( ( In ( ( extremely unbalanced ) herds ) ) ( , ( ( ( the majority ) ( of adult ) ) ( ( does ( ( may not ) ( be ( bred ( during ( their ( ( ( first estrous ) ( -LRB- ( ( period ( of ( ovulation ( and ( sexual receptivity ) ) ) ) ) -RRB- ) ) ) cycle ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (ADJP (RB extremely) (JJ unbalanced)) (NNS herds))) (, ,) (NP (NP (DT the) (NN majority)) (PP (IN of) (NP (NN adult)))) (VP (VBZ does) (SBAR (S (VP (MD may) (RB not) (VP (VB be) (VP (VBN bred) (PP (IN during) (NP (PRP$ their) (NP (NP (JJ first) (NNS estrous)) (PRN (-LRB- -LRB-) (NP (NP (NN period)) (PP (IN of) (NP (NN ovulation) (CC and) (JJ sexual) (NN receptivity)))) (-RRB- -RRB-))) (NN cycle))))))))) (. .)))
In extremely unbalanced herds, the majority of adult does may not be bred during their first estrous (period of ovulation and sexual receptivity) cycle.
(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))))))) (. .)))