Related party transactions - Summary of Transactions Due To Related Parties (Detail) - CNY (¥) ¥ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Nanjing Animal Pharmaceutical [Member]
Schedule Of Transactions Due To Related Parties [Line Items]
Trade payables to related parties	¥ 471	¥ 219

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant