005.…”

Section: Introductionmentioning

confidence: 99%

“…those that were presented for breeding and lambed (mated and lambed, MP) 2. those that were presented for breeding but did not become pregnant (mated and not lambed, MNP) 3. those that were not presented for breeding (not mated, NM Kenyon et al (2008).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The effect of breeding hoggets on lifetime performance

Kenyon

Linden

West

et al. 2011

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

The reported study involved mature ewes that had either been presented for breeding and had lambed as a hogget (MP), had been presented for breeding as a hogget but did not become pregnant (MNP) or were not presented for breeding as a hogget (NM). Their subsequent performance as mature ewes was examined. Although breeding as a hogget reduced (P B 0.05) two-tooth mating live weight and condition score in subsequent years, the differences were either smaller or not present at all (P !0.05). Breeding as a hogget increased (PB0.05) the number of foetuses per ewe lifetime (8.290.08, 7.090.13 and 7.190.12 for MP, MNP and NM respectively) but did not alter ewe (P!0.05) longevity. These results indicate that hogget breeding can be used as a management option to improve lifetime reproductive performance.Keywords: ewe lamb; hogget; breeding; reproduction; lifetime performance IntroductionIn New Zealand, approximately 30% of ewe lambs (7Á9 months of age; hoggets) are presented for breeding each year, but these ewe hoggets wean less than 4% of total lambs weaned in the national flock (MAF, 2010). These results indicate that increasing the percentage of ewe hoggets successfully bred and that rear a lamb to weaning is a means of increasing the national flock's productivity. A number of potential advantages of breeding ewe hoggets have been identified. These include higher net profits, improved utilisation of spring herbage, increased efficiency, early recognition of fertility potential, improved fertility level throughout the flock, increased rates of genetic gain and improved lifetime production of the ewe by breeding her at a younger age (Hight 1982;Kenyon et al. 2004b). However, Kenyon et al. (2004a) reported that the main reason farmers do not breed ewe hoggets is a perceived negative effect on breeding performance at 18Á19 months of age (twotooth). A negative effect on two-tooth performance may negate any potential positive effect of successful breeding as a hogget on lifetime performance. However, Dyrmundsson (1973) stated that breeding at a young age in wellmanaged and nourished ewes has no detrimental effects on subsequent reproductive efficiency and, in some studies, has enhanced subsequent fertility leading to an increase in lifetime performance. More recently, Kenyon et al. (2008) managed pregnant and non-pregnant ewe hoggets as one group and reported that ewe hogget breeding reduced two-tooth live weight, body condition score and reproductive performance. Under these conditions, it may be hypothesised that breeding ewe hoggets would have a negative effect on ewe lifetime productive performance. Therefore, the aim of the *Corresponding author.

show abstract

Section: Discussionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations