Common Diseases of Dairy Cows and Their Prevention and Treatment Methods, Part Two
Common Diseases of Dairy Cows and Their Prevention and Treatment (Part Two)
(Agricultural Wealth Network) V. Parturient Paresis
Parturient paresis, also called milk fever, is a severe metabolic disease that occurs suddenly around the time of calving in cows. This disease mainly affects high-yielding dairy cows within three days after calving, and mostly occurs at the 3rd to 6th parity. Disturbances in the supply of calcium and phosphorus in the feed, in intestinal absorption, and in endocrine function, together with the consumption of large amounts of calcium by fetal growth and milk secretion, cause a sharp drop in blood calcium concentration, which is an important cause of this disease. It is characterized by loss of consciousness and paralysis of the limbs. At the beginning of the disease, appetite decreases or is completely lost; rumination, rumen motility, defecation and urination stop; milk yield decreases, the animal is depressed and shows mild restlessness; in some cases, after restlessness appears, the cow becomes alarmed, bellows, acts violently, and stares fixedly. A few hours after the initial symptoms appear, the affected cow becomes paralyzed on the ground, and soon afterward depression of consciousness and loss of perception occur. The sick cow lies in a characteristic posture, with the limbs flexed beneath the body and the head bent backward toward one side of the chest, or the head and neck curved in an "S" shape. A drop in body temperature is another feature of this disease. If this disease is not treated in time, it rarely resolves, and in most cases the condition worsens within 12 to 24 hours, ultimately ending in death from respiratory failure.
Treatment: 1. Restore blood calcium to normal levels as quickly as possible. A commonly used method is intravenous injection of 500 milliliters of 20% to 25% calcium borogluconate injection (containing 4% boric acid) (the injection should take no less than 10 minutes), or 1000 milliliters of 10% calcium gluconate, or 500 milliliters of 5% calcium chloride by slow intravenous injection. 2. Use an udder insufflator to pump air into the udder, increasing pressure within the udder and reducing milk secretion so as to reduce calcium consumption in the body.
It is recommended to begin feeding a low-calcium, high-phosphorus feed 2 weeks before calving to stimulate the function of the parathyroid glands, promote parathyroid secretion, and thereby improve the ability to absorb and mobilize bone calcium. Feeding vitamin D and promptly increasing the calcium and phosphorus content of the ration after calving can reduce the incidence of the disease.
VI. Metritis
Metritis is inflammation of the uterine mucosa caused by improper care during calving or the postpartum period (such as improper assistance during calving), retained placenta, uterine prolapse, and infection during breeding. Purulent catarrhal endometritis is inflammation of the superficial layer of the mucosa. Purulent secretions flow out from the uterus. Pseudomembranous metritis occurs when the deep layer of the mucosa is also damaged, with fibrinous exudate in the uterus, and in severe cases the uterine muscle layer may become necrotic. The sick cow shows obvious systemic symptoms, with elevated body temperature, reduced appetite, and depression. Chronic purulent metritis always develops from the acute form. Clinically, there are generally no external symptoms, but affected cows have irregular estrus; some do show estrus and ovulation but fail to conceive after repeated breeding, and even if they do conceive, they often abort in early pregnancy, greatly affecting the reproductive performance of the herd.
Treatment: Stop the spread of infection, clear the purulent secretions from the uterine cavity, and increase uterine tone and the uterus's self-cleansing ability. First flush with medicinal solution, then massage (through the rectum), drain the flushing fluid from the uterine cavity as thoroughly as possible, and then inject antibacterial agents and uterine contractants.
Prevention: This disease is prevented by maintaining good environmental hygiene and by timely and proper treatment of primary diseases.
VII. Foot Rot
Foot rot is a common hoof disease in dairy cows. Improper feeding and management and insufficient exercise are predisposing factors. It is mainly caused by uneven bedding in cow sheds and exercise yards, excessive wear of the sole, and puncture wounds from foreign objects that become infected with Fusobacterium necrophorum and pyogenic bacteria; in addition, the hooves are often soaked in manure and urine sewage, which promotes the occurrence of the disease. The affected hoof becomes swollen and hot, the skin between the toes becomes congested and swollen, the wound becomes infected and ulcerated, and foul-smelling inflammatory secretions are discharged, which then spread to the coronary band and the rear part of the hoof and may also damage tendons, ligaments, and joints, forming purulent inflammation. Sometimes the sole ulcerates, forming cavities of varying sizes filled with dirty gray or dark brown necrotic tissue and foul-smelling pus. This disease mostly affects both hind hooves. If only one hoof is affected, the cow often lifts the affected hoof and walks by hopping on the healthy hoof, which affects feed intake and causes milk yield to decline. If both hind hooves are affected, the cow prefers to lie down and is unwilling to move or stand.
Treatment: When lameness and hoof abnormalities are seen, the hooves should be examined immediately, especially by washing and examining the sole and the interdigital space. When mild foot rot is limited to the superficial layer, apply 3% to 5% potassium permanganate lanolin ointment. When the hoof is swollen and lameness is obvious, use a warm foot bath with 1% potassium permanganate solution. If the sole has already ulcerated into a cavity with pus and necrotic tissue, wash the hoof with disinfectant solution, thoroughly remove the necrotic tissue with scissors, disinfect with 5% concentrated iodine tincture, sprinkle on antibacterial drugs, apply a cotton plug soaked in formalin and pine tar, and bandage it. Then wrap the hoof with waterproof plastic sheeting and change the dressing once every 2 to 3 days.
Prevention: Strengthen feeding and management, and pay attention to the cleanliness, hygiene, and dryness of the barn and exercise yard.
VIII. Babesiosis
Bovine babesiosis is a blood protozoal disease caused by infection with Babesia bigemina, and the parasite lives in the red blood cells of cattle. Its shapes include ring, oval, pear, and amoeboid forms. The pear-shaped body is longer than the radius of the red blood cell, and two parasites are often joined at their pointed ends at an acute angle. The incubation period is 8 to 15 days, sometimes longer. The first sign is a rise in body temperature to 40 to 41.5°C, which can last for one week or longer. The sick cow is depressed, has reduced appetite, and stops ruminating. Anemia is obvious, and up to 75% of red blood cells may be destroyed, usually with the appearance of hemoglobinuria. In the early stage of the disease, the parasite infection rate of red blood cells is generally 10% to 15%, while in mild cases it is only 2% to 3%, and in some cases the parasite is very difficult to find. The mortality rate can reach 50% to 90%. Any cattle farm that has introduced cattle from other places should pay close attention to this disease. Once body temperature rises and the parasite can be found in a blood smear, treat it as this disease.
Treatment: Specific therapeutic drugs for this disease already exist, such as diminazene, Bayer 205, and acriflavine, and as long as they are used promptly and correctly, satisfactory results can be achieved.
IX. Tuberculosis and Brucellosis
Tuberculosis is a chronic zoonotic infectious disease caused by Mycobacterium tuberculosis. The pathogen parasitizes lung tissue and forms nodules, which later become caseous necrosis and form cavities. Affected cows gradually lose weight and become weak. In addition to the lungs, there may also be mammary tuberculosis, lymphatic tuberculosis, and intestinal tuberculosis, etc. According to pathogenicity, Mycobacterium tuberculosis can be divided into the human type, bovine type, and avian type, but the types can infect one another, and humans can become infected through the air or by eating contaminated milk or other food.
Brucellosis is a chronic zoonotic infectious disease caused by Brucella. Dairy cows are most susceptible to Brucella. The clinical features of the disease are abortion or premature birth, so it is also called infectious abortion, and it often causes metritis; after bulls are infected, orchitis occurs, resulting in azoospermia and affecting reproductive capacity. After humans are infected with Brucella, remittent fever appears, along with lethargy and weakness, and reduced ability to live and work; the condition is very stubborn and difficult to cure.
Because dairy cows are the most susceptible animals to tuberculosis and brucellosis and can easily transmit them to humans, strengthening the prevention and treatment of tuberculosis and brucellosis (commonly known as the "two diseases") in dairy cows is of great significance for public health.
The prevention and treatment of the "two diseases" should continue to follow the following principles:
1. Accept the management of the animal epidemic prevention supervision department and regularly complete quarantine monitoring for the "two diseases".
2. Under the supervision of the local animal epidemic prevention department, conduct at least one test each year for tuberculosis (using the tuberculin test - intradermal injection and eye instillation) and brucellosis (blood collection for testing - tube agglutination method). Positive cattle detected should be culled immediately.
3. When introducing dairy cows, the epidemic situation in the place of origin must be understood, and dairy cows must absolutely not be introduced from farms in epidemic areas of the "two diseases". Even for non-epidemic areas, a quarantine certificate issued by the local animal epidemic prevention department within the past month is required. After transport back, they should still be isolated for at least 3 months, and only those proven negative by another quarantine test may be moved into the main herd for rearing.
4. For on-farm workers, regular health examinations should be conducted 1 to 2 times per year. If cattle with the two diseases are found, they should be promptly removed and given treatment, and at the same time the whole herd should be comprehensively examined.
5. Maintain environmental hygiene on the dairy farm and carry out regular disinfection.
Parturient paresis, also called milk fever, is a severe metabolic disease that occurs suddenly around the time of calving in cows. This disease mainly affects high-yielding dairy cows within three days after calving, and mostly occurs at the 3rd to 6th parity. Disturbances in the supply of calcium and phosphorus in the feed, in intestinal absorption, and in endocrine function, together with the consumption of large amounts of calcium by fetal growth and milk secretion, cause a sharp drop in blood calcium concentration, which is an important cause of this disease. It is characterized by loss of consciousness and paralysis of the limbs. At the beginning of the disease, appetite decreases or is completely lost; rumination, rumen motility, defecation and urination stop; milk yield decreases, the animal is depressed and shows mild restlessness; in some cases, after restlessness appears, the cow becomes alarmed, bellows, acts violently, and stares fixedly. A few hours after the initial symptoms appear, the affected cow becomes paralyzed on the ground, and soon afterward depression of consciousness and loss of perception occur. The sick cow lies in a characteristic posture, with the limbs flexed beneath the body and the head bent backward toward one side of the chest, or the head and neck curved in an "S" shape. A drop in body temperature is another feature of this disease. If this disease is not treated in time, it rarely resolves, and in most cases the condition worsens within 12 to 24 hours, ultimately ending in death from respiratory failure.
Treatment: 1. Restore blood calcium to normal levels as quickly as possible. A commonly used method is intravenous injection of 500 milliliters of 20% to 25% calcium borogluconate injection (containing 4% boric acid) (the injection should take no less than 10 minutes), or 1000 milliliters of 10% calcium gluconate, or 500 milliliters of 5% calcium chloride by slow intravenous injection. 2. Use an udder insufflator to pump air into the udder, increasing pressure within the udder and reducing milk secretion so as to reduce calcium consumption in the body.
It is recommended to begin feeding a low-calcium, high-phosphorus feed 2 weeks before calving to stimulate the function of the parathyroid glands, promote parathyroid secretion, and thereby improve the ability to absorb and mobilize bone calcium. Feeding vitamin D and promptly increasing the calcium and phosphorus content of the ration after calving can reduce the incidence of the disease.
VI. Metritis
Metritis is inflammation of the uterine mucosa caused by improper care during calving or the postpartum period (such as improper assistance during calving), retained placenta, uterine prolapse, and infection during breeding. Purulent catarrhal endometritis is inflammation of the superficial layer of the mucosa. Purulent secretions flow out from the uterus. Pseudomembranous metritis occurs when the deep layer of the mucosa is also damaged, with fibrinous exudate in the uterus, and in severe cases the uterine muscle layer may become necrotic. The sick cow shows obvious systemic symptoms, with elevated body temperature, reduced appetite, and depression. Chronic purulent metritis always develops from the acute form. Clinically, there are generally no external symptoms, but affected cows have irregular estrus; some do show estrus and ovulation but fail to conceive after repeated breeding, and even if they do conceive, they often abort in early pregnancy, greatly affecting the reproductive performance of the herd.
Treatment: Stop the spread of infection, clear the purulent secretions from the uterine cavity, and increase uterine tone and the uterus's self-cleansing ability. First flush with medicinal solution, then massage (through the rectum), drain the flushing fluid from the uterine cavity as thoroughly as possible, and then inject antibacterial agents and uterine contractants.
Prevention: This disease is prevented by maintaining good environmental hygiene and by timely and proper treatment of primary diseases.
VII. Foot Rot
Foot rot is a common hoof disease in dairy cows. Improper feeding and management and insufficient exercise are predisposing factors. It is mainly caused by uneven bedding in cow sheds and exercise yards, excessive wear of the sole, and puncture wounds from foreign objects that become infected with Fusobacterium necrophorum and pyogenic bacteria; in addition, the hooves are often soaked in manure and urine sewage, which promotes the occurrence of the disease. The affected hoof becomes swollen and hot, the skin between the toes becomes congested and swollen, the wound becomes infected and ulcerated, and foul-smelling inflammatory secretions are discharged, which then spread to the coronary band and the rear part of the hoof and may also damage tendons, ligaments, and joints, forming purulent inflammation. Sometimes the sole ulcerates, forming cavities of varying sizes filled with dirty gray or dark brown necrotic tissue and foul-smelling pus. This disease mostly affects both hind hooves. If only one hoof is affected, the cow often lifts the affected hoof and walks by hopping on the healthy hoof, which affects feed intake and causes milk yield to decline. If both hind hooves are affected, the cow prefers to lie down and is unwilling to move or stand.
Treatment: When lameness and hoof abnormalities are seen, the hooves should be examined immediately, especially by washing and examining the sole and the interdigital space. When mild foot rot is limited to the superficial layer, apply 3% to 5% potassium permanganate lanolin ointment. When the hoof is swollen and lameness is obvious, use a warm foot bath with 1% potassium permanganate solution. If the sole has already ulcerated into a cavity with pus and necrotic tissue, wash the hoof with disinfectant solution, thoroughly remove the necrotic tissue with scissors, disinfect with 5% concentrated iodine tincture, sprinkle on antibacterial drugs, apply a cotton plug soaked in formalin and pine tar, and bandage it. Then wrap the hoof with waterproof plastic sheeting and change the dressing once every 2 to 3 days.
Prevention: Strengthen feeding and management, and pay attention to the cleanliness, hygiene, and dryness of the barn and exercise yard.
VIII. Babesiosis
Bovine babesiosis is a blood protozoal disease caused by infection with Babesia bigemina, and the parasite lives in the red blood cells of cattle. Its shapes include ring, oval, pear, and amoeboid forms. The pear-shaped body is longer than the radius of the red blood cell, and two parasites are often joined at their pointed ends at an acute angle. The incubation period is 8 to 15 days, sometimes longer. The first sign is a rise in body temperature to 40 to 41.5°C, which can last for one week or longer. The sick cow is depressed, has reduced appetite, and stops ruminating. Anemia is obvious, and up to 75% of red blood cells may be destroyed, usually with the appearance of hemoglobinuria. In the early stage of the disease, the parasite infection rate of red blood cells is generally 10% to 15%, while in mild cases it is only 2% to 3%, and in some cases the parasite is very difficult to find. The mortality rate can reach 50% to 90%. Any cattle farm that has introduced cattle from other places should pay close attention to this disease. Once body temperature rises and the parasite can be found in a blood smear, treat it as this disease.
Treatment: Specific therapeutic drugs for this disease already exist, such as diminazene, Bayer 205, and acriflavine, and as long as they are used promptly and correctly, satisfactory results can be achieved.
IX. Tuberculosis and Brucellosis
Tuberculosis is a chronic zoonotic infectious disease caused by Mycobacterium tuberculosis. The pathogen parasitizes lung tissue and forms nodules, which later become caseous necrosis and form cavities. Affected cows gradually lose weight and become weak. In addition to the lungs, there may also be mammary tuberculosis, lymphatic tuberculosis, and intestinal tuberculosis, etc. According to pathogenicity, Mycobacterium tuberculosis can be divided into the human type, bovine type, and avian type, but the types can infect one another, and humans can become infected through the air or by eating contaminated milk or other food.
Brucellosis is a chronic zoonotic infectious disease caused by Brucella. Dairy cows are most susceptible to Brucella. The clinical features of the disease are abortion or premature birth, so it is also called infectious abortion, and it often causes metritis; after bulls are infected, orchitis occurs, resulting in azoospermia and affecting reproductive capacity. After humans are infected with Brucella, remittent fever appears, along with lethargy and weakness, and reduced ability to live and work; the condition is very stubborn and difficult to cure.
Because dairy cows are the most susceptible animals to tuberculosis and brucellosis and can easily transmit them to humans, strengthening the prevention and treatment of tuberculosis and brucellosis (commonly known as the "two diseases") in dairy cows is of great significance for public health.
The prevention and treatment of the "two diseases" should continue to follow the following principles:
1. Accept the management of the animal epidemic prevention supervision department and regularly complete quarantine monitoring for the "two diseases".
2. Under the supervision of the local animal epidemic prevention department, conduct at least one test each year for tuberculosis (using the tuberculin test - intradermal injection and eye instillation) and brucellosis (blood collection for testing - tube agglutination method). Positive cattle detected should be culled immediately.
3. When introducing dairy cows, the epidemic situation in the place of origin must be understood, and dairy cows must absolutely not be introduced from farms in epidemic areas of the "two diseases". Even for non-epidemic areas, a quarantine certificate issued by the local animal epidemic prevention department within the past month is required. After transport back, they should still be isolated for at least 3 months, and only those proven negative by another quarantine test may be moved into the main herd for rearing.
4. For on-farm workers, regular health examinations should be conducted 1 to 2 times per year. If cattle with the two diseases are found, they should be promptly removed and given treatment, and at the same time the whole herd should be comprehensively examined.
5. Maintain environmental hygiene on the dairy farm and carry out regular disinfection.