Use of space and activity budgets in relation to age and social status in a captive herd of American bison,Bison bison

A stable herd of 11 captive American bison (Bison bison) of known ages and social rank was studied between June 18 and August 6, 1979 at the Jardin zoologique du Québec, Charlesbourg, Quebec. During the 8-week study, the first author collected scan data of predefined behaviors and locations on all individuals of the herd. Space use analysis revealed extensive occupation of (and preference for) the barn and sand mound by higher-ranking animals and calves, and the tendency for lower-ranked individuals to use alternate, lower-quality sites. Overall, the herd spent an average of 40% of the daytime resting, 25% standing, 23% feeding, and 12% walking/running and group exploring. High-ranking individuals spent significantly more time standing and walking, and less time foraging than average. Most low-ranking individuals spent significantly less time lying, and more time feeding than average. Calves spent significantly more time lying than average. The extra feeding time of low-ranking individuals occurred mostly in early morning and mid-day, when the high-ranking individuals were mostly inactive. Our results suggest differential space and time use in relation to age and social status. The effects of resource limitations caused by captivity conditions, as compared with natural conditions, are discussed in regard to the activity and movement coordination of individuals in this particular captive herd. © 1993 Wiley-Liss, Inc.     

Identification of bovine and novel interferon-tau alleles in the American plains bison (Bison bison) by analysis of hybrid cattle x bison blastocysts

The objective of this study was to generate bison x cattle hybrid embryos by in vitro fertilization, to assess their developmental potential, to determine the pattern of secretion of the embryonic signaling molecule interferon-tau (IFN-tau), and to identify novel IFN-tau mRNA polymorphism in the American plains bison. A total of 600 bovine oocytes were inseminated with frozen-thawed bison semen. Of these, 40.7% cleaved and 14.8% proceeded to the blastocyst stage. Individual blastocysts were cultured on a basement membrane (Matrigel) and their ability to attach and form outgrowths was monitored. A total of 36 blastocysts were cultured of which 22 formed outgrowths. During individual culture, medium samples were collected and their IFN-tau concentration was measured. On day 6 after onset of individual culture, attached outgrowths produced significantly more IFN-tau than unattached viable or degenerate blastocysts. At this time, female conceptuses also produced significantly more IFN-tau than their male cohorts. However, by day 12 this difference had disappeared. Total mRNA was extracted from three individual outgrowths and analyzed by RT-PCR. Subsequent sequencing of 28 clones showed several known bovine IFN-tau sequences as well as two novel sequences termed bisIFN-tau1 and 2. To determine the origin of these, DNA was extracted from bison semen and analyzed by PCR. One bovine IFN-tau sequence (bovIFN-tau1d) as well as bisIFN-tau2 and a third novel sequence bisIFN-tau3 were detected. This study demonstrates the feasibility of using hybrid embryos for the analysis of developmentally regulated gene expression in species where embryos may not be available.     

Effectiveness of bovine microsatellites in resolving paternity cases in American bison, Bison bison L.

A set of 33 cattle microsatellite primer pairs was tested with the DNA of American bison from a captive population in Belgium and evaluated for usefulness in parentage testing. Two primer sets did not amplify and three were monomorphic. Among the polymorphic markers, the number of alleles ranged from two to nine. Heterozygosity, polymorphism information content (PIC) and probability of exclusion (PE) values were low by comparison with those obtained with the same markers in cattle. Two methods of estimating PE were used, one which assumed equal allele frequencies between parental sexes and another which took into account differences in allele frequencies between parental sexes. An internationally accepted set of nine microsatellites gives cumulative PE values of 0·98 and 0·97, respectively, for the two methods. The potential of this marker set to identify bison × cattle hybrids is discussed. Because bison and cattle have a common ancestor, these microsatellites are a useful way to establish genetic distances and can lead to the construction of phylogenetic trees.     

Host defense function in neutrophils from the American bison (Bison bison)

Selected host defense functions of neutrophils isolated from American bison (Bison bison) were characterized and compared with those of cattle (Bos taurus). Bison neutrophils had a robust chemotactic response to both IL-8 and LTB(4), with maximal responses occurring at 10(-7) M (IL-8) and 10(-8) M (LTB(4)). The magnitude of the chemotactic response to IL-8 was similar in bison and bovine neutrophils (except at 10(-7) M IL-8, where bison had a stronger response). In response to LTB(4), bison neutrophils had a much stronger chemotaxis at both 10(-8) and 10(-7) M than did bovine cells. Production of reactive oxygen species (ROS) in response to phorbol myristate acetate (PMA) and opsonized zymosan (OpZ) was similar between bison and bovine neutrophils. However, the production of ROS in bison neutrophils stimulated with OpZ was primarily intracellular, while extracellular release of ROS was evident in bovine neutrophils stimulated with OpZ. Like bovine neutrophils, bison neutrophils did not generate a respiratory burst in response to fMLF. Granules prepared from bison neutrophils had potent direct killing action on the Gram-negative bacteria Escherichia coli but failed to kill the Gram-positive bacteria Staphylococcus aureus and, at intermediate doses, actually had a permissive effect for this bacteria. Thus, bison neutrophils have potent host defense capabilities similar in quality to those of bovine neutrophils; however, unique differences are present, which may allow bison neutrophils to respond to the distinct immunological challenges that bison encounter.     

Isolation of a new foamy retrovirus from orangutans.

We have isolated a new foamy virus from blood samples taken from two apparently healthy orangutans (Pongo pygmaeus). The older orangutan has since died with encephalopathy after a brief acute illness, while the younger one, his grandson, remains well. These animals and 12 other orangutans had specific antibodies to foamy virus as measured by immunofluorescence. The new foamy virus and the antisera showed strong and specific neutralization, with only weak cross-reaction with other simian foamy virus strains. Southern blotting with gag and env probes of human foamy virus and PCR amplification showed that the new foamy virus, designated SFV-11, is related to, yet distinct from, previously characterized strains from humans, chimpanzees, and monkeys.     

Isolation of a retrovirus and a herpesvirus from a captive California sea lion

A non-oncogenic retrovirus was isolated from an explanted skin biopsy from a captive California sea lion (Zalophus californianus) with a history of recurring skin lesions. The morphology of the viral particles in electron photomicrographs was characteristic of a foamy virus, a retrovirus in the subfamily Spumavirinae. Viral cytopathic effects consistent with foamy virus infection were observed in subsequent explants of skin and lymph nodes and co-cultivated peripheral blood leukocytes. The sea lion with the persistent foamy virus infection later died from pericarditis caused by Pasteurella multocida. A herpesvirus was isolated from explants of lung.     

Characterization of Anaplasma marginale isolated from North American bison

Anaplasma marginale (Rickettsiales: Anaplasmataceae), a tick-borne pathogen of cattle, is endemic in tropical and subtropical regions of the world. Although serologic tests have identified American bison, Bison bison, as being infected with A. marginale, the present study was undertaken to confirm A. marginale infection and to characterize isolates obtained from naturally infected bison in the United States and Canada. Major surface protein (MSP1a and MSP4) sequences of bison isolates were characterized in comparison with New World cattle isolates. Blood from one U.S. bison was inoculated into a susceptible, splenectomized calf, which developed acute anaplasmosis, demonstrating infectivity of this A. marginale bison isolate for cattle. The results of this study showed that these A. marginale isolates obtained from bison were similar to ones from naturally infected cattle.     

Isolation of glutathione from bovine thymus and its significance to research relevant to immune systems

A peptide was isolated from bovine thymus when a cAMP assay guided fractionation; it was glutathione. Pure glutathione (isolated and purchased) at 1, 10, 20, 40 and 100 μg/ml was active, P<0.05–0.01, in the cAMP assay. Glutathione was not active in the mixed lymphocyte culture assay, but was active in assays using T-rosettes. Glutathione may now be separated to avoid its biological interference in assays guiding fractionation to a thymic hormone(s). It is credible that glutathione was in fractions studied biologically and clinically by others. Knowing that glutathione may function in the transport of amino acids across membranes, and that L-alanine is essential for human lymphocytes to respond to mitogenic and allogenic stimulation, it seems possible that glutathione might be functional in the complex immune systems.     

Glucocorticoids of bison bulls in relation to social status

A primary response to stress is an increase in circulating adrenal glucocorticoids (GC) such as cortisol. Two hypotheses propose differential stress responses to agonistic and aggressive interactions in social groups. If subordinate animals are subjected to social and psychological stressors leading to chronic GC elevation, the 'stress of subordination' hypothesis predicts that GCs will be higher in subordinates than dominants. Alternatively, if dominant animals are subject to physiological stressors (e.g., fight at higher rates than subordinates) or hierarchies are unstable, the 'stress of domination' hypothesis predicts higher GCs in dominant individuals. Both models predict that GC levels will peak during the breeding season. We tested these predictions in bison bulls (Bison bison) using fecal steroid analysis to characterize GC concentration and behavioral observations to determine dominance rank, copulatory success, and tending status of bulls. Fecal samples were collected during 2003 from adult bison bulls during pre-rut (June), rut (July-August), and post-rut (September). Matched sample data indicated that mean GC levels (ng/g feces) of bulls strongly peaked during the 4-week rut, doubling from pre-rut to rut and then declining again during post-rut. High ranked dominant bulls maintained higher GC levels than lower ranked subordinate bulls. Dominance rank was positively correlated with copulatory success and age, and dominant bulls were more likely to tend (guard) cows as they approached estrus. There was a positive correlation between GC level and copulatory success, with prime-aged bulls (> or =7 years) obtaining the most copulations. GC levels were positively correlated with bull androgen levels determined in a previous study. These results support the 'stress of domination' hypothesis, indicating that dominant bison bulls pay a significant physiological price for high social status and the opportunity to mate.     

牛sox2基因的克隆及重组反转录病毒载体的构建

为了构建包含牛sox2基因编码序列的重组反转录病毒载体,获得有感染性的病毒颗粒,本研究以胎牛原始生殖嵴为材料,用RT-PCR方法克隆出牛sox2基因的开放阅读框序列,将其亚克隆至pMD18-T载体并测序。结果表明获得的基因片段与发表的牛sox2基因序列(Gen Bank Accession No.NM-001105463)高度同源;将测序正确的重组T载体用EcoRI和BglII酶切,基因片段插入反转录病毒载体pMSCVneo的相同酶切位点,成功构建了重组反转录病毒载体pMSCV-sox2。采用脂质体法用pMSCV-sox2转染包装细胞PT67,同时用pMIG(含绿色荧光蛋白)作为阳性对照,经流式细胞仪测定,该载体转染效率达到68.3%;转染后PT67细胞经G418筛选得到稳定的产毒细胞株,其病毒滴度达8.16×107CFU/mL,为下一步特定因子诱导牛体细胞转变为牛iPS细胞的研究奠定了基础。     

Activator-dependent and activator-independent defective recombinant retroviruses from bovine leukemia virus.

The replication-competent bovine leukemia virus (BLV) has been modified for use as a vector for foreign genes. The gag, pol, env, and pX regions of the virus were replaced by an exogenous nuclear location signal LacZ (nlsLacZ) or SVnlsLacZ gene. Transfection of the ovine cell line FLK-BLV, which expresses all BLV proteins from a wild-type provirus, with this viral DNA resulted in a viral titer of 10(4) CFU/ml. The inclusion of a large portion of the gag region did not significantly increase the titer. Both activator-dependent and activator-independent retroviruses were constructed. In activator-dependent vectors, the expression of the insert was dependent on the presence of the Tax protein, which activated the BLV long terminal repeat. In activator-independent vectors, the expression of the insert was constitutive because of the presence of an internal promoter. Infections with the recombinant retrovirus were inhibited by specific neutralizing antibodies. The structure of the transduced genetic material was not rearranged. BLV vectors encoding a reporter nlsLacZ gene, the product of which can be detected in single cells, greatly simplified studies of their biological properties. Determination of the host range of BLV vectors established that BLV-based recombinant retroviruses are effective in the transduction of genes in a variety of species and cell types.     

Isolation of lipofuscin from the bovine myocardium

The paper describes the procedure of lipofuscin isolation from bovine myocardium with the use of 15-45% (weight/volume) linear gradient of sucrose density and differential centrifugation. Two coloured populations of lipofuscin granules with different density have been distinguished. Electron microscopic studies of the isolated lipofuscin have revealed the homogeneity of fractions and good maintenance of the granules. The electron microscopic, absorptive and luminescent spectral properties of lipofuscin preparations correspond to its properties in situ. The isolation of lipofuscin preparations suggests the possibility of studying the chemical composition and intramolecular structure of the granules.