Herd Health of Llamas and Alpacas

Newborn camelids stand within 15 to 45 minutes and start bonding with the dam immediately. Camelids do not lick their newborns, however. Mothers will hum to their offspring, nuzzle, and touch noses frequently. If everything appears to be progressing appropriately, the animals should not be disturbed and should be allowed to bond. Crias should be on their feet within 30 minutes and attempting to nurse within 30 minutes to 1 hour after birth. They will have short nursing periods every 1–2 hours for the first few days. Although weight gain for the first 24 hours after birth may be minimal, thereafter llamas should gain 250–500 g/day and alpacas 100–250 g/day. Healthy crias should approximately double their birth weight by 1 month of age.

Routine cria care should include weighing and single dipping the navel in dilute chlorhexidine or povidone 2 or 3 times in the first 24 hours. If appropriate for the area, supplemental selenium can be provided. Normal birth weight is 7–11 kg for an alpaca and 9–15 kg for a llama. Heart rate ranges from 60–100 beats/min, and respiratory rates average 30 breaths/min. Body temperature is usually close to 100ºF (37.8ºC). Meconium and urine are usually passed < 18 hours after birth.  See table Parameters for Newborn Llamas and Alpacas

Crias showing any evidence of dyspnea are true emergencies. Choanal atresia is the most common congenital abnormality in camelids. This condition can be unilateral or bilateral. The latter is rapidly fatal because the camelid is an obligate nasal breather. A mirror should be held under the nostrils of the neonate to look for condensation. Prognosis for repair of bilateral choanal atresia is not good. Unilaterally affected animals can survive in some cases without surgery; however, they are never normal. Affected animals should not be bred.

Prematurely born crias may have a noticeably different appearance from a normal neonate. Unusual physical characteristics of premature crias include a domed head, floppy ears, excess periople on their feet, and peculiarly silky fur. The unique fourth placental membrane of camelids, the epidermal membrane, usually very thin and unseen, may be thickened and excessive. Premature crias may fail to stand and may lack a suckle reflex, which puts them at high risk of failure of passive transfer of immunity. Many of these animals start to deteriorate shortly after birth due to consequences of perinatal hypoxia and require intensive care. Respiratory, cardiovascular, and nutritional support may be required for such crias, and sepsis is a possible complication.

Sepsis is also a risk for animals that do not receive adequate colostrum after birth. Failure of passive transfer of immunity is common in both llamas and alpacas. Newborns should ingest 10%–15% of their body weight in colostrum within 24 hours of birth, and ideally by 12 hours. Testing for passive transfer should be done at 18–24 hours. Radial immunodiffusion kits are available for llamas and alpacas; they are considered the gold standard, but obtaining results takes 24 hours. Other tests for passive transfer include refractometry of total solids, which should be >5.5 g/dL. Sodium sulfite turbidity, sodium sulfate turbidity, and γ-glutamyl transferase (GGT) measurements are not useful in camelids. Neonates experiencing failure of passive transfer of immunity will require at least one, and sometimes several, plasma transfusions.  

Blood transfusion, llama

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Courtesy of Dr. Ellen Wiedner.

Neonates should be weighed daily during the first month of life. If bottle feeding, they should continue to receive 10%–15% of their weight divided among feedings every two hours. Appropriate socialization with other animals is necessary for bottle-fed animals; hand-raised crias have a high likelihood of imprinting on and developing abnormal ways of relating to humans (eg, showing dominance or sexual behaviors) and can become dangerous and unpredictable as they mature (berserk llama syndrome).

Multiple congenital defects have been reported in crias. These include cardiac defects, musculoskeletal defects, atresia ani and coli, vulvar deformities, and others. Often, animals with one major defect will have other abnormalities that are less apparent, so it is important to be thorough in examining a newborn. The genetics of many abnormalities are unknown; however, it is unwise to rebreed the parents of neonates with congenital defects.

Parasite control programs vary according to climatic conditions, population density, and parasite load and should be developed according to local conditions. Although no drugs have been approved specifically for use in camelids, anthelmintics that are generally recognized as safe and effective include the standard classes of drugs administered to ruminants. Resistance has developed in all parasite species that affect camelids, making it necessary to develop a strategic deworming program, particularly in locations where meningeal worm (Parelaphostrongylus tenuis) is endemic. Trematodiasis caused by liver flukes (Fasciola hepatica, Fasciola gigantica, Fascioloides magna, Dicrocoelium dendriticum) can be a notable problem in wet, warm regions.

Mild sarcoptic mange, alpaca

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Courtesy of Dr. Ellen Wiedner.

Sarcoptic mange, llama

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Courtesy of Dr. LaRue Johnson.

Sarcoptic mange lesions, llama

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Courtesy of Dr. LaRue Johnson.

Horner syndrome, llama

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Courtesy of Dr. LaRue Johnson.

Gastrointestinal nematodes are an important problem in camelids due to significant resistance to multiple anthelmintics. Multiple species of nematodes that affect ruminants also affect camelids and cause similar problems. Haemonchus contortus infections, for example, can lead to severe and even fatal anemia. Whipworms (Trichuris spp) are particularly problematic, because camelids often don’t shed eggs even with severe infection, confounding diagnosis. Chronic cases and severely affected animals can appear emaciated and depressed, with poor-quality fiber and anorexia. 

As in ruminants, exclusive use of anthelmintics as a technique of parasite control is not effective and increases resistance-related issues. Parasite management in camelids requires combining thoughtful use of anthelmintics, identification and removal of heavily parasitized animals unresponsive to treatment, pasture management techniques designed to decrease loads of parasites in fields, and exploration of nontraditional, novel parasite control techniques ranging from feeding certain forms of copper, supplementation of diet with tannin-containing plants, nematode-trapping fungi, and anthelmintic vaccines. Named for South African veterinarian Dr. Faffa Malan, the FAMACHA system correlates pallor of the ocular mucous membranes, assessed using a color chart, with the degree of anemia associated with Haemonchus contortus parasite burden. More conventional parasite control recommendations include fecal flotations four times a year and fecal reduction egg count tests to identify resistance and assess anthelmintic efficacy. A reduction of 90% or more is desirable. Animals should be weighed before deworming to avoid underdosing.

Several protozoans affect camelids. Eimeria macusaniensis causes severe disease in camelids of all ages. Unique and specific to camelids, it causes nonspecific signs that include lethargy, weight loss, anorexia, and diarrhea, which rapidly progress into circulatory shock and death. Fecal flotation is often negative initially, which confounds diagnosis, but a fecal PCR assay can help. Aggressive treatment with crystalloids, colloids, supportive care, and amprolium or ponazuril are needed, but mortality and morbidity may still be very high. At necropsy, lesions and parasites are most often found in the ileum and distal jejunum. Animals may also develop hepatic lipidosis, sepsis, and third stomach compartment (C3) ulcers as sequellae. Other Eimeria species can affect camelids, and oocysts may be identified on routine fecal flotations of otherwise healthy animals.  

Cryptosporidium spp is a zoonotic, protozoal disease primarily of neonatal camelids, usually < 3 weeks old, but sometimes of older animals as well. These organisms can be infectious to other species. Although infection can be self-limiting, animals with severe diarrhea, dehydration, and metabolic derangements require treatment. Diagnosis is by fecal flotation in conjunction with acid-fast staining of fecal smears. Fluorescent antibody staining of feces can be used diagnostically as well. Aggressive fluid therapy, correction of acidemia, and parenteral nutrition may be required for severe cases along with antimicrobials, anti-inflammatories, and good nursing care. Evaluation of husbandry and cleaning procedures is recommended after Cryptosporidium outbreaks. Unfortunately, oocysts are extremely resistant to most disinfectants and can persist in the environment for years.  

Meningeal worm (Parelophostrongylus tenuis), nasal bots (Cephenemyia spp), and American deer flukes (Fascioloides magna) are risks to camelids that share pasture with wild cervids. Meningeal worm is particularly onerous, causing severe and permanent neurologic disease in camelids, which are dead-end hosts. Snails and slugs are the intermediate hosts for this parasite, and infected deer, which are not clinically affected, are primary hosts. 

Camelids become infected by eating the intermediate hosts. Once ingested by the camelid, the parasitic larvae emerge from the invertebrate host and migrate to the spinal cord and brain. An array of neurologic signs are associated with P tenuis and depend on what part of the nervous system is hosting the larvae. Treatment is rarely helpful; prevention is key. In areas where P tenuis is endemic, keeping deer out of camelid paddocks and drying up wet areas or using molluscides to prevent slug and snail infestations can be helpful. Preventative therapies include monthly ivermectin administration, but this has contributed to anthelmintic resistance. Diagnosis can be challenging, particularly early in the course of the disease, but the finding of eosinophilia in CSF in conjunction with neurologic signs is both sensitive and specific.

All four genera of mange mites (ie, Sarcoptes, Psoroptes, Chorioptes, and Demodex) have been diagnosed in camelids. Alopecia, hyperkeratosis, and scaling accompanied by pruritus can be caused by any of these. Clinical signs may resemble those of zinc deficiency. Skin biopsies are usually required to make a definitive diagnosis, and sometimes multiple samples are needed. Although various options for therapy exist, most mange cases will respond to administration of routine parenteral doses of ivermectin repeated every 10–14 days. Oral therapy does not appear to be as effective. Chorioptes infestation may require higher drug doses repeated every 14–21 days and local therapy. Refractory Sarcoptes cases involving the lower legs have benefited from the same topical treatment.

With louse infestation, it is important to determine whether pediculosis is due to biting lice (Damalinia breviceps) or sucking lice (Microthoracius cameli). This can be accomplished with the aid of a hand lens or microscope. Use of transparent tape to retrieve lice for diagnosis from within the depths of wool can be attempted. Sucking lice can be treated with injectable ivermectin as per routine mange therapy. However, biting lice are not affected by parenteral ivermectin. Topical application of synthetic pyrethrin preparations has been effective, but critical doses for these species have not been established. Preventive measures for lice and mange include routine treatment of new herd additions as well as animals visiting and returning for breeding purposes or from shows. Ticks have caused tick paralysis as is seen in other species. In addition, ticks gaining access to ears have caused inner ear afflictions resulting in Horner syndrome as well as encephalitic death.

Camelids living in wet environments appear to be particularly susceptible to the common liver fluke (Fasciola hepatica), which affects the bile ducts. Fecal shedding begins 10–12 weeks after infection. Clinical signs can include ill thrift, diminished growth, and acute death. Icterus is rare. Treatment is with clorsulon (7 mg/kg, PO, once, repeated 45 days later). Affected animals are at risk of infectious necrotic hepatitis caused by Clostridium novyi (black disease) and, if not up to date on vaccinations, should be given a multivalent clostridial toxoid vaccine.

Snake envenomation, llama

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Courtesy of Dr. LaRue Johnson.

Most vaccination protocols for camelids are empirically derived. Most animals should receive Clostridium perfringens type C and D vaccinations and tetanus toxoid. In rabies endemic areas, a rabies vaccine should be administered. Vaccination against West Nile virus and the equine encephalitides viruses (ie, Eastern equine encephalitis [EEE], Western equine encephalitis [WEE], and Venezuelan equine encephalitis [VEE] viruses) may be needed in some areas. In regions where common liver fluke (Fasciola hepatica) infections or snake envenomations are a problem, use of polyvalent clostridial vaccines against Clostridium novyi, Clostridium septicum, Clostridium sordellii, and Clostridium chauvoei have been used.

One successful approach has been to give an initial vaccination at 3 months of age, a booster 30 days later, and annual boosters thereafter. Llamas and alpacas are immunocompetent at birth, so neonatal vaccination can begin in the first week of life, followed by two boosters at 3-week intervals. Abortions secondary to Leptospira spp infections are regionally a problem and can usually be prevented using an initial vaccination, followed by boosters 2 times a year. Vaccinations against other viral diseases should only involve use of killed vaccines.

Pregnant animals should receive vaccine boosters 4 to 6 weeks before parturition to maximize antibody transfer to the neonate in utero.

Skull and teeth, llama

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Courtesy of Dr. Bradford B. Smith and Dr. Karen I. Timm.

Maxilla and mandible, llama

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Courtesy of Dr. Bradford B. Smith and Dr. Karen I. Timm.

Mandibular abscess, llama

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Courtesy of Dr. LaRue Johnson.

Camelids have a small oral cavity with an elongated soft palate and narrow oropharynx. The esophagus of camelids is similar to that of ruminants. The stomach has three distinct compartments (C1, C2, and C3) that correlate poorly with the four chambers of the ruminant stomach. Only the aborad fifth of C3 is analogous to the abomasum or acid-secreting monogastric stomach. The spiral colon is generally a flat, single spiral and is prone to obstruction when the centripetal loop turns to become centrifugal. Camelids are not ruminants, although they do eructate, regurgitate, and remasticate and are sometimes called pseudoruminants. They are considered foregut fermenters in the C1 and C2 compartments.

In llamas and alpacas, the dental formula is 2 × (I 1/3; C 1/1; PM 1–2/1–2; M 3/3) = 28 to 32 for permanent teeth and 2 × (I 1/3; C 1/1; PM 2–3/1–2; M 0/0) = 18 to 22 for deciduous teeth. The dental pad of llamas and alpacas is similar to that of a cow. At birth, the first two pairs of lower incisors are normally through the gum line; lack of eruption is one indication of prematurity. The central, middle, and lateral mandibular deciduous incisors are replaced at approximately 2–2½, 3–3½, and 4–6 years, respectively, although determining age by the teeth is notoriously inaccurate in these species.

The upper and lower canine teeth are unique in camelids and are known as fighting teeth. They can grow to more than 3 cm in length. These teeth are used when males spar and can be dangerous to human handlers. These teeth usually need to be cut flush to the gum with obstetrical wire, a small rasp, or a rotary grinder tool after their eruption at 18–24 months of age. Sexually intact males may need annual recutting of these teeth. Tooth removal is impractical because of very deep, curved roots. Patients should be sedated first and positioned within a chute. Growth of fighting teeth usually stops after castration. Fighting teeth in most females barely penetrate the gumline and seldom, if ever, need to be cut. If castration is planned for a particular male, eruption of the fighting teeth signals an ideal time to schedule both procedures.

The teeth of camelids rarely need to be floated, even though the upper and lower cheek teeth do not oppose each other and do not wear evenly. Having sharp cheek teeth is normal. Deciduous teeth are occasionally retained and may require removal at some point. In alpacas, the incisors grow continuously and have an open pulp cavity. Premolar and molar occlusion should be checked and problems corrected in older animals exhibiting difficulty in chewing.

Abscessed lower second premolars, and first and second molars, can present as hard, well-developed swellings on the lateral surface of the mandible over the affected teeth. A draining tract may or may not be present. The area is usually not painful on palpation, and most animals maintain body condition. Prolonged antimicrobial therapy is palliative, although rarely curative. Tooth extraction—which is curative—usually requires making a lateral incision over the affected teeth, splitting the tooth because of the divergent roots, and repelling the tooth into the oral cavity. This should only be done under general anesthesia. Care should be taken during extraction to avoid mandibular fracture.

Jaw osteomyelitis, or lumpy jaw, may occur secondarily to tooth root abscesses. Patients may present with drooling, weight loss, and ill thrift. Appropriate radiographic views of the skull and teeth, CT scan, or MRI of the head should be performed for diagnosis prior to tooth extractions and dental surgery.

Nail trimming, llama

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Courtesy of Dr. LaRue Johnson.

Immersion foot, llama

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Courtesy of Dr. LaRue Johnson.

Some llamas and alpacas rarely need foot care, whereas others require nail trimming every 2–3 months. Diet, genetics, conformation, and environment likely play a role, but in any event, the feet of camelids should be examined regularly.

Animals should be trained to allow their feet to be picked up and handled so that the pads, nails, and the area between the toes can be examined, cleaned, and worked on, if needed. Sedation is not needed for trimming with adequate training. Ideally, the animal should be in a chute for foot trimming, although very well-trained animals will stand still without restraint. Garden clippers and shears work well to trim nails, as do smaller foot tools designed for goats and sheep. Nails should be trimmed flush with the bottom of the pad.

Occasionally, and especially with overgrown toes, quicking may occur. Although generally inconsequential, it can be uncomfortable and should be avoided. The pads should be mostly left alone although inspected for abnormalities. If the foot is extremely overgrown or misshapen, radiographs should be taken first to determine the location of the underlying bones in relation to the external structures. Problem feet should be worked on gradually, with trimming staged so as not to make the animal unduly lame or uncomfortable. Camelids maintained in overly wet areas will often develop fungal infections (thrush) and infections between the toes and on the pads. If these are identified, they require treatment in conjunction with changes in management and husbandry.

Routine care for camelids includes annual vaccinations; parasite diagnosis, management, and control; cutting of fighting teeth; foot care; and shearing. Disease testing may be required for interstate travel. Routine tuberculosis surveillance using the tuberculin purified protein derivative (PPD) skin test is not recommended because animals will often become reactors. Tuberculosis is discussed in the section on infectious diseases. Physical examination, including blood tests and urinalysis, is recommended at least once a year. See table Vital Signs in Adult Camelids 

Shearing thermal burn, llama

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Courtesy of Dr. LaRue Johnson.

Barrel cut, llama

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Courtesy of Dr. Ellen Wiedner.

Camelids often struggle with heat, and shearing off their fiber before hot weather is a necessity. Several cuts are possible, and a simple barrel cut, with fur shorn in a wide swath around the torso, is sometimes adequate, but shearing the animal entirely may be necessary for adequate comfort. Large, electric shears should be used, and specialty blades for camelids make an onerous job easier. Complications associated with shearing include lacerations that may occur where there are loose folds of skin (eg, near the axilla). These often heal uneventfully with or without suturing, although some can require antimicrobial therapy.

Hot shears can lead to burns resulting in thick scabs, usually on the dorsum of the back, that may resemble wool rot. A history of shearing by a novice often helps confirm the diagnosis. Antimicrobial ointment is generally beneficial for these iatrogenic lesions, but sunburn also can occur after shearing, especially in light-skinned animals. If found in the acute stage, protection from further exposure and application of aloe vera lotion have proved useful. Later appearance of sunburned sites varies from mild peeling to ulcers.