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I am pleased to offer this edition of “Common Reproductive Disorders in Cattle; Farmer’s Guide” as an easy and comprehensible guide for dairy farmers. It covers many aspects of different reproductive diseases commonly found in dairy cattle related to infertility with practical information for farmers. Improving fertility is a common goal for dairy herds or livestock owners and getting cows pregnant in a timely manner is important in maintaining a profitable dairy business. Scientific management of dairy cattle is indispensable for achieving optimum reproductive efficiency and to reduce losses due to various reproductive diseases leading to infertility as infertility is one of the major causes for economic loss to farmers and making dairy farming economically unviable. Therefore, it is of utmost importance to manage the most probable causes leading to reproductive failures in cows with early intervention in order to reduce their economical impact in dairy cows and this can be possible through improving the knowhow of the farmers concerned with rearing of cattle as is expected with the help of this book.

A cow is called repeat breeder when it has failed to conceive even after three or more number of services, has normal estrus cycle length, no abnormal vaginal discharge, no palpable abnormality in the reproductive tract, has calved at least once before and is less than ten years of age. Repeat breeding is one of the most important infertility problem faced by field veterinarians. Causes 1) Fertilization failure 2) Early embryonic death Main Points that Need to be Known by a Farmer About Repeat Breeding Cow • Signs of estrus like vaginal discharge and its color, bellowing, mounting etc • Time of estrus as observed by owner (morning, evening etc) • Vaginal discharge whether clear or mucopurulent/purulent • Duration of estrus • Inter-estrous interval • Number of inseminations

Anoestrus in cows is a condition in which there is absence of observable estrus signs. Anoestrus in cattle is suspected when estrus in not expressed by the female animal or in case the farmer fails to detect it. Among reproductive problems, it is one of the most commonly occurring conditions in cattle. It affects the production and economics of a cow to a great extent and the economic losses occur due to increase in inter-calving interval, poor net calf crops, loss of production, expenses incurred on treatment etc. It is caused by multiple factors including mostly inadequate or unbalanced nutrition, environmental stress, uterine or ovarian pathologies and poor managemental practices. Diagnosis • Rectal examination of animal. The ovaries are small and smooth. Should be confirmed by repeated examinations at 10 days interval. • Ultrasound examinations at regular intervals can be done to diagnose and confirm anestrous. • Progesterone estimations at intervals of 10 days would aid in confirmation. Low progesterone levels at both times indicate true anestrous.

Sub estrus (Weak or Silent Estrus) is a condition in which there are normal cyclical changes in the reproductive organs of a cow but the heat signs are not exhibited to a level of intensity as in normal cows leading to failure of estrus detection by a farmer. This condition is common during post partum period. It is a common reproductive problem in cattle affecting the productivity and economics of a cow due to increase in inter-calving interval, production loss, treatment expenses etc.

In subclinical endometritis (SCE), there is inflammation of the internal lining of uterus (endometrium). It is one of the major causes of repeat breeding in cattle and causes significant reduction of reproductive performance. Cervico- vaginal mucus in subclinical endometritis is clear in contrast to endometritis. It is also called cytological endometritis and is associated with increased proportion (percentage) of polymorphonuclear cells (PMN) in endometrial cytology samples. SCE affected cows have delayed first service and subsequent pregnancy causing significant economic losses due to reduction in reproductive performance, feed intake increase per lactation, milk yield reduction and increase in culling rate.

Endometritis in cow is actually the inflammation of endometrium that is inner lining of the uterus. It occurs after bacterial contamination of uterus at calving, during A.I. following dystocia, retention of placenta, abortion etc. There is expulsion of white or whitish-yellow muco-purulent discharge from vagina. The animal does not shows systemic signs like increase in temperature, increase in respiration rate, anorexia, toxemia etc as in metritis. However, the animal fails to conceive even after repeated inseminations.

Metritis is a condition seen in cattle in which there is the inflammation of the entire thickness of uterine wall (endometrium, myometrium and serosa). When it occurs just after parturition, it is called puerperal metritis. It usually occurs after abnormal birth like in case of dystocia, abortion, RFM etc. The animal shows systemic signs like increase in temperature initially, increase in respiration rate, anorexia, toxemia etc. There is expulsion of large volume of foul smelling reddish to brown discharge from vagina frequently associated with straining. The expelled discharge from vagina is often with pieces of degenerating placenta.

Retained fetal membrane (RFM) in cow is a condition in which fetal membranes or placenta fail to separate and expelled by 12-24 hours after the birth of calf. It is a common in bovines and is usually associated with dystocia, abortion etc. Retained placenta in bovines predisposes the animal to uterine infection and thereby leads to infertility.

Vaginal prolapse in cow is a condition in which there is protrusion of whole or part of vagina including sometimes the part of cervix through the vulva. It occurs in cow mostly during last 2-3 months of gestation. It occurs due to excess secretion of estrogen from placenta, hypocalcaemia, inadequate exercise, bulky food like roughages etc. Sometimes occurs in non pregnant cows due to cystic ovaries, severe straining due to vaginal irritation etc.

Uterine prolapse also called casting of the “Calf Bed” in cow is a condition in which there is eversion of whole or part of uterus outside the vulva after its movement through dilated cervix and vagina. It occurs in cow after the birth of calf and mostly in dairy cows having given birth many times to a calf. It occurs due to hypocalcaemia, defective involution, inadequate exercise, excessive force applied during removal of calf etc.

Pyometra meaning “pus filled uterus” is a condition in cow which is characterized by progressive accumulation of pus in the uterus, presence of persisting CL, absence of estrus and regular estrus cycles and a closed cervix. Pyometra occurs following chronic endometritis in most cases as uterus fails to produce endogenous CL regressing agent i.e. PGF2a. So, the CL of diestrus persists resulting in failure of elimination of uterine infection as the animal remains under the continuous influence of progesterone. Progesterone production from the persistent CL causes closure of cervix, pus accumulation in the uterus and consequently leading to enlargement and distension of uterus.

Uterine torsion in cow is actually the rotation of the pregnant uterus on its longitudinal axis and usually occurs before onset or during late first stage of parturition but rarely encountered during early second stage of parturition. In cattle, uterine torsion involves both gravid and non gravid horns because of strong intercornual ligament and distension of uterine horn and body with placenta and fluid. The remarkable feature of uterine torsion is its association with advanced pregnancy and process of parturition in cow.

Cystic ovarian disease (Cystic ovarian degenertaion or ovarian cysts) is a common ovarian dysfunction in cattle and causes huge economic loss to farmers due to its high incidence and negative impact on the reproductive performance of cow. Animals having cysts on ovary result in anoestrum as the most significant clinical sign. Althouugh the exact cause that leads to cystic ovarian disease is not yet fully clear but altered release of LH hormone is the most accepted hypothesis.

Estrus is referred to as the period of estrous cycle during which the female animal allows the male for mating. It is the period of estrous cycle during which insemination is done to female animal so that the animal will become pregnant. During estrus, cow usually seeks out the male and ’stands’ for him to mate her. In all domestic species, Ovulation occurs during this phase of the cycle but in case of cow, ovulation occurs about 12 hours after the end of estrus period.

Artificial insemination (AI) is a technique in which sperm cells loaded in straws and stored in liquid nitrogen are thawed and manually deposited into the reproductive tract of a female animal at estrus. The recto-vaginal technique is the most commonly used method for artificial insemination in cattle. In order to increase the probability of pregnancy, the animal in estrus should be inseminated at proper time not too early or late.

The diagnosis of pregnancy (Cyesiognosis) was desired earlier by farmers for curiosity, but currently early pregnancy diagnosis is considered essential for economically viable and profitable dairy farming. Clinical methods are commonly used for pregnancy diagnosis in cattle with recto genital palpation and trans-rectal ultrasonography as the methods of choice for an accurate and early pregnancy diagnosis.

Vaccination of cattle and prevention of diseases causing huge economic losses is very much essential for economic rearing of livestock as prophylactic and strategic vaccination helps in development of immunity against the vaccinated diseases thereby prevents the animals from developing such infections and consequent diseases. Animals should be vaccinated at specific age and at definite time intervals for optimal protection against the diseases.

Regular deworming of cattle including young stock is essential for economic rearing as sever parasitic infection leads to reduced feed intake, decreased reproductive performance, lower milk production, decreased growth rate and increased incidence of diseases. So, deworming as per scientific schedule and dose rate is a must for animals to keep away these profit eating parasites.

Calves play an important role in the dairy development and successful growth of young calves to mature stage is required for herd replacement and to get economic returns when they are sold. Good calf-care is important for sustenance of the dairy form and preservation and maintenance of good quality germplasm.

Maintenance of optimum fertility and reproductive goals is very important for profitable and economically viable cattle rearing. It is highly desired and essential for the farmers to maintain the high reproductive efficiency in cows so that the losses incurred on infertility are reduced to the maximum extent through good managemental practices and following scientific guidelines properly.