1. Heat Wave.
2. Effects of heat wave in dogs.
3. Risk Conditions Associated with Heatstroke.
4. Physiologic Effects of Hyperthermia.
5. Effects and Consequences of ABC Surgery in hyperthermia condition.
Effects of Heat Wave in Dogs and Its Consequences in Animals Undergoing Animal Birth Control Surgery:
What is a heat wave?
Heat wave is a prolonged period of excessively hot weather, which may be accompanied by high humidity, especially in oceanic climate countries. While definitions vary, a heat wave is measured relative to the usual weather in the area and relative to normal temperatures for the season. Temperatures that people from a hotter climate consider normal can be termed a heat wave in a cooler area if they are outside the normal climate pattern for that area.
A heat wave is considered extreme weather and a danger because heat and sunlight may overheat the body.
A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season in the North-Western parts of India.
Heat Waves typically occur between March and June, and in some rare cases even extend till July. The extreme temperatures and resultant atmospheric conditions adversely affect animals living in these regions as they cause physiological stress, sometimes resulting in death.
A heat wave warning has been issued to all statesnby the Indian Meteorological Department (IMD). According to the IMD, parts of the country will see a heat wave and temperatures will remain between 45 and 48.5 degrees Celsius.
The heat wave will continue till June, some states will remain hot and humid.
Effects of heat wave in dogs:
Hyperthermia is an elevation in body temperature that results when heat production exceeds heat loss. Core body temperature rises above the established normal range (99.8-102.8oF/ 37.6-39.3oC) in the homoeothermic canine.
Hyperthermia leads to heat stress and heat stroke.
Heat stroke is a form of non-fever hyperthermia that occurs when heat-dissipating mechanisms of the body cannot accommodate excessive external heat. Typically associated with temperature of 106° F (41° C) or higher without signs of inflammation, a heat stroke can lead to multiple organ dysfunction.
Normal Thermoregulatory Responses to Hyperthermia are as follows:
1. Thermoregulatory Center:
Homeotherms, or warm-blooded animals, have thermoregulatory mechanisms controlled by brain which work to maintain a normal body temperature.
2. Physiologic Responses:
a)Evaporative cooling –The panting mechanism is an efficient way of increasing the evaporative heat loss. It also is the main mechanism of temperature reduction in the dog. The panting mechanism along with increased salivation during panting greatly increases the evaporative cooling, which may account for up to 60% of heat dissipation.
b) Increased blood flow - Normally, high environmental temperatures cause peripheral blood vessels to dilate, allowing more blood to flow to the skin and dissipate heat.
3. Behavioral Responses:
a) Seek cool surfaces to lie upon.
b) Seek shade, getting out of direct sun.
c) Seek water.
d) Seek breezes.
e) Minimize/avoid activity.
Risk Conditions Associated with Heatstroke:
1. Factors that inhibit heat dissipation:
a) Lack of acclimatization to the weather – normal healthy dogs may require about 20 days to a month to acclimate to warmer weather.
b) High/hot ambient temperatures.
d) Confinement with poor ventilation.
e) Water deprivation, dehydration.
g) Extremes of age - very young, very old.
h) Drugs - Sedatives, Anesthetics.
2. Factors that contribute to heat production:
a) Simple exposure to excessive environmental temperatures.
b) Exercise – minimal in hot, humid environment to strenuous in moderate environment.
Muscle metabolism accounts for up to 80% of the body’s overall heat production during physical activity.
3. Medical conditions that predispose to heatstroke:
a) Cardiovascular disease.
b) Central nervous system disease.
c) Respiratory problems.
d) Electrolyte imbalance.
4. Other conditions that predispose to heatstroke:
a) Fatigue - canine is not moving as efficiently and must work harder to perform the same job.
b) Ground surface – higher ground temperature, which also reflect heat back up to canine.
Physiologic Effects of Hyperthermia:
a) Increased metabolic rate and oxygen consumption.
b) Decreased function of heart causing poor organ tissue blood supply, muscle degeneration.
d) Rapid heart rate, irregular heartbeats.
f) Stoppage of the heart and breathing (cardiopulmonary arrest).
a) Lung infection- Pneumonia.
b) Laryngeal swelling obstructing the air pathway.
c) Fluid build-up in the lungs; sudden breathing distress.
d) Acute Respiratory Distress due to inflammatory response or infection secondary to bacterial.
a) Brain swelling.
b) Bleeding inside brain.
c) Breakdown of red-muscle tissue leading to difficulty in movements, breathing.
a) Electrolyte imbalance.
c) Excessive drooling.
d) Unconsciousness in which the dog cannot be stimulated to be awakened.
a) Vomiting blood.
b) Passage of blood in the bowel movement or stool.
c) Black, tarry stools.
d) Mucosal barrier breakdown - Direct thermal injury to stomach and intestine mucosal lining causing ulcers in stomach and intestine.
e) Bacterial infection.
a) Production of only small amounts of urine or no urine.
b) Sudden (acute) kidney failure.
b) Death of liver cells.
c) Immune compromise.
a) Muscle tremors.
b) Wobbly, in coordinated movement.
d) Increased body temperature - above 103° F
e) Reddened gums and moist tissues of the body.
f) Decreased blood glucose levels.
Effects and Consequences of ABC Surgery in hyperthermia condition:
A. Capture & Handling of Stray Dogs causes
1. Anxiety and Stress.
2. Increased activity in hot weather to avoid capture.
3. Difficulty in breathing when using sack/rope method.
B. Transport and housing:
1. Confinement within closed space.
2. Inadequate spacing and ventilation.
1. Stress causes increased heart rate, risk of irregular heart beat.
2. Strenuous exercise greatly increases the total body heat.
3. Handling interferes with normal panting mechanism which can be detrimental leading to serious effects within minutes.
4. Forced confinement in a hot environment, the animal's thermoregulatory mechanisms become ineffective at dissipating the body's extra heat.
5. Heat waves are also often accompanied by periods of stagnant air leading to increases in air pollution and increase in respiratory problems.
C. Preoperative preparation:
Starvation can lead to
2. Electrolyte disturbances.
3. Decreased blood glucose levels.
4. Stress response activation.
5. Increased heart rate.
6. Decreased blood volume.
Effects of Sedatives:
1. Decreases the brain function. Thermoregulation will be affected.
2. Decreased response to heat like panting.
3. Decreased breathing efforts which impair oxygenation level in blood.
4. Decreased risk of cough reflex
5. Increased risk of vomiting, increases the risk of aspiration and lung infection
6. Vomiting can trigger bleeding from stomach or intestine ulcers.
7. Increases the risk of compromising the animal's ability to respond to heat in animals with any disease of the heart or lungs.
8. Decreased salivation which impairs heat dissipation.
1. Increased risk of kidney injury and failure.
D. Post operative complications:
1. Surgical pain.
2. Drug effects.
3. Abnormal heart beat.
4. Low BP.
5. Bleeding from multiple sites: wound site, inside the body, possibly due to low platelets and abnormal bleeding and clotting mechanism.
6. Sepsis - widespread infection.
7. Systemic inflammatory response.
8. Dehydration and brain damage.
9. Loss of Thermoregulatory mechanisms.
10. Cardio respiratory arrest.
E. After release
Difficulties encountered by the animal are:
1. Resting place.
No proper place with adequate shade to prevent exposure to heat is available at all times.
Stress response is heightened by the release of animal in the society in the struggle for proper place to rest, for food and water leading to increased physical activity and fatigue. The canine would be not able to move as efficiently and have to work harder which also contributes to increase in body heat production.
3. Food availability and safety.
- Reduced availability of safe food and drinking water for stray dogs.
- Food poisoning - Higher air temperatures can increase cases of Salmonella and other bacteria-related food poisoning because bacteria grow more rapidly in warm environments. These diseases can cause gastrointestinal disease and, in severe cases, death.
4. Heat Wave creating or worsening mental health impacts such as depression and canine post-traumatic stress disorder (PTSD).
5. Depressed immunity leading to increased susceptibility to infections.
6. Surgical pain.
7. Increased risk of heat stroke while lying on the road, which also reflect heat back up to canine.
It is well known that heat wave is a major cause of weather related mortality.
It is widely recognized that extreme climatic conditions constitute a major public health hazard. Heat-related illness may range from trivial heat injury to life-threatening emergencies. It is expected that these heat waves may increase in frequency, severity and duration to a discernible extent. mortality.
The stray animal population is particularly at a high risk of developing complications and heat-related
Taking into consideration of the effects of heat wave on canines and its potential lethal consequences in dogs undergoing ABC SURGERY, there is definite risk of detrimental effects of hot weather in animal’s physiology and behavior which can lead to increased suffering and death.
For Animal Rights,
Director R & D