Border Leicester rams into action
| Project start date: | 30 October 2014 |
| Project end date: | 01 November 2016 |
| Project status: | Completed |
| Livestock species: | Sheep, Lamb |
| Relevant regions: | Southern Australia |
|
Download Report
(1.1 MB)
|
|
Summary
First cross ewe producers using Border Leicester (BL) rams have sometimes experienced low and variable lambing results when joining BL rams to Merino ewes in the spring. Seven clients from Inverbrackie stud proposed that seasonality might be an issue, so a Producer Demonstration Site (PDS) was established to examine if treatment of rams with melatonin would overcome the problem
There was indirect evidence from ram activity data collected on Producer Demostration Site (PDS) properties that melatonin may have improved libido in young rams enabling them to compete with their older counterparts. Most PDS members recognised the value of treating young BL rams with melatonin but were more reserved about using the technology in mature rams.
Commercial users of the melatonin technology in young BL rams can be reasonably confident of achieving a higher reproductive performance (all other factors being equal) as pregnancy rates in both years of the current study and in that of Kleemann et al (2014) were around 90%. The main benefit of the technology when used in young BL rams is that between year variability of pregnancy rate is reduced.
Objectives
The objectives of this project were to:
• increase the weaning rate of Merino ewes joined to Border Leicester rams in spring from an average 90% -120% by using melatonin technology
• deliver best practice information to BLxM producers to increase their knowledge skills and confidence to improve management of the breeding cycle of Merino ewes
• discuss findings from the project, undertake evaluation of PDS members’ attitudes to melatonin treatment and assess business benefits.
Progress
• Treatment of young BL rams prior to joining in November increased pregnancy rate (89% vs 82% in year 2, but not in year 1 (94% vs 93%).
• Treatment of mature BL rams did not increase either pregnancy rate or litter size.
• Libido tests indicated melatonin increased ram performance at one location but not at another.
• Melatonin treatment brought forward the distribution of pregnancies.
• Further studies are required on a larger number of ewes and rams to confirm that melatonin treatment of BL rams has an impact on litter size and whether ewes become pregnant earlier. Confirmation of these responses and reasons for them need to be established.
