Anestrus is a broad term that indicates the lack of oestrus expression at an expected time.
Anestrus is a functional disorder of the estrous cycle that is characterized by the absence of clear signs of estrus manifested either due to lack of expression of estrus or failure of its detection.
Anestrus in presence of functional CL (Apparent Anoestrous)
•Anestrus due to pregnancy.
•Anestrus due to pyometra.
•Anestrus due to mummified foetus.
•Anestrus due to macerated foetus.
•Silent heat or weak heat.
Anestrus in absence of functional CL (True Anestrous)
`•Chronic wasting disease
•Delayed puberty – due to undernutrition.
•Abnormal reproductive tract – Freemartins, hermaphrodites,
•Segmental aplasia of paramesonephric duct and ovarian hypoplasia (incomplete development of ovary) .
•Debilitating disease such as chronic pneumonia etc. •
When a heifer attains two-third of its adult body weight, she is ready for mating and to go through pubertal stages.
•Physiological anoestrus for 2-3 weeks after parturition.
•Nutritional stress such as decreased body energy level and deficiency of vital amino acids or micro minerals.
•Reproductive diseases such as retention of fetal membranes (RFM), metritis, pyometra, etc.
•Chronic debilitating diseases such as leg injuries, displaced abomasum or hardware disease.
•Silent oestrus (the condition in which behavioural signs of the estrous are not exhibited.)
•Progesterone Level Estimation
•Per Rectal Examination
Treatment of true anoestrus
1. Deworming with appropriate drug for emaciated animals e.g. Albendazole, Fenbendazole etc.
2. Offer mineral mixture or supplement for one month.
3. Phosphorus injection 10 ml. intramuscularly for three days.
4. Gentle ovarian massage and painting of external os with Lugol’s iodine on alternate day three times.
Lugol iodine causes local irritation on cervix and stimultes anterior pituatry for the production of gonadotrophins which ultimately helps in ovarian cycle.
1. Administration of GnRH analogues :
Brand names available in Pakistan.
2. Administration of eCG or PMSG:
• Equine chorionic gonadotrophin is widely used gonadotrophic drug in cattle.
•It can be used to stimulate ovarian activity and can induce follicular growth and oestrus within 2-5 days.
•Folligon by intervet (1500 – 3000 i.u. I/M)
3. Administration of progesterone:
•Intravaginal route of administration of progesterone gives the most favorable result. PRID or CIDR device is placed in anoestrous cows for 7-14 days. Removal of this device produces estrous signs in most of the animals. After removal of the device, a sudden decline of progesterone occurs. The external source of progesterone mimics the luteal phase of the estrous cycle. So, when device is removed, new ovarian cycle starts.
Treatment of silent heat
•Inject anyone PGF2α analogue when active CL remain present and do double AI after 48-72 hrs.