He deals in an’aam animals and in some cases one full hijri year has not yet passed. How should he pay zakaah on them?

Firstly: 

The majority
of scholars are of the view that no zakaah is due on an’aam animals (i.e.,
camels, cattle, sheep and goats) unless they graze freely on grass in the
pasture and one full hijri year has passed for all of them or most of them.
But if they are fed and their owner spends money on their feed, no zakaah is
due on them, unless their owner intends to trade in them – as is mentioned
in your question – in which case they are subject to the zakaah on trade
goods. 

So these
goats that you have are not subject to the zakaah on an’aam animals, rather
they are subject to the zakaah on trade goods. 

See more
details in the answer to question no.
40156. 

Secondly: 

It should be
noted that some people make a mistake with regard to the beginning of the
year for zakaah. They think that it is the moment when they buy the trade
goods, but that is not correct. Rather the year for trade goods is when the
year from when one acquired the money with which one buys them has passed,
if that money reaches the nisaab (threshold). 

What this
means is that if a person buys trade goods – such as goats that are fed etc
– with gold or silver or cash that reaches the nisaab, then the year starts
from the time when he took possession of that gold or silver or cash.
Similarly, if he buys goats in return for a car that he trades, the year for
the goats is the year from when he acquired the car. 

The reason
for that is that in trade you buy and sell, and exchange money or goods, and
if the year is not based on the wealth which came before, there would be no
zakaah on trade goods. 

Shaykh Ibn
‘Uthaymeen (may Allaah have mercy on him) said, explaining this issue: If a
person buys trade goods with money that reaches the nisaab, such as a man
who has two hundred dirhams, and during the year he buys trade goods with
it, the year does not start when he buys the good, rather it is based on the
first, because the year for trade goods is to be based on the first. 

Another
example is if a man has one thousand riyals of which he takes possession in
Ramadaan, then in Sha’baan of the following year he buys some trade goods.
When Ramadaan comes, he must pay zakaah on those trade goods, because the
year for trade goods is based on the year for the money with which they are
bought. 

The same
applies if he trades goods that reach the nisaab for other goods. For
example, a man has a car, and during the year he trades it for another car
for the purpose of trade. The year should be based on the first car, because
what is sought is its value, not the difference in the two products, and he
did not buy the second car to use it, rather he wanted it so that he could
trade it. End quote from al-Sharh al-Mumti’. 

Based on
this, if you took possession of ten thousand, for example, in Ramadaan, then
you bought goats with it in Dhu’l-Hijjah, and you started to sell them or
their offspring, and buy others, the year for zakaah is in Ramadaan. You
have to work out the value of the goats that you have each year, then add to
that the cash that you have, and pay zakaah on the total at a rate of
one-quarter of one-tenth.  The year for zakaah will continue to be in
Ramadaan unless the amount falls below the nisaab during the year, such as
if a person sells what he has in Safar, for example, and he puts the money
into buying land or a house to live in, then Allaah blesses him with wealth
during Rajab, so he buys more goats to trade. Then the year for trading will
start in Rajab. 

And Allaah
knows best.