The love between farmers and their cows is legendary.
Take Sarat Chandra Chattopadhyay's famous tale, later set to music by Bhupen Hazarika, of poor peasant Gafoor Zola and his bull Mahesh: Gafoor is so ridden with guilt after beating his loyal bull to death during a period of severe want that he abandons farming altogether.
During Eid-ul-Azha, this prized possession is offered as a sacrifice in commemoration of Hazrat Ibrahim's (AS) test of faith.
The bond that farmers develop with their cattle makes the eventual slaughter of their animal no easy task. As livestock, the contribution of cattle to the economy is immense.
But cows are domestic animals and trusty members of the rural household. For the farmer who reared the animal, the loss of a cow, though paid for in cash, is in a sense incalculable.
The usefulness of cows begins in the womb – mother cows start producing milk when they are pregnant.
This milk provides farmers with a daily source of income and nutrition.
During their lives, oxen or bulls pull ploughs through paddy fields. Dung is used as fertiliser, as a house-cleaning agent and as fuel in the kitchen.
The animal's urine is used as an anti-bacterial agent in crop and vegetable fields.
Even after they die, cows keep on giving.
Cattle bones, hooves, horns, tails and even penises are in demand for their commercial value.
According to the Export Promotion Bureau, in fiscal year 2014-15, Bangladesh exported animal guts, bladders and stomachs worth a staggering $14.71m (over Tk114 crore). That same year, the export of cattle bones and horns fetched $3.38 million (over Tk26 crore).
Hard substances such as teeth and bones are cut with machines to uniform sizes and sold. Local pharmaceutical companies use these to make the shell of capsules while some are exported. Hooves and horns are also exported and used for making combs, buttons and X-ray films.
Cattle ears are boiled and dried in the sun, ground into powder and sold to poultry feed traders. Bone dust is also mixed with poultry feed and fertilisers.
The leather industry, Bangladesh's second largest export revenue earning sector, thrives on the cattle hide collected during Eid-ul-Azha every year. According to the Export Promotion Bureau, the export of leather and leather goods crossed $1 billion in 2014-15 for the second year in a row.
Data from the Board of Investment of Bangladesh shows that milk production is one of the most important economic activities in Bangladesh, providing 3.6 million households with supplementary income.
There are very few Bangladeshi desserts that do not contain milk. It is de rigour to serve a sweet milk-based dessert at family get-togethers, festivals, and even the sharing of good news.
Cow fat is used in the making of soaps and detergent, in addition to being a secret ingredient in making rich parathas. People on a budget use it in place of ghee to make dishes more savoury.
Last but not least is the beef itself – the most popular red meat in Bangladesh. It would be very hard to find even one Bangladeshi Muslim family that does not have beef stored in the refrigerator. In rural areas where refrigerators are uncommon, the meat is dried in the sun to preserve it.
Different areas have their own distinct varieties of beef curry – Mezbani beef in Chittagong, Shatkora beef in Sylhet and the famous Kala Bhuna of Old Dhaka are among the most popular.
Kebabs made of beef, the Mughal empire's gift to Bangladeshi cuisine, are very popular. According to unofficial counts, there are several hundred kebab restaurants in Dhaka.
Rooftop barbecue parties in urban areas, a recent tradition during the Eid-ul-Azha holidays, have gained in popularity among the younger set.
With the estimated 5 million hoofed animals, including cows, slaughtered this Eid-ul-Azha, the myriad products derived from the cow are plain to see.
Farmers will make some money and receive a measure of meat during the festival, but they will have lost a farm animal whose value is undeniable.
Throughout their lives and beyond, cows are dependable livestock that engender a kind of loyalty.
Echoing the reliance that Gafoor came to feel for his hapless bull, food policy expert Joan Gussow says: “As for butter versus margarine, I trust cows more than chemists.”