Claire E Whitehead
When Neonatal Crias Get Sick?.?
Claire E Whitehead BVM&S MS FHEA MRCVS
Diplomate ACVIM (Large Animal)
Camelid Veterinary Services
In 1998, there was an article written in the Veterinary Record regarding population statistics and mortality rates in South American Camelids in the UK (Vet Rec 1998;142(7):162-6). This article discussed the findings of a postal questionnaire that had been sent to owners. The highest mortality rates (17-33% of total alpaca deaths) were found in animals aged less than 6 months with the highest proportion of those occurring in the first week of life. Yesterday I ran a Neonatal Clinic for owners and reported these statistics: we all hoped that this situation had improved due to increasing knowledge and better education? Perhaps it?s time for another survey to find out? However, I still have many communications with owners who tell me about a cria that died at 3 or 4 days old and they didn?t know why? This concerns me. There is always a reason for that cria to have died and in most cases it should be fairly obvious on veterinary clinical examination or post-mortem examination.
There are 4 main reasons for a neonatal cria to be struggling (a neonate is a cria that is less than 2 weeks of age):
2.) Hypoglycaemia (low blood sugar)
3.) Failure of passive transfer of immunity (FPT) leading onto sepsis
4.) A defect that the cria has been born with (eg heart defect).
Any combination of these problems is also possible. The good thing is that these problems are pretty easy to diagnose. There are also some less serious ones such as meconium impaction but these will not be discussed here.
You can easily check whether a cria is hypothermic by checking its rectal body temperature. Normal temperature should be 38-38.9C, less than this and the cria is hypothermic. You can rectify this situation by warming the cria. Bring the cria indoors and warm it up using blankets, heat lamps, heat mats, hot water bottles etc. Latex gloves filled with warm water work quite well and can be placed under the back legs to help warm the large blood vessels passing through there. If you place any warm items next to the cria be careful to cover it with a cloth or towel so that it doesn?t scald the skin. Never use a warm water bath as this just draws the blood supply to the skin away from the core and this may cause cardiovascular collapse.
Hypoglycaemia is most common in newborns that have failed to suckle. They are born with a normal blood glucose level but they need to suckle milk from their dams in order to maintain blood sugar. If they don?t nurse, blood sugar levels fall off and they?ll subsequently collapse. If you find a collapsed cria, first check its body temperature and warm up if necessary. Secondly, smear a little sugary solution inside the mouth of the cria from where it will be readily absorbed and may be lifesaving while awaiting a visit from the vet. You can use anything that is concentrated sugar such as syrup or runny honey. This should not do any harm. Slightly older crias may have normal, high or low blood sugar and there is likely something else going on as well?
FPT and Septicaemia
Ensuring adequate colostrum intake is vital in order to protect newborn crias from infections during the first few months of life (this is called passive immunity). There is only a narrow window of opportunity: after about 8 hours of life, the gut will start to lose its ability to absorb antibodies from the colostrum and after 24 hours, virtually nothing will be absorbed. Failure to ensure colostrum intake may result in failure of passive transfer of immunity (FPT) and, unless this is addressed, may result in potentially fatal infections.
If you are unsure whether a cria has taken in enough colostrum, perhaps because it didn?t get going early enough, or because you are concerned about the mother?s milk availability or it may be exhibiting signs of prematurity, you can check for FPT in one of several ways. The first couple of methods involve measurement of total protein or globulins in the blood ? your vet should easily be able to do this for you. However, total protein measurement is heavily dependent on hydration status (globulin not so much) so may not be as useful in a sick cria where other tests may be more useful such as evaluation of a blood smear and chemistry tests. There is also a camelid-specific immunoglobulin (IgG) test available that measures adequacy of passive transfer, but this takes 12-24 hours to run so is not so useful in an emergency situation if the cria is already showing signs of illness. It is great for screening for FPT though. The only place currently offering this test commercially in the UK is Camelid Veterinary Services. An alternative IgG test has become available in recent years and has potential since the results are available more readily.
If the cria fails to gain weight or actually loses weight, this can be an early sign that something is wrong, most likely that the cria has FPT and is developing septicaemia (where bacteria enter the bloodstream and start to produce toxins that result in organ failure). However, there may be other reasons for this (eg defects) and the cria should be evaluated by your vet.
Once FPT has been diagnosed, the only way to remedy the situation is by plasma transfusion since the cria can no longer absorb antibodies out of the intestines, along with antibiotic and supportive therapy where necessary if sepsis is developing. Plasma (usually 150-300ml volume) should be given intravenously through an IV catheter and results in very few complications when proper aseptic preparations are made and the transfusion is given slowly (usually 20-40 minutes). The intravenous catheter may also be used to administer antibiotics and further fluids if necessary if the cria has already become sick. Intraperitoneal transfusion has been advocated by some but is not recommended by this author ? it is an archaic standard of medicine to practice and can have many more complications than transfusions given intravenously: it can not only be painful resulting in loss of appetite and growth, but may cause potentially fatal problems such as peritonitis and adhesions between loops of intestines.
There are a number of defects that can cause crias to be failing in the first week or so of life: examples appear below. These problems should be identified as early as possible by veterinary examination: the ones that cause clinical signs of illness are often not correctable and these crias should be euthanased on welfare grounds. Those that are easily correctable should be identified and treated early before secondary complications develop: bear in mind that these animals should never be bred from.
? Heart Defects. Crias suffer from a number of heart defects, the most common of which is a Ventricular Septal Defect (or ?hole in the heart?). These defects do not always cause clinical signs but when they do, we have a limited ability to deal with these problems medically. If a defect is suspected by your vet on the basis of listening with a stethoscope, this should be evaluated by use of an echocardiogram (cardiac ultrasound) performed by a cardiologist who will be able to diagnose the problem ? this is important for making breeding decisions later. Not all heart murmurs (abnormal sounds) are due to defects: generally, the louder ones are. Quieter ones may also be due to illness ? dehydration, electrolyte disturbances and sepsis can all result in murmurs and need to be differentiated from those caused by defects?
? Choanal Atresia. This causes respiratory difficulty. The defect is caused by a failure of the back of the nostrils to open during embryologic development such that a membranous or sometimes bony defect prevents air from passing through the nostrils ? in short, they cannot breathe normally and have to mouth-breathe. Some crias compensate for this relatively well while the majority show respiratory difficulty fairly shortly after birth. Often crias will puff out cheeks while breathing and may struggle to nurse because they get out of breath. Making the diagnosis is fairly simple: a red rubber catheter or other soft-ended tube should be passed up the nostril ? there will be a blockage at the level of the eye. Surgery is possible but the prognosis is not great since most affected crias already have FPT and sepsis by the time of diagnosis and hypoxaemia (low blood oxygen concentrations) causes them to be further compromised. In addition, other defects are often present in crias with this defect. Surgery should only be considered in animals that are stable clinically. Otherwise, they should be euthanased.
? Imperforate Vulva. The cria strains to urinate. The vulva pouches out below the anus and appears to be fluid-filled: this develops as urine builds up behind the vulva since the cria cannot pee. Therefore it is not obvious at birth unless you look carefully at the vulva. This is an easy problem to correct by the vet by making an incision in the midline to make a normal sized vulva opening (local anaesthetic gel can be used to anaesthetise the area ? sedation is not necessary). No suturing is required.
? Anal Atresia. These crias have no anus and therefore cannot pass faeces. As long as the defect only affects the anus, your vet can correct this problem surgically.
What can you do to identify problems early and give your cria the best chance at life?
Appropriate management in the first few weeks of a cria?s life is essential to ensure that it makes it through the high risk neonatal period, grows well and survives into adulthood. Fortunately there are some really basic and easy things that you can do.
1.) Ensure adequate colostrum intake in the first 24 hours (see separate box)
2.) Weigh newborn crias on the day of birth. Alpaca crias normally weigh an average of 7.5kg. If they weigh less than 7kg, they may be more at risk of not getting sufficient colostrum and warrant closer observation.
3.) Weigh crias daily for the first 2 weeks of life. During the first 24 hours, crias may lose weight as they dry off and pass their meconium (first faeces). After the first 24 hours, they should consistently gain weight at the rate of 0.25-0.5kg daily. This reflects adequate intake of milk. If they fail to gain weight, or lose weight, this is the very first indication that something is not right and the cria may have FPT. Action at this point, including diagnostics and possible plasma administration, rather than waiting until the cria collapses, will result in the best outcome for your cria and the least impact on your finances in terms of veterinary care.
4.) Screen crias for FPT. You may choose to do this for all crias, or just those of high risk (including low birth weight, known difficulties nursing or getting going) or high potential value. This decision is up to you. Screening allows early identification of FPT: if found, plasma transfusions can prevent further illness from developing and reduce subsequent costs.
5.) Do not delay seeking veterinary attention for any sick crias. If your vet doesn?t know much about alpacas specifically, suggest that they call me for advice and help.
Notes on Plasma
There is currently no commercial source of plasma in the UK. There is a commercial plasma bank in the US but plasma would need to remain frozen in transit and pass by customs quickly! Permissions would also have to be checked before placing any orders! In the UK, your vet can collect blood from donor alpacas in your herd and process into plasma for you to store for an anticipated clinical need. Vets cannot legally sell plasma without a license from the Veterinary Medicines Directorate ? this is a license to run a blood bank essentially. There are many quality control steps that have to be taken in order to earn the license (which also carries a hefty annual fee) but this is in order to maintain quality of the product and safety for the intended use.
How do you ?make plasma?? Ideally this should be organised prior to the start of the birthing season. Basically, the vet has to place an IV catheter in a suitable adult donor animal for collection to take place. Donors should ideally be males over 3 years old, preferably vaccinated every 3-4 months or 3 weeks prior to collection in order to ensure good antibody levels. Castrated males make perfect donors. Blood is collected into 450ml bags and a special (large) centrifuge is required to centrifuge the blood (in the bags) and separate off the plasma into separate sterile packs that are stored in the freezer until use. Very few vets have their own centrifuges as they are quite large and can be expensive ? they are not the regular centrifuges that they will use on a day to day basis. However, blood can be sent by courier to the Pet Blood Bank at Loughborough: it will be processed there and sent back by overnight courier frozen. Blood needs to be centrifuged as soon as possible after collection (and kept cool or ideally refrigerated in the meantime). Plasma is best used within a year of collection: after this it starts to deteriorate.
Over the last few years, I have heard of a number of suboptimal practices from various sources. It is essential that blood and plasma products are collected, stored and administered in a sterile manner. If this is not done correctly, administration of these products could be potentially very detrimental to the recipient. Examples include aspiration of collected blood into small blood tubes for spinning, followed by separation of plasma into other containers such as bags; and storage of plasma in syringes which is completely inappropriate as it cannot remain sterile.
How should plasma be given? The most effective means for administration of plasma to crias is by intravenous infusion. Administration of plasma by intraperitoneal (IP) infusion is about 1/3 less effective and leads to many more potential complications observed by this author following referral for these complications, particularly if either the site of injection or the plasma is not 100% sterile. Additionally, if the cria is already starting to develop sepsis, an adverse reaction to IP plasma is more likely. I have also heard of owners recommending plasma to be given by mouth to crias. It is important to bear in mind that colostrum is massively more concentrated in antibodies (among other important components) than plasma: since antibodies from either will only be absorbed in the first 24 hours, when colostrum is available in the mother?s milk, there seems to be little point wasting space in the cria?s stomach with an inferior product that is far more costly to produce when colostrum is on tap nearby? The cria only has 24 hours to take on board that colostrum so it is pointless to make life harder for it. If you are going to go to all the effort of collecting blood and making plasma, use that valuable product wisely and give it directly into the bloodstream where it needs to get to and where it will have the optimum effect.
If you or your vet have any questions about plasma supply or administration, or would like to consult on any sick crias, I would be delighted to hear from you. I am available for consultation on 01707 666297, or by email: firstname.lastname@example.org
What is colostrum?
Colostrum is the first milk produced by the mother: among other goodies, it contains the all-important antibodies from the mother to protect the newborn cria from infections. Unlike humans, crias are born without antibodies and need this protection before they start making their own.
How can you ensure adequate colostrum intake?
If a cria is not particularly active soon after birth and is not getting up to nurse within the first 4 hours, it is likely that the cria will need assistance. Initially this can just be making sure that the cria gets up to nurse frequently, or help with getting the cria into the right place to nurse and making sure it latches onto a teat. Otherwise, bottle-feeding with the dam?s own colostrum or stored colostrum will be necessary.
If a dam has insufficient milk, then frozen camelid colostrum can be used, or goat, cow or sheep colostrum as alternatives ? goat is best since it is the closest to camelid milk in composition, but cow is usually easier to acquire. If acquiring colostrum from elsewhere, always make sure that it is from a BVD, Johnes and TB free herd. Colostrum can be either fresh or frozen. Frozen colostrum keeps for up to 1 year in the freezer and is best stored in 75-100ml portions. [NB Don?t microwave-thaw!!] Avoid powdered colostrum supplements which are not designed to be substitutes for colostrum. These really only provide energy. Aim to feed 10-15% of the cria?s bodyweight over 24 hours, divided into feedings every 2-4 hours. Preferably feed by bottle, though tube-feeding may be necessary initially. If you have to tube-feed more than twice, there is probably a reason why the cria is not getting up and nursing for itself and you should seek veterinary attention.