Winter weight management for young livestock
The management of weaners, particularly ewe and heifer weaners, is often neglected in dry seasons, having profound implications on future reproductive performance. Leading into winter, producers should follow correct weight management practice, to reduce mortality odds and improve the productive potential of sheep.
In trial work done at Trangie research institute there was a significant reduction in net reproductive rate in ewes that did not achieve benchmark weight for age as weaners.
Lee et al 2009. Taken from AWI Winning With Weaners.
This data demonstrates that a 1.5 kg weight differential at 10 months of age resulted in up to 4 less lambs being raised during the ewe’s reproductive life. The same principals apply to cattle. As well as having lasting effects on net reproductive rate, poor growth rates during puberty has been shown to stifle skeletal development. Compromised skeletal development will predispose breeding females to:
- An increased incidence of dystocia (calving and lambing difficulties) due to poor pelvic development – less live offspring and higher vet bills.
- An increased incidence of uterine prolapse resulting from imperfect pelvic development.
- Reduced calcium reserves. The skeleton is the principal repository for calcium, a mineral of utmost importance during parturition and lactation.
Inadequate nutrition during in the first 10 months of any mammal’s life will also impact muscle development which has obvious implications for growth rates and carcass weight.
The only sure way to manage weaners is to weigh regularly (at least monthly) and ensure that they are achieving adequate weight gain – in ewe weaners at least 75g/hd/day and heifers at least 0.5 kg/day.
The smaller the animal the less feed is required to achieve reasonable growth rates, so the tip is to be proactive. The following strategies can be employed:
- Wean when lambs reach 40% or calves reach 30% of standard reference weight. Standard reference weight will vary according to breed and genotype. Calculating the standard reference weight is an important step in determining weaning weighs and target weights.
- Draft weaners into mobs determined by weight – heavy, medium and light.
- Feed a high-quality diet customised according to weight. This ration should be balanced for energy, protein and fibre and include the full suite of macro and microminerals and vitamins.
- Ensure a good supply of clean, fresh, cool water. Trough water is preferred over dam water and troughs should be cleaned at least daily.
- Administer the appropriate animal health treatments. Weaning is a stressful period in the animal’s life. Stress impacts growth and immune system, rendering the animal susceptible to secondary infection such as respiratory disease and coccidiosis. Removing or mitigating the effects of stress through the treatment of diseases and parasites reduces the stress load on the animal.
For more information on weaner management, including strategies to reduce the stress of weaning, yard weaning and early weaning, consult your Elders Livestock Production Advisor or visit your local branch.
Elders End of Financial Year Catalogue is now live offering savings on key animal health products, including weight management tools, supplements and troughs. Click here to view the catalogue and contact your local branch for further information.