India is the world's second largest beef exporter and fifth biggest consumer, although its majority Hindu community views cows to be sacred, and Modi's BJP is pushing for legal steps to "protect and promote the cow".
Maharashtra, which has a population of about 110 million, and sprawls over an area roughly the size of Italy, widened its ban this month to cover meat from bulls and bullocks. The states of Jharkhand and Haryana, also ruled by the BJP, are looking for ways to discourage slaughter of livestock.
Such curbs, which critics call the outcome of Modi loyalists pushing a Hindu agenda, will cost jobs and hit India's exports, but spell good news for many poultry farms. India consumed 2.3 million tonnes of beef last year until October -- higher than for the whole of 2013 -- while exports were 1.95 million tonnes in the same period.
"We are expecting chicken consumption to increase in Maharashtra after a month, as it is a direct alternative to beef," said Prasanna Pedgaonkar, deputy general manager at chicken processor Venky's.
Pedgaonkar expects the measure to push up sales 5 percent for his firm, which owns the English football club Blackburn Rovers, from a daily figure of 1,500 tonnes now.
Overall consumption in the state could rise 5-8 percent within a month, said Dinesh Bhosale, the South Asia sales head of AB Vista, an animal feed supplier based in Britain.
Even without a ban on beef, which is particularly popular in the southern and northeastern parts of India and tends to be cheaper than mutton and chicken, India's poultry output has been scaling annual records, as higher incomes boost demand for meat in the world's second-most populous country.
Broiler production will hit a new high of 3.9 million tonnes in 2015, the US Department of Agriculture estimated in October.
Owners of Mumbai shops that sell chicken say the effect of the beef ban has yet to show up in prices, although demand is starting to pick up despite the onset of summer, when consumption usually slows.
"Usually (demand and prices) drop during summer months, but this year they may not, due to the ban on beef," said Abdul Azar, as he cleaned his small chicken shop.