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The ligand‐binding properties of hemoglobins from two homozygote phenotypes (AA and BB) of water buffalo (Bubalus bubalis) have been characterized by equilibrium and kinetic techniques. In the case of the BB phenotype, the two constituent hemoglobins have been purified and separately analysed. Buffalo hemoglobins display the reduced sensitivity to organic phosphates characteristic of ruminant hemoglobins, their physiological effector probably being the chloride ion. In contrast to the other known hemoglobins from ruminants, all the hemoglobins from the water buffalo display a significant temperature sensitivity, the ΔH for oxygen binding in the presence of physiological effectors approaching that of human hemoglobin (ΔH=−30.5 kJ/mol O2). This discrepancy with the other ruminant hemoglobins (e.g. ox, ΔH=−10.4 kJ/mol O2), whose primary structure is very similar to that of buffalo, hemoglobins might be correlated to the different habitat and phylogenetic history of the two subfamilies (Bos and Bubalus) of Bovidae.

The functional properties of hemolysates from the bats Rhinolophus ferrumequinum, Miniopterus schreibersi and Pipistrellus pipistrellus were studied at 25 degrees C and 37 degrees C over the pH range 7.0-7.4. The concentrations of 2,3-DPG and their effect on hemoglobin O2 affinity were also studied under the same conditions. At pH 7.4 and 37 degrees C hemoglobin O2 affinity was higher than in similarly-sized non-flying, normothermic mammals. The Bohr effect values in the three bat species were slightly lower than those reported for small non-flying mammals. The temperature sensitivities of the oxygenation reactions in bat hemoglobins were low, which may be a mechanism for avoiding the effects of abrupt body temperature changes on oxygen loading and unloading by hemoglobin. The levels of 2, 3-DPG high in red blood cells of active bats decrease when the bats are hibernating. Thus changes in hemoglobin O2 affinity are more probably due to changes in 2,3-DPG concentrations than to alterations of body temperature.

López-Luna P. 1990. Seasonal variations in hematological values and heart weight in two small mammals, a mouse Apodemus sylvaticus, and a vole: Pitymys duodecimcostatus. .Hematological values and relative heart weight were analyzed in two rodents: the mouse, Apodemus sylvaticus (Linnaeus, 1758), and the vole, Pitymys duodecimcostatus (de Sélys-Longchamps, 1839). The body weight of the two species was similar, 18.60 + 0.61 g for the mouse, versus 20.14 + 0.42 g for the vole. The specimens were captured in the same geographic area but in different ecological niches, since the vole is a burrowing animal, and the mouse is not. Hematological variations in both species were not related to age, sex, or gestation. P. duodecimcostatus had higher RBC count and Hb and He concentrations and lower MCV and MCH values than A. sylvaticus. However, MCHC values were almost the same in both species. The seasonal hematological variations observed in P. duodecimcostatus are like those found in most small mammals, while the hematological values found in A. sylvaticus barely changed throughout the year. The relative heart weight increased significantly in the two species during winter.