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Niekerk Van Ch, A. W. (1975). Early embryonic development in the horse. J Reprod Fert Suppl, 23, 495–498.
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Nelson, W. A., Keirans, J. E., Bell, J. F., & Clifford, C. M. (1975). Host-ectoparasite relationships. J Med Entomol, 12(2), 143–166.
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Montagu I,. (1975). The wild ass of Africa. Wild Life, 17, 400–401.
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Mitchell, D., Kirschbaum, E. H., & Perry, R. L. (1975). Effects of neophobia and habituation on the poison-induced avoidance of exteroceptive stimuli in the rat. J Exp Psychol Anim Behav Process, 1(1), 47–55.
Abstract: Two experiments on the role of neophobia in poison-induced aversions to exteroceptive stimuli are reported. In Experiment 1, rats were given either 10 or 25 days of habituation to the test situation prior to conditioning. Those animals with the longer habituation period avoided a complex of novel exteroceptive stimuli while those with the shorter habituation period did not. In Experiment 2 rats initially avoided the more novel of two containers, but gradually came to eat equal amounts from both. A single pairing of toxicosis with consumption from either the novel or the familiar container reinstated the avoidance of the novel container in both cases. The results were discussed in terms of an interaction between habituation and conditioning procedures. It was suggested that previously reported differences between interoceptive and exteroceptive conditioning effects may have been influenced by the differential novelty of the two classes of stimuli in the test situation. It was further suggested that non-contingently poisoned control groups should routinely be included in poison avoidance conditioning studies.
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Mitchell, D., & Allen, W. R. (1975). Observations on reproductive performance in the yearling mare. J. Reprod. Fert.,, (Suppl. 23), 531–536.
Abstract: Reproductive performance was studied in 137 yearling mares run with stallions in small groups for 3 months between June and August in 1968 to 1971 (four breeding seasons). Pregnancy diagnosis by repeated rectal palpation and qualitative tests for PMSG, showed that ninety-five mares conceived of which forty-four aborted spontaneously between days 30 and 160 of gestation. Laboratory examination of twenty-one aborted fetuses failed to show any infectious agents. Serial quantitative and qualitative tests for PMSG in aborting animals gave results similar to those observed in mares with normal pregnancies. Plasma progestagen assays showed marked individual variations although the loss of the conceptus was always associated with a drop in progestagen level. The high incidence of early pregnancy loss in these pubertal mares may also be related to immaturity, inadequate nutrition and physical stress.
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Malcom Jr, L. H. (1975). Notes on wild dogs hunting zebras. Mammalia, 39, 231–240.
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Makarov, V. V., & Bakulov, I. A. (1975). [Zoopathogenic arboviruses, their systematics and ecology]. Veterinariia, (11), 39–41.
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Leuthold W, L. B. (1975). Temporal patterns of reproduction in ungulates of Tsavo East National Park Kenya. E Afr Wildl J, 13, 159–170.
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Klingel, H. (1975). Social organization and reproduction in equids. J Reprod Fertil Suppl, (23), 7–11.
Abstract: There are two distinct types of social organization and, accordingly, two types of mating systems in equids. In the horse, Plains zebra and Mountain zebra, the adults live in non-territorial and cohesive one-male groups and in stallion groups. The family stallions have exclusive mating rights which are respected by all others. In Grevy's zebra and in the African and Asiatic wild asses, the stallions are permanently territorial and have exclusive mating rights within their territories. Ecological and evolutionary aspects are discussed.
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Klingel H,. (1975). Die soziale Organisation der Equiden. Verh Dtsch Zool Ges in Karlsruhe, , 71–80.
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