Chapter 25: Dogs
Body weight | Adult male: 13.5–18.5 kg Adult female: 13.5–16 kg Newborn: 350–450 g |
Normal body temperature | 37.5–39.2 °C 99.5–102.5 °F |
Heart rate (beats per minute) | 100–150 |
Respiration rate (breaths per minute) | 20–30 |
Life span (years) | 10–15 |
Daily consumption | Feed: 25–40 g per kg BW Water: 25–35 mL per kg BW |
Puberty age (months) | Male: 7–8 Female: 7–9 |
Sexual cycle duration (days) | 7–10 |
Sexual cycle type (in lab conditions) | Monoestrous (spring/fall) |
Gestation period (days) | 59–68 |
Litter size/# of young | 4–8 |
Begins eating solid feed (weeks) | 3–4 |
Age at weaning (weeks) | 6–8 |
Dogs breed year-round, with females in estrus (heat) every 7-8 months for 7-10 days. Pregnancy can be detected through hormone tests, palpation, ultrasound, or X-rays, and visual signs include enlarged teats, weight gain, and a swollen abdomen.
As with cats, the USDA requires that dogs be identified with sturdy tags on a collar, a microchip, or a tattoo. A unique number is usually assigned to each animal at the breeding facility. This number is often tattooed on a hairless area of the dog’s ear.
Cages should be cleaned and the bedding changed daily, and should be regularly sanitized at least every 2 weeks. Floors of pens and runs should be cleaned and sanitized on a regular basis. Make sure that the animals do not get wet during cage or run cleaning.
Feed and water bowls need to be cleaned, and refilled daily, and sanitized at least once every two weeks. Check automatic watering systems every day to ensure that they are functioning properly.
Dogs, like cats, are primarily carnivores but need a balanced diet that includes meat products, grains, and vegetables. Commercial dog diets offer balanced nutrition; the amount of feed required is determined by the dog’s size, age, health, activity, and whether it is pregnant or lactating. Special research requirements may also be a factor in the amount of feed offered to the dog. Adult dogs are generally fed once a day; leftover feed should be removed after a reasonable period of time. Fresh, clean water should be available ad libitum.7
In groups, dogs tend to establish a social hierarchy; make sure that the less dominant animals in the group get their share of feed and water by providing sufficient feed and water bowls for all animals.
Modern dogs require human interaction, training, and enrichment activities like toys and exercise. Environmental enrichment, including ample space and agility equipment, is essential and must be documented.
Stiff body movements or an unwillingness to move are indications of pain in dogs. A dog with less severe pain may just appear restless. Shivering, heavy panting, whimpering or howling are also signs of pain or distress. Dogs may bite or scratch irritated or painful areas.
A dog in pain is often more apprehensive and aggressive than normal. A sick dog, on the other hand, will often try to isolate itself in a corner of its cage, often in a curled position with its feet tucked under and its head and tail curled around the body. Sick or injured dogs usually will not respond to the handler’s call and may tremble, growl, snarl, or whimper.
An overdose of barbiturates administered by trained personnel is an acceptable method for euthanasia. An overdose of inhalant anesthetics or potassium chloride delivered to the heart while the dog is under anesthesia may also be used. As with all other laboratory animals, death must be verified prior to disposal. Your institution’s SOPs may require an additional procedure to be performed for this verification. In addition, the USDA mandates the documentation of euthanasia and retention of the dog’s unique identification tag for one year after disposition, and each unique identification number cannot be reused for 5 years. Carcass disposal should be according to the facility's guidelines