Foot and limb are the important supporting organs of cattle, which can support the weight of cattle. Foot and limb disease is a common disease in dairy cow production. Dairy cows are prone to foot and limb diseases, such as hoof deformity, fissure, and lameness. Once symptoms are presented, it is difficult to cure them, and seriously affects production performance and service life. Only by understanding the causes of foot and limb disease can we prevent the occurrence of foot and limb disease from the source. Causes of foot deformity in dairy cows were analyzed. Clinical symptoms and preventive measures of foot deformity in dairy cows were analyzed.
Nutritional factors. The disease can be caused by unreasonable dietary allocation and unbalanced nutritional components, such as minerals, especially low calcium and phosphorus content or unreasonable proportion. Generally speaking, high-yielding dairy cows are fed with more concentrate, which can produce more histamine and endotoxin in the process of metabolism in vivo, and often cause disorder of blood circulation, thus easily causing hoof deformation. When the blood circulation of the hoof is obstructed, especially the capillary reflux of the dermis is obstructed, the microcirculation of the blood is blocked, and numerous plasma components will be exuded, which will accumulate between the horn lobule and the dermal lobule, thus exerting pressure on the dermis covered with nerve endings, resulting in serious pain in the hoof. When dermatitis occurs on the tip wall of the foot, the diseased cattle often carry weight on the heel to relieve the pain, which leads to excessive tension of the deep muscular bonds of fingers and toes, resulting in disorder of the metabolism of the keratinocytes of the foot, and the keratin of the foot gradually softens and finally deforms the foot.
Improper management. Dairy cows are usually fed in house for at least 8 hours a day on a hard and narrow cement cow bed, which causes the hoofs to be continuously subjected to the impulse of the ground. In addition, the cow bed tends to be tilted high and low, and there are huge breasts in the hindquarters, which increases the distance between the limbs and further increases the burden. Dairy cows have to trough three times a day. After troughing, they usually rest in a small area, and lack of movement, which results in that the hoofs of cows can not be abraded normally or wear unevenly, so that they are excessively prolonged and deformed.
If the slot is too low, the cow will stretch its head and neck forward and fork its forelimbs when feeding. At this time, it will cause the forelimbs'inner foot to bear most of the weight of the whole body, causing the inner foot to bear too much weight, causing the distal side wall to gradually replace the negative side, and even to turn upward and roll up toward the axis side. At the beginning, there are only skewed and inclined, which can be called inclined hoof. But if it is not corrected in time, it will gradually become curled hoof with the prolongation of the course of disease, and eventually lead to spiral hoof. In Heilongjiang Province, the temperature in winter is too low and lasts for a long time. However, after thawing in spring, feces and urine are not removed in time, which results in too muddy field. Dairy cows often soak their limbs in turbid water of feces and urine for a long time, and their feet are more prone to deformation, injury and even decay.
The disease is a chronic process. It is often neglected in the absence of appetite disorders and lameness in dairy cows. When a cow has serious hoof deformity, it will generally be difficult to walk, lack of appetite and reduce milk production because of the change of limb position. However, if correct hoof repair can be taken in time, it can still survive for many years. However, if hoof deformity is accompanied by other hoof diseases, such as foot rot, with the spread of inflammation, it will lead to swelling of bulbar and crown joints, skin thickening, accompanied by purulent phenomenon, loss of appetite, tripod jump, even can only lie on the ground, and the prognosis will often lead to poor growth.
Trim the hoof. The main measure to correct hoof deformity is hoof trimming. Cattle usually concentrate on spring and autumn once a year. If serious deformation occurs, they should be trimmed first. When trimming the hoof, first use the hoof pliers to trim the front wall of the lateral finger of the forelimb or the medial toe of the hind limb from the tip of the hoof to 75 mm. Pay attention to that the tongs of the hoof pliers should be perpendicular to the bottom of the hoof.
Next, the sole of the medial or lateral fingers is trimmed with a hoof knife, and the excess corners are removed so that the thickness of the sole is trimmed to 7 mm and the white line is exposed. The front footwall of the other finger (toe) is trimmed until the length is suitable and the sole is trimmed to the same thickness with the trimmed finger (toe) on one side as a reference. Remove the excess corners on the lateral wall of the medial and lateral finger (toe) axis to ensure smooth and smooth finger (toe) clearance. The irregular foot base should also be properly trimmed to ensure that the inclination angle from the far-axis sidewall to the axis sidewall is 15. Face. In addition, dairy cows mainly rely on the far side wall negative edge and hoof ball for hoof load-bearing, that is, the lateral toe of hind limb is more important than the medial toe, so artificial hoof repair should be made to increase the load surface of the lateral toe sole as much as possible, while the lateral toe sole should be cut less appropriately to ensure that the medial toe sole has deep depression.
Make sure that the sole of the lateral finger is of the same height. If serious hoof deformation occurs in dairy cows, it is necessary to carry out multiple repairs. It is forbidden to do too many repairs at one time to avoid bleeding. When repairing hoofs, we should choose appropriate techniques and methods, that is, different types of hoofs should be treated by different methods. In the process of dressing, we should make the shape of hoof suitable for limb position as far as possible, trim the tip of hoof more, and pay attention to the bottom of the hoof, to ensure that the hoof is in a natural physiological state after dressing.
Strengthen feeding management. Rational feed mix, especially for high-yielding dairy cows, should timely adjust the proportion of protein and minerals in feed according to the actual milk production, and appropriate supplementation. As long as it is found that the shape of the hoof begins to change, a proper amount of vitamin D3 can be injected in time, and a proper amount of calcium powder can be added to the diet. The ratio of calcium to phosphorus should be controlled at 1.4:1. Also, regular addition of 0.01%-0.02% zinc sulfate to the diet of dairy cows, each continuous use of 1 month, a total of 5 times a year, can effectively avoid the occurrence of foot and limb disease.
For high-yielding dairy cows with primipara, management should be strengthened. This is because primipara dairy cows are more prone to disease when they produce too much milk (up to 6000 kg), so they can not adopt partial feeding and blindly pursue high yield. If dairy cows are stretched and bowed due to high yield, they can stop milk suitably in advance, otherwise, it is very easy to cause hoof deformation. The stadium should ensure good drainage. It can be convex with lower circumference and slightly higher middle, which is conducive to drainage and seepage. To avoid the cow's feet being soaked in urine, dung, and dirt, the cowshed and combed must be kept clean, dry and well ventilated, and the cow's feet should be washed regularly. In general, wet brushing should be adopted in summer, dry brushing in winter and timely cleaning of the stadium. Every year, cattle should conduct a general survey of hoof shape and formulate a reasonable hoof-trimming system. Breeding of breeding bulls should be strengthened and detailed pedigree files should be established to avoid the formation of hereditary hoof deformation.
Foot disease of dairy cows is a common disease in dairy production, which causes lameness of dairy cows and paralysis of dairy cows. If we do not pay attention to it, it will increase production costs and reduce economic benefits.
The shape of the finger hooves has changed. Because the shape of hoof deformity is different, it can be divided into three kinds: long hoof, wide hoof and rolled hoof.
(1) Etiology
①The unbalanced diet and inadequate or inappropriate supply of calcium and phosphorus in mineral feed lead to disorder of phosphorus and calcium metabolism and imbalance of calcium and phosphorus ratio in dairy cows, resulting in foot deformation.
②Foot deformity has a certain relationship with the milk production of dairy cows. Generally, cattle with high yield per unit area have a higher incidence. The main reason is that in order to pursue milk production, farmers excessively increase the feed of concentrate in the feed, too little feed is taken, the quality is too poor, and the proportion of concentrate and coarse feed is inappropriate, which makes the body of dairy cows in acidosis for a long time, causes inflammation of hoof leaves and leads to deformation of hoof.
③Improper feeding and management. The cowshed is dark and humid, the stadium is muddy, the excrement and urine cleaning is not timely, and the hoof of cattle is immersed in excrement and urine for a long time, which makes the hoof horn soft and deformed. In production, the protection of cattle hooves is neglected and irregular pruning can easily lead to Hoove deformation.
④Hoof deformations are related to the heritability of bulls. If bulls have congenital hoof deformity, offspring are also highly susceptible to the disease.
(2) Symptom
Long hoof: that is, extending hoof, the two side branches of the finger hoof exceed the length of the normal hoof branch, the corneum of the hoof extends forward excessively, and the appearance is long.
Wide foot: The length and width of both side branches of the hoof are longer and wider than those of the high normal hoof, and the appearance is large and wide, so it is also called "big limb plate". This kind of hoof has a thinner cuticle and lower heel. When standing and running, the front edge of the hoof is not loaded properly. It is not suitable to turn up slightly and return.
Rolling hoof: Rolling of the sole of the medial or lateral branches of the hoof. Looking from the bottom of the hoof, the outer edge is excessively worn, the back of the hoof has turned into the bottom of the hoof, the corneum of the fork of the hoof becomes thicker, wears out incorrectly, and the bottom of the hoof is unevenly loaded. Often, the lower tarsal joint of the hind limb inclines outward, showing an "X" shape. The severely diseased cattle stretch their hind limbs backward, and the diseased cattle have difficulty in bowing back and running. They are dragging type, which is called "turning over their feet, shining their feet and stretching their feet".
(3) Diagnosis
According to the clinical manifestation, i. e. the deformity of the hoof, the diagnosis can be confirmed.
(4) Prevention and Treatment
Drug therapy can not make deformed hoof return to normal. In the clinic, hoof repair therapy is often used. Corresponding methods are adopted according to the degree of hoof change. Therefore, the key to prevent and cure the disease is to do a good job of prevention. In production, attention should be paid to strengthening the feeding and management of dairy cows, and the supply of protein and minerals should be paid full attention to. According to the lactation status of dairy cows, the rational formulation of diets, especially high-yielding dairy cows, should be adjusted and supplemented at any time according to their milk production. Once the hoof shape begins to change, vitamin D3 can be injected into the diet, supplemented with calcium powder to prevent its deterioration. The positive balance of phosphorus and calcium metabolism can be obtained at a ratio of 1.4:1.
At the same time, attention should also be paid to regular hoofing of dairy cows. To prevent the foot from being impregnated by dung, urine, and dirt, it is necessary to keep the foot clean (dry brushing in winter and wet brushing in summer). The stadium should be cleaned and kept dry in time. The foot shape of the whole herd should be checked every year and a regular hoof repair system should be established. All deformed hoofs are trimmed once or twice a year. To prevent infection of cattle hooves, Hoove repair should not be carried out in a rainy season. Effectively strengthen the breeding of breeding bulls, to investigate the deformations of cow's hooves related to the bull, we can consider not using the bull breeding.
preventive measure
Foot disease is one of the four most common diseases in dairy cows. To improve people's lives, develop the dairy industry and achieve the goal of healthy, high yield and long life of cattle, comprehensive prevention, and control of foot disease which seriously endangers dairy cow production must be carried out. In the prevention and treatment of foot disease, we must carry out the policy of "prevention is more important than treatment, combining prevention and treatment", and formulate a set of measures according to the specific conditions of each field.
(1) Feeding
Balanced diet: According to the different stages of lactation, dairy cows are fed in groups. According to the nutritional allocation of various diets that meet the needs of dairy cows, it is particularly important to pay attention to the technology of Ration Compound for Dairy Cow and the proper proportion of concentrate and roughage, and the high quality of crude material is necessary for dairy cows. The quantity of calcium, phosphorus, magnesium, potassium, sodium, and sulfur in feed must be guaranteed, especially the quantity of calcium and phosphorus and the appropriate ratio of calcium to phosphorus; the number of trace elements iron, copper, manganese, zinc, cobalt, selenium, and iodine must be guaranteed; the balance of anion and cation in diet should be paid attention to. It is necessary to ensure the supply of vitamin A, D, E and nicotinic acid in dairy cattle. To ensure the pH value of rumen cattle between 6.2 and 6.5, a buffer can be added to prevent lactic acid poisoning and increase the stimulating intake.
(2) Management
Cleaning up the environmental hygiene of dairy farms and keeping the playground and cowshed clean and dry can effectively prevent the occurrence of foot disease. Because the high ammonia content can increase the moisture content of the hoof horn, soften the horn, and reduce the resistance of hoof to various injuries. Daily cattle dung and sewage should be cleared in time in cowshed and playground, stones and hard objects in playground should be cleared in time to prevent foot contusion; fresh-hoofed cows should not move on the cement floor in the first two weeks; there should be lines on the cement floor; too smooth cement floor can easily cause skidding and damage to cow's hoofs.
The design of the cowshed must be reasonable. 85% of dairy cows in scattered cowshed should sleep on the cow bed after feeding. There should be enough dry and clean mattress on the cow bed. The rest time of dairy cows should also be maintained for more than 4 hours because the clean and dry cow bed can reduce the incidence of bacterial reproduction and hoof disease. To effectively prevent infectious hoof disease and increase the hardness of hoof horniness, insist on 2 times a week to give the cow a hoof, choose a 4% copper sulfate bath with little irritation and no smell, spray the liquid into the hoof of the cow directly with plastic sprayer.
When spraying hoofs, cattle dung, and soil cushion should be swept away so that all the medicinal liquid can be sprayed on the roof shells. In the corridors of milking platforms and cattle ranches, where conditions permit, a 5-meter-long, 3-meter wide and 10-centimeters deep medication bath should be constructed to allow cows to walk on stage during milking and grazing to achieve the purpose of immersion, but the medication bath must be replaced regularly so as not to become a "cow manure urinary tank". Also, regular hoof repair is an important measure to prevent hoof disease.
4. Treatment of foot disease
Any measures taken to treat foot diseases are based on accurate diagnosis. The condition and location of foot disease should be determined according to the clinical symptoms of dairy cows and through diagnostic procedures such as inquiry, visitation, palpation, and various special examinations. No matter what kind of old disease is treated, first, clean the foot thoroughly, remove the dirt of the foot with water and brown brush, hoof knife, and then make necessary repairs to the foot disease, fully expose the affected parts, and thoroughly disinfect the affected foot before implementing the treatment measures.