The profitability of a sheep enterprise depends on the number of lambs sold either for meat or as breeding stock. The number raised to market is a reflection of the complete management of the flock throughout the year. One of the critical points in this management cycle is lambing.
The ewe is required to deliver strong healthy lambs and to have sufficient milk to raise those lambs. Her ability to do this is a reflection of the gestation management. After breeding a ewe should body score 2.5.
Throughout much of the gestation period a diet of good hay should suffice. In the last six weeks, grain can be fed in addition to hay to allow for the growing lambs, the development of the udder, and the fat reserves of the ewe for lactation. The amount of supplementary feed depends on the size and body condition of the ewes and the quality of forage being fed. At lambing the body score should be between 3 and 3.5. Care must be taken not to feed too much grain early in gestation, gradually increasing the amount allows for lamb development. A leveling out or fall in late pregnancy grain intake can result in pregnancy toxaemia and death of the lamb(s) in utero. Conversely, too little grain will give an undersized, weak lamb with a poor chance of survival. Also, the ewe will have insufficient udder development for a good lactation.
Not less than four weeks before the due date of the first ewe, all the ewes should receive a booster vaccination against the clostridial group of diseases, (all first lamb ewes should have completed the primary vaccination course before breeding) and an injection of Vitamin E/selenium. If they are not to be sheared, they should at least be crutched to remove excess wool from the udder area.
Each ewe should have a lambing pen in which the bonding between ewe and lamb can be monitored, the lamb is easily caught for any procedures (tail docking etc.), and is seen to be nursing. Depending on the system used, the ewe can be put into this pen when lambing is observed to be imminent, or after the lamb has been dropped. The pen should be about 1.5 m square with a corner divided off to give the lamb a safe area from the ewe. Once the lamb is vigorous and all treatments completed, it and the ewe can be let out into a larger pen with other ewe/lamb sets. After each ewe, the soiled bedding is removed and fresh bedding put down. On average, expect each ewe to spend three days in this pen.
To be prepared for lambing you will need two kits. One to assist the ewe at lambing (see Assisting the Ewe at Lambing) and the other to process each lamb as it is born.
Lamb Processing Kit
This kit (see Figure 1) should contain:
- suitable syringe and needles
- iodine solution for dipping navels
- Vitamin E/selenium injection
- ear tags and applicators and/or tattooing pliers
- tail docking rings or cutter
The average gestation period for a ewe is 147 days, but some will always be early. Have the kit of lambing aids ready in advance. The lamb should start breathing at birth. It may need help; check that there is no placenta covering the nostrils or mouth. A gentle rub over the chest with a towel or straw wisk, tickling the inside of the nostrils with a piece of straw or blowing into the nostrils (do not allow your lips to come in contact with the wet lamb while doing this) will often stimulate breathing. There is also a commercial device1 for this task.
TINT Your Lambs
In the first few days of a lambs life there are several procedures that should be carried out. Once you are certain that the lamb has had adequate colostrum, TINT them.
T = Tails
I = Inject
N = Navels
T = Testicles
The tails need to be docked before the lamb is seven days old (Code of Practice for Sheep). The tail can be removed with:
- electric or gas heated docker
- rubber ring
- crush and cut device
- rubber ring plus crushing device.
The docked tail should cover the anus of the ram or the vulva of the ewe. A good guide is to remove it at the joint in the tail bones just beyond the web on the underside of the tail.
In Ontario, newborn lambs can be born selenium deficient. As a routine, they should be injected with the appropriate dose of a Vitamin E/selenium preparation. Read the label on the bottle for the route of injection, either subcutaneous or intramuscular. Always inject into the neck area, never into the muscles of the hind quarters. (Note: If the ewe has been given supplements during pregnancy this may not be necessary)
The navel of the newborn lamb needs to be disinfected as soon after birth as possible. The untreated navel is an excellent route for infectious agents to enter the lamb causing internal abscessation or joint ill. An iodine solution is the most common disinfectant used. It is either sprayed onto the navel or the navel is dipped in a small container of the solution. If dipping the navels, replace the disinfectant solution in the container after every tenth lamb.
If the market lambs are to kept beyond three months of age, they need to be castrated. Again, whether rubber rings, crushing or cut and pull is used, this should be done before seven days of age (Code of Practice for Sheep).
Whether tattoos, ear tags, or ear notching is used, the lamb must be identified before it leaves the lambing pen.
For any one of a variety of reasons, a lamb may need to be fostered onto another ewe. If possible fostering should be considered as an option before bottle feeding for the orphan. Fostering should be as soon after birth as possible. If the lamb has not dried off, so much the better. If fostering from a set of triplets, choose the strongest lamb. Keep the ewe and the fostered lamb in a lambing pen until you are certain that the adoption has succeeded.
To persuade the ewe to accept the lamb, one of several techniques can be used. Rub the lamb in the placenta of the ewe’s own lamb; if you are replacing a dead lamb, put its skin onto the adoptee; if the ewe still refuses, she can be put into a head gate to prevent her pushing the lamb away when it attempts to suckle. After a few days in the headgate, the ewe will usually accept the lamb.
Author: Dr. S. John Martin, BVM&S, MRCVS, Veterinary Scientist, Sheep, Goat and Swine
This article is one of a set: “Assisting the Ewe at Lambing” and “Care of the Newborn Lamb”, concerning lamb survival. They should be read together.