寵物小知識
What is Otitis Externa?
Inflammation of ear canal, otitis externa (OE), is a common reason for doggies to be presented to the veterinarian. To understand the cause of the disease, we need to understand the basic anatomy of their ears. A dog's outer ear consists of the ear flap which can be upright or floppy. The ear canal is long narrow and in L-shape ( vertical and horizontal ) as it travels to ear drum. Some breeds such as poodle and schnauzer have very hairy ear canal. This special conformation of ears allows moist and heat trapped especially with floppy ears. This environment favors yeast and bacteria growth thus predispose to the OE. If OE has not been treated and controlled well, the ear canal epithelium becomes thicker and the lumen will be narrower by time thus more heat and moist being trapped. Eventually, the ear canal is obstructed completely in severe case. Other possible causes of external otitis could be due to food allergy, endocrine disease or immune-mediated disease which also predispose yeast and bacteria growth.
Clinical Signs of Otitis Externa
Clinical signs of OE include headshaking, scratching of ears, warm and redness of the ear flaps. Many owners are able to notice the sign at home. We have more cases during summer time due to the hot and humid weather in Hong Kong.
Treatment of Otitis Externa
To confirm the diagnosis of OE, sampling of ear discharge or wax is necessary. A veterinarian will make a smear on a slide and exam microscopically. Otoscopic examination is sometimes not possible because the ear is painful, swelling and filled with discharge. Sedation may be recommended sometimes. Microbial culture of the ear discharge and radiography of tympanic bullae may require in complicated or severe cases.
Treatment of OE depends on the suspected or known cause of OE. Management of pain and itchiness must be included in the initial treatment plan. Effective treatment may require both topical and systemic antimicrobial therapy along with ear wash and pain relief. If OE becomes chronic and the ear canal eventually obstructed, a surgical procedure is required to remove the vertical part of the canal and allow the horizontal part to be exposed.
Recommendation
Regular ear cleaning is important. It is recommended having your dog's ear cleaned once or twice weekly. As I mentioned above, not all OE in dogs are due to the special conformation of the ears. However, some dogs have primary cause of OE such as food allergy, endocrine or immune-mediated disease. Therefore, visiting veterinarian is important to find out the reason of OE besides trying hard to clean your dog's ears.
寵物小知識
A good and correct husbandry of aquatic turtles and land tortoises is very important for their health. Incorrect husbandry set-up can cause variety of diseases and health problems such as swelling of eyes, bubbles from nose and loss of appetite. In severe cases, some of them may die even with treatment. The most important requirement of the husbandry is space, correct temperature and light source and water quality. Therefore, I would like to share the correct husbandry set-up for your aquatic turtles and land tortoises here.
Aquatic Turtle Husbandry
The aquarium should be at least 2 x 3 sq ft big for a single palm-sized aquatic turtle. This set-up can be achieved by using an all-glass aquarium. An external canister filter should be installed which minimizes water change without compromising water quality. If you do not have a filter system, you should change the water every other day. The depth of the water should be deep enough to cover the whole aquatic turtle and allow them to swim, not walking under the water. You should provide a piece of cork bark or rock as the land and basking area. The heat source should be set above the basking area. Splashproof basking lamp should be used. Keep the basking temperature at 30 – 32 C ( 28 – 30 C for hatching and small sized aquatic turtles ) while measuring from the turtle shell. The distance between the turtle shell and the basking lamp should be around 27 cm and usually the basking temperature is provided. The location of UVB source is very important. It should be set at the same side of basking lamp; therefore, they can receive warmth, light and UVB at the same time. Both basking lamp and UVB should be turned on for 10 – 12 hours daily. The opposite side from the basking area is a cold area where should be at about 25 – 28 C. The different temperature between basking and cold area provides a temperature gradient; therefore, they can choose their preferred temperature to avoid being over heated or cooled. If the size of the tank is not big enough, temperature gradient cannot be set.
Tortoise Husbandry
The enclosure should be at least 2 x 3 sq ft big for a single palm-sized tortoise. This set-up can be achieved by using an all-glass aquarium. It is recommended to use a paper towel or puppy toilet pad as the bedding. Intense basking lamp and UVB lamp should be used for land tortoise. Keep the basking area temperature at 32 – 35 C ( 28 – 30 C for hatching and small sized tortoises ) while measuring from the terrapin shell. The distance between the terrapin shell and the basking lamp should be around 27 cm. The UVB should be set at the same side of the basking lamp. Both basking lamp and UVB should be turned on for 10 – 12 hours daily. The opposite side from the basking area is a cold area where should be at about 25 – 28 C. The different temperature between basking and cold area provides a temperature gradient. You should provide a water bath and food near the basking area and change the water daily. A hiding box or cave should be provided at the cold side. Last but not least, humidity and ventilation are also important. Try to keep the humidity at about 70%. Too low or too high can predispose to respiratory disease. Open top or mesh gives better ventilation.
I hope this illustration and article give you more idea about the correct husbandry set-up and provide a better captive environment for your terrapin and tortoise.
Common Questions
1. Why do we need to put UVB and basking lamp on the same side?
Ans: It mimics what the Sun provides therefore aquatic turtles and tortoises will absorb adequate amount of UVB to meet their metabolic requirement with heat and light together.
2. Is it ok to provide a red or blue basking lamp for my tortoise?
Ans: No, it isn’t. The red or blue basking lamp does nothing to do with heat but just colour. They may use for nocturnal reptiles but not aquatic turtles and tortoises.
3. Why does it need temperature gradient?
Ans: Aquatic turtles and tortoises are cold-blooded animals and which means they take on the temperature of their surroundings. Therefore, temperature gradient avoids them from being over heated or cooled.
4. What substrate does a tortoise need?
Ans: Try not to use bark or sandy substrates because they will cause partial intestinal impaction for hatching or small tortoises resulting in loss of appetite.
5. Why does a tortoise need water bath?
Ans: Ensure adequate amount of water access to prevent urolith or cloacolith formation.