Equilibrium swelling behavior of uniaxially oriented nematic networks in nematogenic solvents has been studied in the temperature (T) range covering the two independent nematic-isotropic transition temperatures for the swollen network (T-NI(G)) and the surrounding solvent (T-NI(S); T-NI(G) > T-NI(S)). The swollen isotropic state smoothly changes into the shrunken nematic state with an elongation along the director axis within a narrow temperature range around TNIG. In the region of T-NI(S) < T < T-NI(G), where the surrounding solvents are in the isotropic state, the shrunken nematic gels reswell with a further increase in shape anisotropy upon cooling. In the totally nematic phase of T < T-NI(S), the shape anisotropy increases without significant volume change with decreasing T. A mean field theory satisfactorily describes the features of experimental data, although a sharp transition predicted disagrees with the smooth transition observed. The polydomain nematic network without global director orientation shows no anisotropy in swelling but exhibits substantially the same T dependence of swelling degree as the corresponding monodomain system. A striking difference is that the polydomain system undergoes a discontinuous volume transition, unlike the continuous transition in the monodomain system.