Domain/range axioms redundancy

Hi,Please I wonder to know if it is correct to say "that domains and ranges could not be redefined for sub-properties? This is because sub-propoerties inherit their domains and ranges from superproprties?Indeed, what I found in the univ-bench ontology is that domain and range axioms for mastersDegreeFrom property are re-asserted though they are alrady asserted for the super-property degreeFrom? are not they a form of repetition? could not they be entailed?

    <!-- http://swat.cse.lehigh.edu/onto/univ-bench.owl#degreeFrom -->
    <owl:ObjectProperty rdf:about="http://swat.cse.lehigh.edu/onto/univ-bench.owl#degreeFrom">        <rdfs:label>has a degree from</rdfs:label>        <rdfs:domain rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#Person"/>        <rdfs:range rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#University"/>        <owl:inverseOf rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#hasAlumnus"/>    </owl:ObjectProperty><!-- http://swat.cse.lehigh.edu/onto/univ-bench.owl#mastersDegreeFrom -->
    <owl:ObjectProperty rdf:about="http://swat.cse.lehigh.edu/onto/univ-bench.owl#mastersDegreeFrom">        <rdfs:label>has a masters degree from</rdfs:label>        <rdfs:domain rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#Person"/>        <rdfs:range rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#University"/>        <rdfs:subPropertyOf rdf:resource="http://swat.cse.lehigh.edu/onto/univ-bench.owl#degreeFrom"/>    </owl:ObjectProperty>
Thank you in advance for your clarifications.