Silent estrous is a serious problem in animals which are productive in purpose.
In this condition animal will not show behavioral signs of estrus although the physiological symptoms of heat are present.
Silent heat and its management;
- Synonyms:
Sub estrus
Silent heat
Quiet ovulation
- Introduction:
Ovulations occur without behavioural manifestation of estrus. The first and second ovulation postpartum are often not preeced by behavioural signs of estrus and are thus are truly ‘Silent heats’.
In heifers, the estrus associated with first ovulation is usually silent.
In this condition animal will not show behavioral signs of estrus although the physiological symptoms of heat will be present.
Although the general pattern of sexual behavior is almost similar in cattle and buffaloes but the intensity of expression of behavioral signs of estrus in buffaloes is markedly less pronounced especially during summer months as the buffaloes are relatively inefficient to maintain their thermoregulation under increased environmental temperature and at high relative humidity
So due to this reason buffaloes are in constant heat stress during summers which causes the suppression of behavioral signs of estrus.
In addition to this the other behavioral signs of estrus such as mounting to fellow animals and allowing other animals to mount, restlessness may also be expressed in much diminished intensity.
In addition to this the other behavioral signs of estrus such as mounting to fellow animals and allowing other animals to mount, restlessness may also be expressed in much diminished intensity.
- Causes:
A sub threshold of hormone production or an imbalance between hormones
Nutritional defficiencies such as defficiency of ß Carotene, Phosphorous, Copper, Cobalt etc
- Diagnosis:
Diagnosis is based on
clinical history
rectal palpation of the genital system.
- Management:
This problem can be overcome by removing different constraints such as allowing animals for grazing or left them loose for few hours where the animals have been tied.
There should be provision of non-slippery or kuccha floors to facilitate the mounting activity of the cows that are in estrus
In summer season water should be sprinkled over the body of the animals for 5-10 minutes twice or thrice daily or allow them to wallow for two hours daily in the morning and in the evening to alleviate the impact of heat stress
At large organized dairy farm mistress cooling system installed inside the shed is found to be very effective in maintaining normal estrus behavior of buffaloes and cross-bred cows.
If the roof are made up of asbestos or iron sheet then spread some paddy straw over it make wet by sprinkling of water.
Animal should be fed green fodder and the feeding must be done during cool hours of the day.
During summer the feed intake of the animal is reduce so the quality of the ration should be improved in order to fulfill their physiological needs.
In addition to this there should be improved or efficient methods of heat detection.
A combination of methods is better than relying on a single method of heat detection.
- Treatment:
If a mature Cl is present, PGF2α or an analogue followed by Timed Artificial Insemination (TAI) can be carried out. If a CL is at refractory stage, double injection PG regimen at 11 days interval could be used.
Alternatively PRID or other progesterone implants could be used folllowed by fixed time insemination
Visual observation should be performed by trained persons during cooler hours of the day especially during early morning and late evening as the behavioral signs of estrus are more pronounced during this period.
Parading of teasure /vasectomized bull during early morning and late evening.
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