Sick cria management: the Tennessee method (Proceedings)

Dealing with a sick cria and an anxious client can be quite daunting at times. This task becomes less daunting when one understands the main problems and how to manage them. Neonatal crias are typically admitted to the UT College of veterinary medicine due to prematurity/weakness/inability to stand, suspected or real failure of passive transfer (FPT), and septicemia. The condition of these crias, upon admittance, various from bright and alert to comatose.

The normal cria/overly concerned owner

Crias that are bright and alert should be evaluated for congenital defects (e.g. cleft palate, heart murmurs, choanal atresia, etc) and signs of systemic disease. Crias will normally be standing by 1 hour of birth and will nurse by 2-4 hours. Each suckling episode may last no longer than 30 seconds and may occur up to 4 times per hour. Suckling times much longer than 30 seconds and constant attempts to suckle suggest that the dam may have insufficient milk. Blood should be obtained for a total protein (TP), sodium sulfite precipitation test (SSPT) and pack cell volume (PCV). The TP and SSPT are not as specific as IgG levels but are quick and practical means of assessing FPT. If the TP is > 5.0 (some use 6 mg/dl; I personally like 5.5) or the SPT is positive (precipitation) and the PCV is not > 40, the cria is probably in good shape. However to be absolutely sure about the success or failure of passive transfer, we may also submit a serum sample for IgG levels by radial immunodiffusion (RID), which takes 24 hour for test results. The dam should be evaluated for milk production and if milk is available the cria is probably good to go. Alpaca and llama dams do not tend to have large udders and sometimes the first parturition females are slow to come into their milk. Domperidone has been recommended but there are no known scientific studies documenting the efficacy of this product. There are anecdotal reports of this product being effective but the effect may just be coincidental with naturally occurring postpartum milk production. We do use domperidone at 4 times the equine dose and anecdotally some believe it works well. If there is still question as to whether the cria is nursing successfully, it and its dam may be kept overnight for observation. It is important to accurately weigh the cria on the day of admittance and then reweigh the cria the following day to ensure weight gain. Healthy neonatal crias tend to gain around 0.5-1 lb per/day. Crias may lose weight the first day (up to 0.5 lb)....weight loss greater than this would be concerning especially in the hospital setting but maybe not the farm setting. Fowler notes that the neonate is not likely to gain weight during the first 3 days of life and may lose up to 1 lb (Fowler, 1998).

The FPT cria

Colostrum may still be absorbed systemically if the cria is less than 24 hours old. However, the closer to the 24 hour period, the less likely that colostrum will be absorbed adequately. Thus, plasma transfusion should be considered for those cases. The success of colostrum ingestion can be evaluated 18-24 hours after the first feeding. However, Weaver and coworkers concluded that the best time to evaluate passive transfer status by IgG levels is at 36 hours post-birth (2000). If camelid colostrum is not available and insufficient colostrum is available from the dam, then goat or cow colostrum is preferred. The cria should receive ~10-20% of its body weight in colostrum divided into 4-8 oz amounts with the majority ingested by 12 hours of birth. The colostrum should be administered via suckling from a bottle if possible. If the cria won't suckle, a nasogastric tube should be passed to the level of the distal esophagus to facilitate passage of the colostrum to the 3rd compartment (C3). If the cria does have a low TP, then a plasma transfusion is highly recommended. Although at greater risk, healthy appearing crias with FPT can survive and do fine (Weaver et al., 2000). Commercial llama plasma is available in 300 ml units (Triple J Farms). A jugular catheter is recommended for the transfusion. Jugular catheters are easy to place in crias because their skin is still quite thin as opposed to the adults in which because of the thickness of the skin it is sometimes difficult to see the jugular rise. However, sometimes catheter placement in crias can be challenging because of their thin and tortuous neck and because camelids in general they seem to have more prominent jugular valves. Hereby, we often place over-the wire catheter when we know they are going to need an IV access for days (we do place a short term IV catheter when they come just for plasma administration). The plasma should be administered at 15-25 ml/kg slowly IV over the first 10-15 minutes to ensure no adverse reactions and then can be administered more rapidly over the next 2-3 hours. Reactions are quite rare. We like to keep the dam and cria overnight and recheck the TP/PCV and IgG levels the next day. Usually 1 unit of plasma is sufficient and providing that the cria is gaining weight and nursing, it can be discharged. However, we find that crias have a very variable IgG increase after plasma administration. We prefer an IgG level > 1000 mg/dl; this is not always obtained and thus may utilize another unit of plasma. In a recent unpublished UT study, IgG levels were measured before plasma administration, after 1 unit and after 2 units. As might be expected, 2 units of plasma provided a greater percentage of satisfactory IgG levels (>800-1000 mg/dl) but even 2 units resulted in IgG levels < 800 mg/dl indicating the substantial variability seen when plasma is administered. Based on these results, we recommend 2 units ($150/unit). For the most accurate interpretation of weight gain or loss, it should take place at the same time every day. As a precaution (maybe without really being necessary), we will often place the cria on a systemic antibiotic (usually ceftiofur HCl) and IV Omeprazole (1mg/kg). I don't believe we've seen a neonatal cria with gastric ulceration problems but ulcers are occasionally seen at necropsy. FPT crias can certainly become septic.

The premature cria

Premature crias may be able to rise but are often weak and tend to lie in lateral recumbency rather than sternal. Their ears are usually flipped over at the tips. Their incisors may not be erupted. Many are described as having a soft and silky hair coat. They may or may not have good suckle reflexes but are almost always FPT. Colostrum may not be absorbed well in the premature cria even though it nurses or is tubed with normally adequate amounts of colostrum within the first 12 hours of life. Premature llama crias usually have birth weights < 15 lbs (average birth weight in the 20s; normal range 18-35 lbs). The premature alpaca cria usually weights < 8-12 lbs (average birth weight ~ 15-16 lbs; normal range 12-20 lbs). As long as they are not septic, the prognosis is still good but it may be 2 weeks before the cria is able to be discharged. The premature cria has some difficulty maintaining normal body temperature (100-102°F). A properly positioned heat lamp will greater facilitate temperature control but any form of heating or cooling management should be followed with rectal temperature monitoring of the neonate. The premature cria is almost always hypoglycemic and an initial glucose bolus (20 mg/kg) may be administered IV. Because premature crias also tend to have premature lungs, some are placed on oxygen (100% @ 5 l/min) for the first few days. We recently lost a premature cria that had been improving over the course of 2 days but then developed acute respiratory distress. Necropsy revealed extensive areas of atelectic lungs. Anecdotal evidence (Whitehead, 2009) suggests that administration of aminophylline at 2 mg/kg subcutaneously every 4 hours for 24 hours, then every 6 hours for the next 24 hours, then every 8 hours for the next 24 hours helps prevent the severe respiratory dyspnea that may occur with premature cria lungs. It is important to keep the dam with the cria (often separated by a see through panel). Many of these premature crias will not suckle adequate amounts of milk and must be tube fed. We usually suture a rubber catheter feeding tube (8 French 110 cm) via the nose to allow easy feeding. The nasogastric tube should extend from the external nare to just inside the thoracic inlet. It is thought that feeding in this area will help facilitate transport of the milk/colostrum to C3 instead of C1. The tube should be measured and marked prior to placement. An orogastric tube may be inserted at each feeding but a properly place and sutured nasogastric tube eliminates the need to conduct this procedure with every 2 hour feeding. When passing either tube, it is important that the head and neck not be extended which increases the chance of the tube entering the trachea instead of the esophagus. Rather, the head and neck should be a more normal position. The tube should be seen or felt on the left side of the neck during passage. A few milliliters of water should be passed in the tube initially if there is any question as to its correct placement. We usually try to feed 10% (ranges from 5-15%) of the body weight daily via the feeding tube (feeding every 2 hours over the first few days then increasing the amount and decreasing the number of feedings) but attempt bottle feeding as the cria gets stronger. Eight to 10% of body weight is thought to be the requirement for maintenance with an additional 5-8% required for growth. All tube feeding should be by gravity flow to decrease the chance of regurgitation which could result in aspiration pneumonia. We usually start with 5 % of the cria body weight, and then we slowly increase the percentage by 2% per day. When the dam's milk is not available, we use goat milk replacer and use 1 part replacer to 6 parts water. The glucose is monitored during this time as hyperglycemia has occasionally been a problem. Camelids easily develop hyperglycemia which is believed to be due to insulin resistance. In crias, one of the biggest concerns is their risk of developing hyperosmolar syndrome (discussed below). When this happens, we back off of the feedings a bit and if this doesn't lower the glucose we may consider insulin. As time goes on and the cria begins to suckle the bottle well, we allow the cria to attempt to suckle the dam. The suckling instinct must be very strong as all that have survived eventually maintain themselves via nursing the dam and some have gone for > 2 weeks without nursing. We do our best to milk the dams and cessation of milk production in the dams has not yet been a problem. We monitor the weight (any weight gain is considered positive and helps us determine when the cria is nursing enough off the dam so that hand feeding can be discontinued) and glucose of the crias at least once daily.

The septic cria

Major blood work is not really required for the uncomplicated FPT cases or normal cria unless some abnormalities have developed. But for the septic cria both a CBC and chemistry panel are easily justifiable. Many things can and do go wrong with the neonatal camelids. Initial management includes placement of an over the wire IV catheter. Fluid therapy can begin with normal saline until electrolyte abnormalities are known. It is relatively easy to overhydrate a cria and create life-threatening pulmonary edema so exercise caution with fluid rates. We start with 40 ml/kg/24hr. Glucose should be administered depending on glucose levels and insulin may be needed as well. The action point for glucose varies from one source to the next but if > 300 or < 70 action is needed (unfortunately the urinary glucose threshold has not been investigated). Bactericidal antibiotics are preferred. We typically use potassium penicillin (44,000 IU/kg QID IV) and ceftiofur HCl (4.4 mg/kg) or amikacin (21 mg/kg IV; extrapolated from neonatal foal dose).

Miscellaneous Conditions

Meconium impaction: Meconium is normally passed within 18-20 hours of birth. It is certainly possible that the passage of meconium could be missed but as long as the cria is acting normally, this should not be reason for alarm. The actual incidence of this condition is not known but it is a differential for straining in the neonate. A couple of warm water soapy enemas usually do the trick. Occasionally an owner will over-do-it on the enemas and this in itself creates the straining. Thus, if the cria is passing manure, repeat enemas are not necessary.

Hyperosmolar syndrome (HOS): The history may include dystocia, sepsis, or any condition that might result in decreased milk intake. Signs suggestive of HOS include lethargy, anorexia, hyperthermia, tremors, seizures and if standing a wide-based stance. Although numerous biochemical abnormalities may be identified, the syndrome primarily centers around hypernatremia and hyperglycemia. The hyperglycemia may be the initiating factor and is thought due to endogenous release of glucocorticoids released during stressful events. The hypernatremia is thought to occur due to glucosuria which results in an osmotic diuresis resulting in sodium retention and body water loss. The excess sodium is thought to affect the cerebrum resulting in the neurologic signs. While the hypernatremia may be corrected by treatment with Na dilute fluids, the hyperglycemia may need to be corrected first and usually requires insulin treatment (Buchheit et al., 2010). As they are hyperglycemic (have seen up to 1000 mg/dl), they develop glucosuria, accompanied by water; consequently, the cria gets dehydrated. With the dehydration, they become hypernatremic, which overall increases the osmolarity of the blood. Clinical signs include lethargy, tremors, and neurologic signs. For this reason, in hyperglycemia and/or hypernatremic crias, we perform regular blood work (with the I-stat machine) to measure their sodium, potassium, glucose and BUN in order to calculate the osmolarity. The normal osmolarity if 300-310 mOsm; clinical signs of hyperosmolar syndrome can start to be seen when the blood osmolarity reaches 350 or 360 mOsm. When hyperosmolar syndrome is a concern, we dilute the IV fluids: usually we start with ¾ regular fluids (plasmalyte, Norm-R) mixed with ¼ sterile water; sometimes we use a 0.5:0.5 ratio. We monitor the blood osmolarity (every 6 or 12 h) and observe for neurological signs.

References

1. Buchheit TM, Sommardahl CS, Frank N, Roberson JR. Use of a constant rate infusion of insulin for the treatment of hyperglycemic, hypernatremic, hyperosmolar syndrome in an alpaca cria. J Am Vet Med Assoc 2010, 236:562-566.

2. Fowler ME. Neonatology. In 2nd Edition Medicine and Surgery of South American Camelids, editor ME Fowler, Iowa State Press, 1998, pg. 452-467.

3. Triple J Farms Llama Plasma, 777 Jorgensen Place, Bellingham, WA 98226.

4. Weaver DM, Tyler JW, Scott MA, et al. Passive transfer of colostral immunoglobulin G in neonatal llamas and alpacas. Am J Vet Res 2000, 61:738-741

5. Whitehead C. Management of neonatal llamas and alpacas. Vet Clin North Am: Food Animal 2009, 25:353-366.