However, ewes that conceive, but do not carry their lambs to term, will lose little in wool production. Although mothering ability is heritable, it's something that is largely learnt through experience. Ewes on their first lamb, regardless of age, are generally poorer mothers, and a significant proportion of lamb losses that occur after birth can usually be attributed to this. Panama disease tropical race 4 confirmed in Far North Queensland. Check if you're registered as a biosecurity entity.
Fall armyworm detected in Queensland. General enquiries 13 25 Home Industries Farms, fishing and forestry Agriculture Livestock Sheep and goats Sheep breeding and genetics Managing ewes for successful sheep breeding Choosing the right age to breed maiden ewes. Sheep breeding and genetics. Managing rams for successful sheep breeding Managing ewes for successful sheep breeding Ewe joining and breeding cycle Choosing the right age to breed maiden ewes Using the ram effect to promote ewe fertility Causes of lamb loss Reducing udder damage in ewes Joining rams and ewes for successful sheep breeding Managing replacement rams Understanding sheep genetics Improving sheep flocks through genetics Sheep health and welfare Moving sheep.
Choosing the right age to breed maiden ewes Determining the optimum age for first breeding maiden ewes isn't always straightforward - there will be gains in some areas and losses in others.
Lamb numbers In a well-managed breeding program, the average ewe is joined 5 times, first at about 1. Ewe lambs require extra nutrition because they are still growing. They will not compete well at the feed bunk with mature ewes and will not gain weight properly.
Ewe lambs that are forced to run with the ewe flock will lose weight in late gestation and lactation. Single-births are common with ewes lambs, but twins and triplets are not uncommon with the more prolific breeds.
Even when management and nutrition are proper, more lambing problems will be encountered with ewes lambing for the first time at 12 to 14 months of age. While breeding ewe lambs increases their lifetime productivity, it may not be economically advantageous for all producers. Intensively managed sheep operations usually benefit from breeding ewe lambs.
Minimum weight to breed ewe lambs. They contain progestagens that are effective at lower doses than natural progesterone. Intravaginal sponges are usually inserted over periods of 9 to 19 days and are used in conjunction with PMSG, injected at the time of sponge removal or 48 hours prior to sponge removal. Responses to intravaginal sponges have varied according to breed, protocol, co-treatment, management, and mating system.
Implantation periods range from 9 to 14 days. Estrus responses to MGA feeding vary, but are usually higher with co-treatment. Prostaglandin Prostaglandin-based protocols are only applicable to cycling ewes and are restricted to use during the breeding season.
Prostaglandins cause regression of the CL, telling the body than no pregnancy exists. The ewe will ovulate within a very predictable time. When a single treatment of prostaglandin is given to a flock of cycling ewes, 60 to 70 percent of the flock will exhibit a synchronized estrus beginning 30 to 48 hours later.
A double injection system 11 days apart is most common in sheep. Melatonin Melatonin treatments have been shown to be an effective method of inducing estrus in non-cycling ewes. Melatonin is called the "hormone of darkness," because it is released by the pineal gland during the night. Treatment with melatonin therefore mimics the short days of fall and induces estrus after a minimum of approximately 35 days of treatment.
It is important to note that most of the pharmacological treatments described above have been approved by the U. Food and Drug Administration for use in sheep, though they may be available to producers in other countries. Light Control Controlled lighting can be used to initiate estrus. Short-day breeders like sheep may be programmed to cycle if they are maintained in a light-tight building where the photoperiod is reduced gradually over an 8 to 12 week period.
Rams should be exposed to the same light regiment to obtain high fertility. Light control is usually impractical for most producers. The "ram effect" The "ram effect" is when non-cycling ewes are stimulated to ovulate by the sudden introduction of an intact male or "teaser" vasectomized ram. Rams produce a chemical substance called a pheromone, the smell of which stimulates the onset of estrus. When ewes and rams are in constant contact sight or smell , the pheromones are much less effective at inducing estrus.
Ewes that are not cycling when a ram or teaser is introduced will genrally ovulate in 3 to 4 days. This first ovulation will be a "silent" heat, which cannot be detected by the ram. Following this silent heat, there will be two normal estrus peaks, with some ewes cycling around day 18 and the remainder around day Ewes that do not conceive at either of these times may return to heat in another 17 days. It is expected that 60 to 70 percent of the ewes will conceive at the first normal estrus.
Of the remaining ewes, 60 to 70 percent should conceive at the second estrus. Although recommendations vary, rams should be isolated from ewes for at least 6 weeks in order for the ram effect to work.
Ewes must have no contact with rams by either sight or smell, which means that they must be separated by distance. The ram effect is not as effective with ewe lambs. The ram effect is most effective during the transitional period when ewes have not begun to cycle, but are almost ready to. Breed of ram can affect ewes' response to the ram effect, with the less-seasonal breeds being more effective at bringing non-cycling ewes into estrus. There are also differences among ewes, in their response to the ram effect.
The greatest value of the ram effect is the synchronization of estrus activity which will result in large numbers of ewes ovulating, conceiving, and lambing in a relatively short period of time.
To be effective, it is important to have adequate numbers of young, healthy rams. Teaser vasectomized rams or testosterone-treated wethers can also stimulate the ram effect.
Selection Selection is another method to obtain early lambing flocks, but it requires a long term commitment. Heritability is generally thought to be less than 10 percent.
Artificial insemination AI Artificial insemination is possible in sheep, but not common in the United States. This is because the ewe has a very complicated cervix which makes trans-cervical A. As compared to other livestock, the ewe shows few visible signs of heat estrus. Breed improvement in the sheep industry has been much slower to develop and the industry lacks a means to identify superior genetics.
There are four methods of artificially inseminating a ewe: vaginal, cervical, trans-cervical, and intrauternine. Vaginal AI Vaginal is the simplest form of insemination and involves depositing fresh semen into the anterior vagina without any attempt to locate the cervix. Reported success rates are highly variable and this method is unsuitable for use with frozen semen. Cervical AI Cervical is another cheap and relatively easy method of insemination.
The cervix is located, via a speculum fitted with a light source, and the semen is deposited into the first fold of the cervix. Conception rates with fresh or chilled semen are good, but generally unacceptably low with frozen, thawed semen.
Trans-cervical AI The trans-cervical method of insemination involves grasping the cervix and retracting it into the vagina with a pair of forceps to allow an inseminating instrument to be introduced into the cervical canal. Her lambs are not small by any means and her milk supply is always more than enough for her twins so i personally have never had to supplement any of her lambs. Hope my little 2 cent worth helped in some way..
As Westermans has hinted at Otherwise you suddenly find that you've got a flock of very old sheep, and no young ones coming on. Managing rams to avoid in-breeding is rather difficult though. Rotating Rams now there is the next problem for her to deal with Sign up for my monthly newsletter! Get all the latest news along with practical tips and expert advice. Calculators Vet talks Expert advice Ebooks Fun stuff.
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