Alpaca Case Clinical Examination and Diagnosis

Key Differential Diagnoses for Weight Loss

  • Parasitic Gastroenteritis (PGE)
    Includes conditions such as (coccidiosis, Haemonchus, Ostertagia, and Nematodirus), which are gastrointestinal parasites that can lead to significant weight loss as they interfere with nutrient absorption and may cause diarrhea. Monitoring for fecal egg counts can provide insight into the presence of these parasites.

  • Dental Disease
    An example is tooth root abscessation, which can cause pain and difficulties in eating, ultimately leading to weight loss. Regular dental examinations are essential to identify issues early, as dental problems can severely impact the animal's health and feeding behavior.

  • Skin Disease
    Skin lesions may indicate infections or infestations by parasites such as mites or lice. These conditions can lead to discomfort and weight loss due to decreased feeding due to itchiness or pain. Careful skin examinations can help in early diagnoses.

  • Lameness
    Poor mobility resulting from physical injury or joint problems can limit an alpaca’s ability to feed, contributing to weight loss. Evaluating limb health and gait can help identify any underlying issues that may need addressing.

  • Chronic Disease
    Consider notifiable diseases such as (bTB) and neoplasia. These conditions often manifest with systemic signs including weight loss, and are particularly crucial to consider in older animals where the likelihood of chronic conditions increases.

Normal Vital Signs of Adult Alpacas

  • Resting Respiratory Rate: 1-30 breaths/minute

  • Resting Heart Rate: 60-90 beats/minute

  • Stomach Compartments: Alpacas have 3 compartments in their stomach, which allows for efficient digestion.

  • C1 Contractions: Healthy adults should exhibit 3-5 contractions per minute, which signifies good ruminal function.

  • Rectal Temperature: Normal temperature ranges from 37.5°C - 38.9°C.

  • Weight: The normal weight range for alpacas is 50-90 kg, and careful monitoring is necessary to identify any significant changes indicating health issues.

Clinical Examination Findings for Molly

  • Temperature: 38.2°C (indicative of a slight fever, possibly due to infection).

  • Respiratory Rate: 21 beats/minute (within normal limits, suggesting no respiratory distress).

  • Heart Rate: 86 beats/minute (within normal range).

  • C1 Turnover: 4 contractions/minute (slightly elevated, could indicate increased rumen activity possibly due to stress or dietary change).

  • Body Condition Score: 2.0 (indicating poor body condition, highlighting the need for nutritional intervention).

  • Skin Findings: Presence of erythema and alopecia on the dorsum and legs, which may warrant further investigation into underlying conditions or parasites.

  • Lameness: No signs present, suggesting that mobility issues may not be contributing factors to her weight loss.

Presenting Problems in Molly

  • Dermatological Lesions

  • Poor Body Condition Score

Differential Diagnoses for Skin Condition

  • Psoroptic Mange: A contagious skin disease caused by mites, leading to intense itching and hair loss.

  • Sarcoptic Mange: Another type of mite infestation that can cause similar issues as psoroptic mange.

  • Chorioptes: A type of mange mite affecting the skin, usually in the lower limbs and can cause dermatitis.

  • Lice: Can cause skin irritation and weight loss through pruritus.
    Microthoracius species or Bovicola breviceps are specific lice species to monitor for.

  • Bacterial Infections: Such as Staphylococcus aureus or dermatophilosis can lead to lesions and hair loss, causing the alpaca distress and impacting nutritional intake.

Rarer Differentials

  • Pemphigus conditions: Autoimmune skin disease leading to blistering.

  • Contact dermatitis: Reactions to environmental factors could lead to lesions and discomfort.

  • Diet-related pruritus: Potential reactions to certain feed ingredients causing itchy skin.

  • Zinc responsive dermatitis: A deficiency that could cause skin issues, especially if dietary zinc levels are inadequate.

Investigation of Skin Lesions

  • Clip Hair and Scrape:
    Collect hair samples adjacent to affected areas for multiple superficial skin scrapes. Examine under low power microscopy to identify any presence of mites or other organisms.

  • Consider interdigital skin scrapings for chorioptic mange to confirm diagnosis as needed.

  • Swab Samples:
    Collect from lesions with exudate for cytology and bacterial culture to establish if an infection is present.

  • Fungal Disease Suspicions:
    Submit crust, scale, and hair plucks for dermatophyte culture and microscopic evaluation to rule out fungal infections.

Considerations for Sedation

  • Sedative Options:

    • Xylazine +/- Ketamine

    • Note: Not licensed for use in camelids; must use off-label and under the cascade.

    • Dosing: 0.1 to 0.25 mg/kg (xylazine), 2.5 to 3 mg/kg (ketamine), given intramuscularly.

    • It's crucial to monitor vitals closely during sedation.

    • Duration: Approximately 15-20 minutes of sedation, ensuring the animal is monitored continuously.

  • Administration:

    • Subcutaneous: Axillary skin fold for easy access.

    • Intramuscular: Quadriceps muscle generally preferred.

    • Intravenous: Right jugular vein, locate via palpation, not visual prominence, ensuring correct technique.

  • Landmarks:

    • Ventral aspect of the transverse process of cervical vertebrae and the trachea used for intravenous access.

Diagnostic Findings

  • Skin Scrapes Show: Sarcoptes scabiei var. auchinae

    • Important Note: This parasite is zoonotic, necessitating precautions during handling.

Treatment Protocol for Molly

  • Ivermectin Injections: 0.5 to 0.6 mg/kg every 7-10 days for 3-4 treatments for managing sarcoptic mange. Monitoring the effectiveness of the treatment is essential.

  • Keratolytic/Keratoplastic Shampoo:
    Use Sebomild P (Virbac) if scaling/hyperkeratosis appears to improve skin condition, along with regular follow-ups on the skin’s status.

  • Isolation Measures:
    Isolate from other alpacas, especially since the condition is highly contagious. Proper biosecurity measures should be in place.

  • Avoid using contaminated housing for at least 3 weeks, as the mite can survive off the host.

  • Nutritional Support:
    Provide extra food rich in essential nutrients to improve her body condition score, focusing on high-protein and calorie-dense options to promote recovery and weight gain.