Use of diagnostic imaging in dairy animals key to profitable farming

Pakistan’s economy is based on agriculture which is contributing around 20 per cent to the GDP. Livestock is considered the backbone of agriculture as it accounts 58 per cent of its share.

It plays a vital role in national growth, food security and poverty alleviation. On the other hand, increasing human population in Pakistan has led to increased demand for consumable foodstuffs such as vegetables, fruits, meat and dairy products.

Dairy farming plays an important role, as it not only meets the protein requirement for humans but also necessary for the economic reason due to the cash produced from the sale of milk.

Pakistan is the 6th largest milk producer in the world due to rise in number of milk producing animals, not due to the increase in per animal production. Pakistan’s dairy farming system is diverse and consists of rural subsistence, rural commercial, periurban, commercial and corporate.

During the last two decades, their trend is changing from subsitence to commercialization. Paradoxically, in order to cope up this gap, Pakistan is importing powdered milk and on the other hand approximately has imported more than 100,000 exotic cows having high milk production from developed dairy countries.

One of the disadvantages of the exotic cows is that they lose their high productive and reproductive ability due to poor adaptation to the local environment and management.

In this situation our local dairy animals can better thrive to these environmental conditions but their production and reproduction is slow due to poor selection.

Therefore, Pakistan dairy industry is growing and commercializing rapidly to manage with escalating demand for milk and other foodstuffs.

Better reproductive management is key to improving farm profitability by decreasing the number of days after calving, thereby increasing the milk productivity and decreasing the cost of feeding and management. For profitable dairy farming each cow must give birth to a calf in a year. It is now established that during past few decades in exotic cows reproduction has become much more challenging ever since there has been increased selection for higher milk production.

Nowadays it is possible to use advanced reproductive technologies like estrus and ovulation synchronization and optimum time of artificial insemination. In order to have effectiveness in these technologies, use of ultrasonography has become mandatory. Early and reliable detection of pregnancy are bottleneck for future of dairy farm profitability.

Different methods are practiced for the reliable and efficient diagnosis of pregnancy which include rectal palpation, hormonal assay, pregnancy specific proteins, B-mode and Doppler ultrasonography.

All these methods have their own merits and demerits. Rectalpalpation which is conventional method for diagnosis of pregnancy around 60 days is fairly simple and accurate but late. Ultrasound can efficiently detect embryo heart beat around 25 days.

It is used for the reproductive management that is early diagnosis of pregnancy which results in overall farm fertility and pathological condition like ovarian cysts.

Newer form of ultrasound is color Doppler which can detect blood flow and predict pregnancy around one week after mating or artificial insemination.

These observations were made in experiments on native Sahiwal cows in a research project sponsored by Pakistan Agriculture Research Council at Department of Theriogenology of University of Veterinary and Animal Sciences in collaboration with University of Zurich, Switzerland. Development of color Doppler ultrasonography extended the scope of sonographic imaging from an anatomical to a physiological basis.

Doppler ultrasonography is a recent technique which is being used in humans for diagnosis of different arterial complications but in dairy animals it is used for detection of maternal and fetal abnormalities and prediction of successful pregnancy on basis of blood flow to reproductive organs dominant follicle and corpus luteum.

This is the first study ever in Pakistan on Sahiwal cows to determine the reproductive physiology by using Doppler ultrasonography. The blood flow of uterine artery is more at the time of estrus and ovulation concurrent with the concentrations of estradiol hormone.

The blood flow is dependent on the concentrations of hormones. Therefore, the blood flow to ovaries is an excellent indicator of early pregnancy diagnosis in cows. Early pregnancy detection is more profitable in dairy industry by saving time in non-pregnant animals. In this way we can hasten reproductive management by applying pre-synchronization, synchronization and re-synchronization protocols for the induction of estrus, ovulation and early re-insemination.

This approach can save time, money in terms of cost of feeding and management which resulted in increase in the production per cow by decreasing the days open, obtaining calf every year and achieving the goal of reproduction of ‘a calf a year’.

In summary, use of modern reproductive technologies and imaging system can be potentially very useful in enhancing profitability of dairy farming.