Thursday, June 19, 2014

Moniezia - The Milk Worm

Moniezia is the only adult tapeworm of any interest in sheep. Not because of any damage it causes, but rather because it is somewhat obvious and shepherds tend to worry about it, probably unnecessarily. The adult tapeworms live in the small intestine of young lambs during the summer months of April, May, June, and July; particularly when lambs are grazing but still nursing. They may grow to a length of 4 to 5 meters and also lambs may be infected with several tapeworms at the same time. Segments may be very obvious in the faces. Ribbons of segments may occasionally be seen twirling in the breeze as lambs run behind their mothers. However, despite the fact that at slaughter it may be possible to collect literally a bucketful of these from the guts of only two or three heavily parasitism lambs, they apparently do little harm. Moniezia does not parasite older resistant sheep and generally live for only a few months in lambs. A number of anthelmintics which are used routinely for the control of parasitic gastro-enteritis, such as Albendazole, Fenbendazole, and Oxfendazole, are also effective against Moniezia tapeworm. If lambs are grazing, they will need to be dosed for Nematodirus and if an appropriate wormer is used, it will control both parasites simultaneously.

Tuesday, February 25, 2014

                                                            Birth Trauma 
When delivering lambs, please always remember how fragile lambs are and how easily they may be damaged. A large number of lambs are injured during the birth process, as is demonstrated by detailed post-mortem examination. Even lambs born naturally, without any human intervention what so ever, may be injured by the crushing pressures bearing down on them during the birth process. Any additional force applied by hand will increase the risk of injury very significantly. 
   Returning lambs from the birth canal to the uterus and correcting any abnormal posture is most easily done when ewe is not straining. Up ending the ewe is helpful, since her pressing is less effective in this position. When pulling on the lamb, it is best to wait for the Ewe to strain unless she has given up. Aim to withdraw the lamb with a smooth, rather than a jerk action. The ewe may be laid down on her side when actually delivering the lamb, so that her own contractions will assist with the birth. 
   The delicate tissues of the uterus and birth canal must always be protected from the hooves of the lamb by cupping the feet in the palm of the hand when manipulating them. The lamb's teeth can occasionally cause damage especially when the head is roped, as this tends to open the mouth. Some lambs, such as Awassi dairy sheep, are born with sizable horn buds, which can cause considerable damage especially if they are born backwards. It is also taken for granted that strict hygiene will be taken, that lubricants will be used liberally and that every ewe will be given antibiotic treatment following any interference. 
 When a ewe has been examined and the lamb is found to be alive and presented normally, the birth canal is fully relaxed or in the process of opening up and the ewe is correct in every other way, then she should be left to lamb in her own good time. Frequent observations, not internal examinations, will show whether she is making progress. Further interference will only be necessary if no progress has been made after 1 to 2 hours. 


Thursday, January 16, 2014

Improving the Response to Vaccination

In order to get an optimal response to vaccination- especially with dead vaccines- other components are added to the antigen to increase the immune system. These substances are known as adjuvants, are more or less irritant to the body tissue, so that quite often a lump will appear at the site of the inoculation. With some vaccines, the reaction will be hardly noticeable, but with others, a large- unsightly swelling will develop which may be painful. 
            In years past, all sorts of strange substances were used as adjustments, such as Tapioca, starch, or even bread crumbs. Today, substances such as aluminum hydroxide or light-mineral oils are used, but only reasonably, they are far from satisfaction. A new generation of adjuvants which stimulate a strong immunity, but don't provoke a reaction at the vaccination site are urgently required. It should be known that a lump at the inoculation site doesn't mean the vaccine has not been effective, but rather the reverse. Oily adjuvants in particular will cause a nasty reaction in humans if vaccine is accidentally inoculated into or scratched onto the skin, and medical attention should be sought immediately. 
Live vaccines, depending upon the micro organisms multiplying in the tissues, when the vaccine is introduced into the skin via a deliberate scratch made by a special applicator dipped in the vaccine, it is essential that the virus is not killed through the use of spirits, disinfectants, dips or pour ons; otherwise the vaccine will not 'take'. 
           It is very important to always read the vaccine manufacturer's instructions and to follow them strictly. Needles and syringes should be changed as instructed and empty vaccine containers disposed of safely. Never vaccinate sheep in bad weather, or when they are sick, wet, or dirty. Sick animals should be marked so that they can be done when they have fully recovered. Never mix vaccines or administer another vaccine or any other treatment at the same time, unless manufacturer or your Veterinarian advises that it is safe to do so. Particular care and caution should be taken in the case of pregnant ewes. 
*Importantly: always wear gloves for human protection while administering and handling vaccines and keep vaccines stored in proper placement via temperature storage (refrigeration, room temperature, etc.)