Language – EN – Date 21/09/2018
Welcome to the fourth SheepNet newsletter for 2018 – with some news about the project activities and upcoming events!
First SheepNet briefing papers available in 6 languages
SheepNet has produced its first factsheets to help deliver solutions to questions relating to sheep productivity. These are three briefing papers, which describe the background to the three main topics of SheepNet: efficient reproduction, efficient gestation and lamb survival. The purpose of these factsheets is to describe the current state of knowledge on these three areas, and to help to facilitate discussions within local, and national networks to share solutions. The factsheets have been translated into the 6 languages of SheepNet, and can be downloaded from the Knowledge Reservoir on the SheepNet website (www.sheepnet.network/knowledge-reservoir).
Photo: Kasia Maslowska
Improving reproductive efficiency
This factsheet outlines how reproduction efficiency can be measured (the fertility rate and the prolificacy of the flock). The worldwide acceptable rate of fertility is around 90% pregnancy of ewes exposed to a ram, whereas prolificacy depends very much on the sheep breed, varying from 1 to 4 lambs per ewe lambing. However, reproduction efficiency can vary widely, with fertility rates lower than 70% and prolificacy equal to 1 lamb per ewe lambing. The improvement of these parameters is possible, with the best flocks reaching 95-100% fertility rate and litter sizes up to 3-4 in prolific meat breeds. To optimize the reproductive efficiency of a flock it is fundamental to consider the management of the flock during the reproduction cycle, according to the genetic potential of the breed. The SheepNet factsheet explains the management factors that can contribute to poor fertility and how these might be addressed. Each farm or flock may have different risk factors and prevalence for different causes of low fertility. Identifying the main reasons for fertility failure and the more important risk factors are the key steps in developing mitigation strategies. Recording fertility data and identifying when and why sheep do not lamb will help to improve reproduction efficiency.
Improving gestation efficiency
Gestation efficiency in sheep is defined as the proportion of ewes known to have conceived that give birth to viable lamb(s). Average fertilization rate is around 90-95%, however, not all embryos and fetuses will survive until full term. Abortions (termination of a pregnancy after day 30) can occur at any stage of pregnancy. The SheepNet briefing paper on this subject outlines the main causes of foetal lamb losses and suggests possible approaches to minimise these. Identifying the main reasons for abortion and the more important risk factors are the key steps in developing mitigation strategies. Recording whether ewes have bred (e.g. raddle marks), ultrasonography dates/results and abortion data, in order to identify when and why sheep do not lamb, will help to improve gestation efficiency.
Improving lamb survival
The average lamb mortality from scanning (mid-pregnancy) until weaning or sale is between 15-25%. However, between-flock variation exists, ranging from 3% to nearly 50% mortality. Lamb mortality is highest on the day of birth, and nearly half of all deaths occur within the first week of life, but the risk of dying remains higher for lambs than for adult sheep throughout early development. The main risk factors for lamb mortality are ewe undernutrition causing light lambs and less milk; larger litter sizes as smaller lambs from multiple births are more vulnerable to starvation and exposure; maternal inexperience and genetic factors, stress or disturbance at lambing and the lambing environment. Many of the causes of lamb mortality are preventable. A key goal should be for all lambs to suckle adequate amounts of colostrum from the ewe as soon as possible after birth. This will ensure a good bond between ewe and lamb, prevent starvation and hypothermia, and protect the lamb from some causes of infectious disease as gut closure will occur more quickly.
Following the success of Spanish transnational workshop (see our June newsletter), the next transnational workshop will be held in Sardinia, Italy (Alghero), on 28-29 November 2018. These 2 days will be a great opportunity to discover Italian sheep production and to share ideas and solutions on best practices, including the use of technology to help sheep management. Go to the website to register your interest (www.sheepnet.network/news) as soon as possible, to make sure you can book a place.
Photo: Marianne Farish
SheepNet is open to all EU countries, stakeholders, sheep producers. For further information: