184,636 research outputs found
Don Finch
No full text"47757 RAAF Don Finch 2 Sqdn 1942-3".47757 Don Finch. Royal Australian Air Force. 2 Squadron 1942-1943
Activity-dependent plasticity in visual forebrain areas of the zebra finch
No full textRollenhagen A, Bischof H-J. Activity-dependent plasticity in visual forebrain areas of the zebra finch. Behavioural Brain Research. 1996;81(1-2):207-213
Correspondence from Fred J. Finch to Arlington State College President Jack R. Woolf
No full textCorrespondence from Fred J. Finch, attorney at Bunkley & Finch Law Offices in Dallas, to Arlington State College President JackR. Woolf, dated May 25, 1962. In the letter, Finch informs Woolf that he has been retained by three Black students (Ernest Hooper, Jerry Hanes, and Leaston Chase) to aid in their admissions request to Arlington State College.https://mavmatrix.uta.edu/specialcollections_jackrwoolfpapers/1020/thumbnail.jp
Phase specific morphological changes induced by social experience in two forebrain areas of the zebra finch
No full textRollenhagen A, Bischof H-J. Phase specific morphological changes induced by social experience in two forebrain areas of the zebra finch. Behavioural Brain Research. 1994;65(1):83-88.We examined the changes of spine density in Golgi preparations of two different areas of the forebrain of the zebra finch, the ANC (Archi-Neostriatum caudale) and MNH (medial Neo-Hyperstriatum) during development, after transferring male birds from isolation to a social condition (exposure to a female for 1 week), and after a second isolation period. MNH and ANC are two of four brain regions which are strongly activated if a male bird is exposed to a female after some time of isolation. The results of our study can be summarized as follows. 1: a peak-decline trend is observed in ANC, but not in MNH. 2: rearing conditions do not affect the development of both areas until day 70. 3: from 80 days of age, isolation leads to reduced spine density within ANC, but to enhanced spine density within MNH. 4: short social contact after isolation diminishes or eliminates the effects of isolation by an enhancement of spine density in ANC and a reduction of spine density within MNH. 5: the effects of short social rearing after isolation are reversible within ANC, but not within MNH. We presume that the alterations of spine density, which are induced by changes in social conditions, are restricted to ages older than 70 days by hormonal factors. We propose that the complexity of the ANC neuronal net follows the complexity of the social environment, and that the level of arousal is the most important factor influencing the complexity. We further suppose that the reduction of spines within MNH is the anatomical manifestation of an imprinting process, which has been shown to occur in the same experimental situation as we used it in our study
Posthatching development of synapses in the neuropil of nucleus rotundus of the zebra finch: a quantitative electron microscopic study
No full textNixdorf B, Bischof H-J. Posthatching development of synapses in the neuropil of nucleus rotundus of the zebra finch: a quantitative electron microscopic study. The Journal of Comparative Neurology. 1986;250(1):133-139.The development and maturation of synapses in the nucleus rotundus of the zebra finch were examined at 1, 5, 10, 20, and 100 days posthatching. Quantitative ultrastructural techniques were applied to investigate synaptic density, size of presynaptic terminals, and length of postsynaptic thickenings. During development there is a steady increase in the number of synapses and an enlargement of the presynaptic terminals. The length of the postsynaptic thickenings, however, decreases significantly during posthatching development. All three parameters reach adult values within 20 days of age. A close relationship was found between the enlargement of the presynaptic terminals and the increase in the number of contact zones up Lv the 20th day. The general feature of this developmental progress is in good agreement with biochemical and, to a certain extent, behavioral studies
Gene duplication and fragmentation in the zebra finch major histocompatibility complex
No full textBACKGROUND:
Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC) has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC) sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines.
RESULTS:
The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH) evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes.
CONCLUSION:
The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving chromosomal fission, gene duplication and translocation in the history of the MHC in birds, and highlight striking differences in MHC structure and organization among avian lineages
Delayed development of song control nuclei in the zebra finch is related to behavioral development
No full textHerrmann K, Bischof H-J. Delayed development of song control nuclei in the zebra finch is related to behavioral development. The Journal of Comparative Neurology. 1986;245(2):167-175.The postnatal development of two visual areas (nucleus rotundus and ectostriatum) and two song control areas (hyperstriatum ventrale pars caudale, HVc, and nucleus robustus archistriatalis, RA) of the zebra finch brain was followed from birth to adulthood. The following parameters were investigated: (1) neuron size, (2) volume of the brain nuclei, and (3) myelination of axons. The nucleus rotundus, the diencephalic station of the tectofugal pathway, exhibits the fastest development: rotundal neurons reach their maximum size at 20 days of age; the volume of this structure reaches adult size at the same time. The process of myelination begins between day 5 and day 10 and is completed at 40 days of age. A similar temporal sequence of development is seen in the ectostriatum, except myelination starts some days later. Thus the development of these visual areas is completed at 40 days. In, contrast, the development of the song control nuclei is delayed. Neurons in RA and HVc grow steadily up to 40 days of age, attaining a size larger than that observed in adults. Whereas the volume of HVc increases until day 40 and remains stable thereafter, RA volume increases until day 70 and evidences a decrease thereafter. It is not until postnatal day 20 (RA) and day 40 (HVc) that the myelination process starts in the song control areas. Adult myelin density is achieved by 70 days in RA and by 100 days in HVc. It can be demonstrated that the development of the visual system parallels the development of visual performance of the birds. Delayed growth of song control nuclei coincides with development of song
Zebra finch mid-piece analysis R script
No full textR script of the analysis reported in the manuscript 'A trade-off between thickness and length in the zebra finch sperm mid-piece'
Stabilization of sexual preferences by sexual experience in male zebra finches, taeniopygia guttata castanotis
No full textBischof H-J, Clayton N. Stabilization of sexual preferences by sexual experience in male zebra finches, taeniopygia guttata castanotis. Behaviour. 1991;118(1):144-154.Male zebra finches, Taeniopygia guttala castanotis, were normally-raised by zebra finches or were cross-fostered to Bengalese finch, Lonchura striata, foster-parents until 40 days of age. Following isolation until day 100, half the birds in each group were housed with a zebra finch female for seven days, isolated for three days and then housed with a Bengalese finch female for seven days. The other birds were exposed to females in the reverse order. Subsequent double-choice tests showed that all the normally-raised birds preferred zebra finch females whereas the preference of cross-fostered males depended on the order of exposure to the two females: those exposed first to a Bengalese finch female preferred Bengalese finch females whereas of those exposed first to a zebra finch female, some preferred zebra finches, some preferred Bengalese finches and some showed no marked preference for either female. In order to examine the question of why the latter group showed such markd individual variation in their sexual preferences, a further group of males were cross-fostered to Bengalese finches and exposed to a zebra finch female and then to a Bengalese finch female and their behaviors were observed from day 21 until day 40 and for the two, seven-day periods with the females. The results showed that, when comparing brothers within clutches, the one that begs and is fed more by its foster-parents develops a stronger preference for Benglese finch females and that the more song phrases a male directs to the zebra finch female during the first seven-day period, the stronger the sexual preference for zebra finch females in the double-choice tests. Hence, our results confirm and extend those of IMMELMANN et al. (1991) and KRUIJT and MEEUWISSEN (1991) that sexual imprinting may be a two step process. As a first step, information about the parents is learned during a sensitive period early in life. In a second step, this information has to be tested for its validity for the selection of a sexual partner during first courtship encounters. It is the second step where the previously stored information is stabilized in memory. Giving conflicting information during the first and the second step, one can show that interactions between the young male and its parents as well as with the first sexual partner influence the final preference it shows in subsequent double choice tests
Isolation-dependent enhancement of 14C-2-deoxyglucose uptake in the forebrain of zebra finch males
No full textBischof H-J, Herrmann K. Isolation-dependent enhancement of 14C-2-deoxyglucose uptake in the forebrain of zebra finch males. Behavioral and Neural Biology. 1988;49(3):386-397.In a previous study (H. J. Bischof and K. Herrmann (1986), Behavioral Brain Research, 21, 215-221) we demonstrated that four forebrain areas of the zebra finch male are activated in situations which arouse the animal, for example when the birds are chased around the cage or when they are exposed to a female. These areas, the hyperstriatum accessorium-dorsale (HAD), a part of the medial neo-hyperstriatum (MNH), the lateral neo-hyperstriatum (LNH), and a portion of the caudal archi-neostriatum (ANC), show enhanced 2-[14C]deoxyglucose (2-DG) uptake according to the experimental situation. On the basis of these experiments, we examined whether the activation of the areas is correlated with motor activity and is influenced by different isolation times prior to a 2-DG experiment, where courtship of the male birds is elicited by exposing them to a female zebra finch. For this purpose, we isolated male zebra finches for 1 day, 1 week, or 8 weeks, respectively, before we injected the 2-DG and exposed the birds to a female. During the experiment, besides other activities, the number of song motifs performed by the bird and the frequency of changing perches was recorded. Our experiments demonstrate that there is a weak negative correlation between motor activity and 2-DG uptake, and a positive correlation between isolation time and 2-DG uptake. We suggest that long isolation blocks courtship behavior by some unknown mechanisms, and that the "internal drive" of the animal, which possibly corresponds with the activity of the four forebrain areas, is enhanced by isolation and by the fact that the birds do not perform the consummatory behavior. Our results also demonstrate that the 2-DG method can show up small differences in the internal state of an animal, which cannot easily be detected by behavioral measurements
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