( However ( , ( ( after ( the ( first ( postpartum ovulation ) ) ) ) ( , ( ( some cows ) ( ( have ( ( a ( ( short estrous ) cycle ) ) ( -LRB- ( ( ( ( ( 9 to ) 15 ) days ) ( in length ) ) -RRB- ) ) ) ) . ) ) ) ) ) )
(ROOT (S (ADVP (RB However)) (, ,) (PP (IN after) (NP (DT the) (JJ first) (NN postpartum) (NN ovulation))) (, ,) (NP (DT some) (NNS cows)) (VP (VBP have) (NP (NP (DT a) (ADJP (RB short) (JJ estrous)) (NN cycle)) (PRN (-LRB- -LRB-) (NP (NP (QP (CD 9) (TO to) (CD 15)) (NNS days)) (PP (IN in) (NP (NN length)))) (-RRB- -RRB-)))) (. .)))
However, after the first postpartum ovulation, some cows have a short estrous cycle (9 to 15 days in length).
(ROOT (S (NP (NNP Ovulation)) (VP (VBZ occurs) (SBAR (IN before) (S (NP (DT the) (NN endometrium)) (VP (VBZ thickens) (PP (IN in) (NP (JJ estrous) (NNS cycles))))))) (. .)))