A planned approach at tupping time

Date published: 12 September 2019

Rams

It is vital to check rams feet, testicles, condition score and general health at least eight weeks prior to breeding.

Timely intervention is essential as it takes 6-8 weeks for spermatology to occur. The quality of semen produced from a ram today will reflect the condition the ram was in approximately seven weeks ago. Similarly it is important to purchase rams early to allow them as long as possible on your farm before mating begins. This will help to minimise the risk of any stress occurred, such as at a sale or through change of diet, affecting the subsequent fertility of the ram.

Rams should be in good condition (BCS 3.5 – 4) going out to ewes. Supplementation with meal prior to breeding can aid this and can also help improve semen quality. For quiet rams getting them used to meal can provide a convenient and stress free method of catching them while out with ewes to change his raddle. Testicles should be even, firm and of normal size (at least 32cm circumference for ram lambs and 34cm for older rams).

Ewes

For ewes, monitoring and managing body condition score (BCS) is the key element to a successful conception rate. The traditional tried and tested way is to have ewes on a slightly lower than average BCS (2.5 for hill or 3 – 3.5 for lowland ewes).Then by flushing these ewes aim to increase ovulation rate and build BCS. However recent research has suggested that alternative method of keeping ewes in constant slightly higher BCS (3 for hill ewes and 3.5 – 4 for lowland) and not flushing the ewes can work just as well. The advantages of this is that it is slightly easier to manage and having ewes in good BCS provides a reserve of body condition which can be mobilised in later pregnancy and during lactation if needed.

Whichever way BCS is managed it is vital that a constant level of nutrition is maintained and stress kept to a minimum from tupping through to early pregnancy. Implantation in the uterus occurs approximately 15 days after fertilisation. Any change in diet, BCS or stress can lead to embryo mortality and a poor scanning rate. After fertilisation occurs the placenta develops and although the ewe’s nutritional requirements do not increase in early pregnancy it is still important to maintain a level plain of nutrition to allow continual foetal growth and even distribution of the cotyledons on the placenta (i.e. avoid one big lamb and one small lamb developing).

Vaccinations

Timely vaccinations pre tupping are also an important step to ensure a successful lambing and maximise lambs produced per ewe. Even if abortions seem like they are not an issue, if ewe’s are lambing down with weak lambs, or with less lambs than initially scanned for or if scanning rate is lower than anticipated then an underlying disease issue may be a problem. Depending on the stage of pregnancy the ewe is infected, Toxoplasmosis can lead to stillbirths, foetal death, or weak lambs which can die soon after birth. Enzootic abortion will most commonly lead to abortion in the last few weeks of pregnancy however similar to toxoplasmosis it can occasionally lead to weak, premature lambs or still births.

Vaccines for toxoplasmosis and enzootic abortion must be administered at least three weeks and four weeks prior to tupping respectively.

Summary

Analysis of CAFRE benchmarking data continually shows that lambs produced per ewe is the most important factor affecting output and profitability of sheep enterprises. Whilst flock prolificacy is influenced by several factors, such as genetics and stage of breeding season, management of the flock prior to and during the breeding season is a major factor affecting performance and hence profitability of the enterprise for the following year.