How many {animal breed} are to/by {Arabian horse} ?
Which is the number of the breeds that are for Arabian horse?
How many breeds of Arabian horse are there?
SELECT ( COUNT ( ?i ) AS ?z ) { ?i property:animal_breed resource:Arabian_horse }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P4743> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q184138 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P4743 wd:Q184138 }
20