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Zimen, E. (1975). Social dynamics of the wolf pack. In M. W. Fox (Ed.), The wild canids (pp. 336–362). New York: Van Nostrand Reinhold.
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Zentall, T. R., & Hogan, D. E. (1975). Key pecking in pigeons produced by pairing keylight with inaccessible grain. J Exp Anal Behav, 23(2), 199–206.
Abstract: In Experiment I, keylight was paired with inaccessible grain delivery (under two conditions of keylight intensity) to determine if autoshaping would occur in the absence of primary reinforcement. In Experiment II, the procedure was repeated with accessible grain, for comparison. In Experiment III, the procedures were repeated with explicitly unpaired presentations of keylight and either inaccessible or accessible grain. The results indicated that key pecking occurred as quickly in the presence of keylight pairings with inaccessible grain as with accessible grain, though (except for one bird) key pecking was not maintained with inaccessible grain. Furthermore, compared to the dim keylight, the bright keylight greatly suppressed key pecking when paired with inaccessible grain, and reduced the rate of key pecking when paired with accessible grain. Little key pecking occurred in groups exposed to explicitly unpaired presentations of keylight (whether bright or dim) and grain (whether accessible or inaccessible). When the birds in Experiment III were retested with explicitly paired presentations of keylight and grain, little key pecking was observed, suggesting suppressive effects of prior explicitly unpaired presentations. It is suggested that the effects of key-brightness manipulation were produced by the association of grain with cues other than the response key, or by distraction produced by partial illumination of the grain hopper.
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Wood, F. E., & Cusanovich, M. A. (1975). The reaction of Euglena gracilis cytochrome c-552 with nonphysiological oxidants and reductants. Archives of Biochemistry and Biophysics, 168(2), 333–342.
Abstract: The reaction of Euglena gracilis cytochrome c-552 (cytochrome f) with the nonphysiological reactants potassium ferrocyanide, potassium ferricyanide, sodium ascorbate, sodium dithionite, and Chromatium vinosum high potential nonheme iron protein was studied by stopped-flow and temperature-jump kinetic methods. The reaction of the purified, water-soluble protein with the reactants was investigated as a function of ionic strength, pH, and temperature. The results demonstrated that reduction and oxidation takes place at a negatively charged site on the cytochrome c-552 surface. Participation of specific amino acid residues in electron transfer is implicated from the pH results. The results obtained for the nonphysiological reactions of cytochrome c-552 are compared with available data for horse heart cytochrome c and Rhodospirillum rubrum cytochrome c2. The results strongly suggest that Euglena gracilis cytochrome c-552 undergoes nonphysiological oxidation and reduction by a mechanism different from that found for cytochrome c or cytochrome c2.
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Western D,. (1975). Water availability and its influence on the structure and dynamics of a savannah large mammal community. E Afr Wildl J 1, 3, 265–288.
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Welsh Da,. (1975). Population, behavioural, and grazing ecology of the Sable Island, Nova Scotia. Ph.D. thesis, Dalhousie University, Halifax.
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Wang, L. Y. (1975). Host preference of mosquito vectors of Japanese encephalitis. Zhonghua Min Guo Wei Sheng Wu Xue Za Zhi, 8(4), 274–279.
Abstract: The host preference of 4 Culex mosquito species collected in Miaoli and Pingtung counties, Taiwan was studied by capillary precipitin method. Antisera to alum-precipitated sera of man, bovine, swine, rabbit, horse, dog, cat, mouse, chicken, duck, and pigeon were produced in rabbits and reacted with 758 mosquito blood meals among which reactions to one or more antisera. Culex annulus and Culex tritaeniorhynchus summorosus showed a great avidity for pig, and Culex fuscocephala for bovine. Culex pipiens fatigans was ornithophilic. None of 110 C. t. summorosus and 2.4% of 223 C. annulus had fed on man. Among 66 samples of C.p. fatigans tested 10.3% had fed on man, while none of 359 C. fuscocephala did. It seems that the latter does not act as a primary vector of Japanese encephalitis.
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Wagner, G. (1975). [Flight leadership in flocks of homing pigeons]. Z. Tierpsychol., (39), 61–74.
Abstract: Groups of 3-5 homing pigeons individually recognizable by different colours of their plumage were followed by helicopter on their way home. In most cases the animals flew together as a group with frequently changing leadership. Flight formations in terms of leadership were noted every minute. It was examined statistically whether the flight order varies at random or whether there are leading and led birds. In 6 out of 7 experiments with groups of 4-5 pigeons flight order was far from random, one or two pigeons proving to be leaders. In only one experiment leadership did not differ from a random distribution. No correlation could be found between the tendency to lead within a group and homing performance of the single pigeon when released individually.
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Syme, G. J., & Syme, L. A. (1975). The concept of spatial leadership in farm animals: An experiment with sheep. Anim. Behav., 23(Part 4), 921–925.
Abstract: The concept of spatial leadership as applied to farm animals is discussed with particular emphasis on methodological problems. Using three experimental procedures forced spatial leadership orders were measured in a group of Romney ewes. Comparisons between orders showed the effects of both the different experimental tasks and the social context on leadership structure. Both these variables were found to affect the orders obtained. The results are interpreted in terms of the utility of the concept of spatial leadership in domestic animals and the necessity for more systematic procedural investigations in this area.
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Sudia, W. D., Fernandez, L., Newhouse, V. F., Sanz, R., & Calisher, C. H. (1975). Arbovirus vector ecology studies in Mexico during the 1972 Venezuelan equine encephalitis outbreak. Am J Epidemiol, 101(1), 51–58.
Abstract: Virus vector studies were conducted in the States of Durango, Chihuahua, and Tamaulipas, Mexico, in June and July 1972. Apparently only a low level of Venzuelan equine encephalitis (VEE) virus transmission to equines occured at the time of the study, and the infection was restricted to areas which had not experienced overt activity during the preceding year. The low level of infection was associated with a scarcity of mosquitoes. The IB (epidemic) strain of VEE virus was isolated from two pools of Anopheles pseudopunctipennis (Theo.) and the blood of one symptomatic equine. The low mosquito population, the relatively few equine cases observed, and the absence of reports of VEE human disease from the outbreak area suggested VEE virus persistence through a low-level mosquito-equine transmission cycle. Other studies have already indicated that wild vertebrates play no more than a minor role in outbreaks of epidemic VEE. Mosquito collections made in areas of the states of Durango, Chihuahua, and Tamaulipas, where considerable epidemic activity of VEE had occurred in 1971, failed to reveal evidence of VEE virus persistence. Twenty-nine ioslations of other arboviruses were also made in these studies: including 22 of St. Louis encephalitis virus (SLE), 2 of Flanders virus, 1 of Turlock virus, 1 of Trivittatus virus of the California Group, 1 of western equine encephalitis virus (VEE), and 2 (from Santa Rose) which possibly represent a hitherto unknown virus in the Bunyamwera Group. These are the first reports of SLE virus isolations from mosquitoes in Mexico, and the first demonstration of Trivittatus, VEE Turlock and Flanders viruses in Mexico from any source.
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Stober, M., & Geiger, J. F. (1975). [Lamenting “moaning” in domestic cattle]. Dtsch Tierarztl Wochenschr, 82(1), 10–13.
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