Amesbury Animal Hospital

277 Elm Street
Amesbury, MA 01913

(978)388-3636

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Basics of Small Ruminant Reproduction

Part Two

By Beth A. Pelletier, DVM

            Welcome back small ruminant fans!  This month I am going to cover the birthing process and neonatal lamb and kid care, as promised.  Refer to February's Dr. G's corner for part one of this series.   

            Let's pick up again where we left off: the expectant does and ewes are in a clean, dry place approaching their 5th month of gestation.  They have had their CDT vaccine updated within the past 3-4 weeks and you are monitoring them more closely for signs of parturition.  You should also deworm your pregnant females 3-4 weeks prior to parturition to prevent heavy shedding of parasite eggs around the newborns. 

            Parturition (labor) occurs in 3 stages.  Stage 1 is the beginning of uterine contractions.  The doe or ewe may show mild signs of restlessness or pawing.  This can last 1-10 hours in the doe, 2-6 hours in the ewe.  Stage 2 is delivery with active pushing and possibly vocalizing.  The doe should deliver all kids within 3 hours, and each should take less than 1 hour.  The ewe should deliver within 2 hours.  Active labor lasting any longer than the above times indicates dystocia (difficult birth).  Stage 3 is elimination of the placenta.  Does and ewes usually pass the placenta within 1-12 hours after birth.   

            The normal position of a kid or lamb during delivery is front legs first, then the head resting on top of the legs, followed by the rest of the body.  Also acceptable is hind feet first but also upright (refer to drawings).  Any other position has the potential for difficulty.  For example, presenting tail first with the hind feet forward is a breech presentation.  Some kids or lambs, if they are small enough, can be delivered in a breech position.  If the ewe or doe is having difficulty (see timing above) you can attempt to palpate the kid or lamb and reposition it (or call your veterinarian).  Thoroughly wash your hands and forearms as well as the mother's vulva with disinfecting soap.  Gently place a lubricated hand into the vagina to feel the position of the kid/lamb.  If you feel a tail, try to push the body forward into the uterus to allow the hind feet to come towards the cervix.  If you can grab a hoof, cover it with your hand (to prevent it from scraping the uterine wall) and pull the leg out toward the vagina gently but firmly.  Repeat this with the other foot until a normal position is obtained.

               Caution with does!  The most common form of dystocia in does is more than one kid at the birth canal.  If you feel 2 legs, make sure they are from the same kid!  If not, you will have to try to push one kid back and pull the other one forward.  If the head is tucked under, push back and try to lift the chin.  Make sure the front legs are forward, as described for the back legs above.  To assess whether you are feeling front legs or back legs, feel the joints: the first 2 joints on the front legs bend in the same direction.  The first 2 joints on the back legs bend in opposite directions (see drawings).  Identifying which legs you have tells you whether to expect a head!  If you should feel the head but you don't, it must be tucked down, back or to one side and the nose needs to be brought up towards the cervix. When in doubt, don't! Call your veterinarian.  The sooner you call for assistance during a difficult birth the greater the likelihood of a positive outcome for mom and baby.

           If you can't get your hand between the mother's pelvic wall and the kid/lamb body part, it may be too large to pass vaginally and your veterinarian should be called.  This may require a cesarean section.  Try to identify the kid/lamb's head and put a finger into its mouth, the natural reaction to this is suckling.  If you don't feel the kid/lamb suckle it may be dead.  If it is not breathing once it is delivered (but it has a suckle reflex) try slapping its sides and removing any mucous membranes inside its nose or mouth with a bulb syringe or towel.  This sounds silly, but rapidly twirling around 3-4 times holding the hind legs of the baby helps to remove fluids from the airway.  Alternatively, you can simply hold the baby upside down to help the fluids drain out.  If the umbilicus is still attached, gently rip it (do not cut!) several inches away from the body wall of the baby.  Dip the umbilicus in 7% iodine or betadine to protect it from infection.  This can be done with a Q-tip/cotton ball or by dipping the umbilicus into a small container of the disinfectant.  Note: Don't touch the iodine, it can burn and stain your skin!

            The most critical time for bonding between the kid/lamb and the mother is the first 12 hours.  If the baby is taken away for more than 6-12 hours it may be rejected by the mother.  The kid/lamb should be standing within 30 minutes after birth and colostrum (first milk) must be consumed within the first 24 hours of life.  Colostrum is thick, yellowish milk produced during parturition.  It is rich in energy, protein, vitamins, minerals and most importantly, maternal antibodies (stimulated by that CDT vaccine you gave during the last trimester of pregnancy).  

            Antibodies protect the baby from disease causing viruses and bacteria during the first weeks of life.  You can make sure the mother is producing colostrum by stripping each teat after parturition.  This will help remove the wax plug making it easier for the babies to suckle and allows you to evaluate for a strong stream of colostrum.  If the mother has been leaking milk prior to parturition, or if she is not producing an adequate amount (more likely if she has more than two offspring) you should feed the kids or lambs with colostrum via a nippled bottle or stomach tube.  This can also be done if the lamb or kid is too weak to nurse.  Ewes and does that have extra colostrum can be milked out and the colostrum frozen (up to 12 months) for later use.  The best source for supplementation is fresh colostrum from the kid or lambs own mother or another female in the herd or flock who has recently given birth.  If frozen colostrum is needed, it must be thawed slowly in a warm water bath in order to preserve the antibodies.  Colostrum should be fed at body temperature (102-103F, 39-40C), 2-4 ounces at a time, every 3-4 hours.  Within the first 24 hours after birth, kids and lambs should receive 10% of their weight in colostrum.  In other words, a 10 pound lamb should receive 16 ounces of colostrum.  

            Commercial colostrum can be acquired.  It is important to differentiate between colostrum 'supplements' and colostrum 'replacers' or 'substitutes'.  Supplements do not contain adequate antibodies to be used as a sole source of colostrum.  However, colostrum labeled as a replacer or substitute is able to raise blood antibody levels above a certain critical level.  Milk replacer should not be fed until the lamb or kid has received adequate colostrum.  

            To further help their immune systems, young should be vaccinated with CDT at 8 weeks old and one month later.  If their mothers had not been vaccinated prior to parturition (shame, shame) the young should be vaccinated sooner, at 2-6 weeks old and boostered one month later. 

            A picture of an Disbudding and tail docking (of lambs), should be performed within 2-7 days, depending on the breed and gender of the animal.  We recommend disbudding larger breeds and bucks at 2-3 days of age.  Docking should be done distal to the tail folds so the tail covers the anus and vulva.  This can be performed by placing a specialized rubber band around the tail using an 'elastrator' (see pictures on left), or with burdizzos, a tool that crushes the tail (the silver tool in picture on right).  A The similar tool to burdizzos, the emasculator has a cutting edge as well as a crushing edge so removing the tail is a one step process (make sure the cutting side is placed away from the body!).  If burdizzos are used for docking, a scalpel is needed to cut the tail off below the crush.  Many veterinarians will use a local anesthetic at the site of tail docking and will also suture the end of the tail.  

           A disbudding iron on left and burdizzo on right. Disbudding prevents the growth of horns.  An electric disbudding iron (see picture on right) is placed over the horn buds for 10-20 seconds at a time, until a copper ring is visible.  This destroys the horn cells.  Caution! It is possible to destroy brain cells if left on too long!  As usual when in doubt, don't.  Call your veterinarian.  Improper disbudding results in 'scurs', abnormal, usually twisted and stunted horns that grow from a few remaining horn cells. 

            The decision as to when to castrate kids and lambs depends on their purpose: meat or pets.  Meat animals should be castrated at the time of disbudding or tail docking.  Male lambs and kids intended for pets should not be castrated until 3 months of age.  This helps prevent urethral obstructions (see article, 'Goat Urinary Obstruction' from February 2010 under Dr. G's Health Corner).  Castration can be performed using burdizzos to crush the vessels supplying the testicles.  It is important to stay between the abdominal wall and the testicles and to crush both sets of vessels in an alternating pattern so that blood supply to the scrotum is not compromised.  Scrotal necrosis (death) can occur if this is done improperly.  This technique is a bit tricky so I do recommend having a personal demonstration by an experienced professional before you perform this task yourself.  (I also prefer to use a small amount of a sedative/pain medication, but this is not absolutely necessary).   

            Congratulations!  You have completed your crash course in small ruminant reproduction.  With a little experience, skill, and common sense, you too can raise adorable little kids and lambs.  There are, certainly, other reproduction related issues you should be aware of, but they are beyond the scope of this article.  I have listed some topics below so you can investigate them through other sources:

            Abortion

Infectious Causes: Chlamydia, Campylobacter, Toxoplasmosis, Q Fever,    Leptospirosis, Listeriosis, Brucella melitensis, Salmonella, Mycoplasma/Ureaplasma 

Non-infectious Causes:  Drugs, Chemicals, Poisonous plants  (including phenothiazines, dewormers, locoweed, lupine, veratrum)

            Pregnancy Toxemia

            Nutrition

            Vaginal Prolapse

            Ringwomb

            Congenital Defects

            Uterine Prolapse (rare)

            Retained Placenta (if >12 hours)

            Metritis

            Uterine Tear

            Uterine Abscess

            Freemartinism

            Ovarian or Uterine Tumors

            Hydrometra

            Caprine Herpes Virus

            Mastitis

Glossary: 

Ruminant - one of the order of animals, including cattle, sheep, goats, deer, and antelopes, which have a stomach with four complete cavities (rumen, reticulum, omasum, abomasum), through which the food passes in digestion.

Small ruminant -includes sheep and goats

Goat terms

            Doe - adult female

            Buck - adult male

            Wether - castrated male

            Kid - young goat

            Kidding - birthing

Sheep terms

            Ewe - adult female

            Ram - adult male

            Wether - castrated male

            Lamb - young sheep

            Lambing - birthing

Parturition - birthing process

Dystocia - difficult or abnormal birth

Estrus - the state of sexual excitability when the female of most mammals is receptive to the male and capable of conceiving, aka 'heat'

Diestrus - a period of sexual quiescence that intervenes between two periods of estrus

Anestrus - An interval of sexual inactivity between two periods of estrus in female mammals that breed cyclically