Selection for egg shell strength in laying hens using shell membrane characteristics     

K. Johansson  J. Örberg  A.‐B. Carlgren  M. Wilhelmson 《British poultry science》1996,37(4):757-763

1. Divergent selection for attachment strength between the shell membrane and the calcium shell was performed in a White Leghorn strain. Multivariate analysis was used to estimate genetic parameters for shell membrane measurements and shell thickness. The aim was to investigate the possibility of improving shell strength in laying hens by selecting for increased attachment strength.

2. A significant direct selection response for attachment strength was achieved. There was a favourable correlated selection differential in the frequency of cracked eggs which resulted in a nonsignificant but favourable, correlated response. Selection for a strong attachment resulted in a thinner egg shell, and vice versa. Heritabilities were all relatively high (0.30 to 0.70). Most of the genetic correlations were in agreement with the achieved correlated responses.

3. Two factors that probably contributed to the responses in egg shell thickness were an unfavourable genetic correlation between attachment strength and shell thickness, and natural selection against changes in attachment strength, in the form of increased mortality during incubation and hatching. Problems connected with breeding for increased shell strength are discussed.  相似文献   

Helix pomatia a hemagglutinin, a surface marker for bovine T-lymphocytes     

Morein B  Hellström U  Axelsson L  Johansson C  Hammarström S 《Veterinary immunology and immunopathology》1979,1(1):27-36

Bovine peripheral blood lymphocytes (PBL) were isolated from blood collected from 6 cattle. After treatment with neuraminidase, 40 or 60% of the cells were shown to combine with Helix Pomatia A hemagglutinin (HP) depending whether a direct or indirect fluorescence technique was used. About 20% of the cells were Ig-bearing. With double staining fluorescence technique, it was shown that cells attaching to HP were not Ig-bearing and the reverse. With the aid of HP, covalently bound to Sepharose, Ig-bearing cells could be separated from cell populations attaching to HP. The fraction of cells forming rosettes with sheep erythrocytes was proportional to that of HP attaching cells both before and after fractionation on the HP column. It is therefore concluded that HP is a marker for bovine T-cells, and that this lectin may be used to separate B-cells from T-cells.  相似文献   

Ultrasonographic description of tendons and ligaments at the palmar (plantar) aspect of the distal limb in the one humped camel (Camelus dromedarius)     

SM Gadallah  AM Sharshar  SA Elsharkawy  MS Fadel 《Australian veterinary journal》2023,101(10):397-408

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Decreased susceptibility to doxycycline associated with a 16S rRNA gene mutation in Brachyspira hyodysenteriae     

Pringle M  Fellström C  Johansson KE 《Veterinary microbiology》2007,123(1-3):245-248

The objective of this study was to assess whether nucleotide substitutions in the 16S rDNA sequence of selected Brachyspira hyodysenteriae isolates could explain differences in doxycycline minimal inhibitory concentrations (MICs). The main part of the 16S rRNA gene was sequenced and compared for 19 isolates with different doxycycline MICs. A mutation in the 16S rRNA gene at the position corresponding to 1058 in Escherichia coli has been shown to cause tetracycline resistance in other bacteria. In the B. hyodysenteriae sequences a G1058C mutation was found for all isolates with increased doxycycline MICs whereas all susceptible isolates had the wild type sequence.  相似文献   

Retrospective survey of bronchoalveolar lavage fluid cytology in Western Australian horses presented for evaluation of the respiratory tract: effect of season on relative cell percentages          下载免费PDF全文

CJ Secombe  GD Lester  ID Robertson  AM Cullimore 《Australian veterinary journal》2015,93(5):152-156

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The Usefulness of Captive Kept Capercaillie (Tetrao urogallus L.) as the Semen Donors for Artificial Insemination and Gene Pool Preservation In vitro          下载免费PDF全文

ET Łukaszewicz  AM Kowalczyk 《Reproduction in domestic animals》2015,50(3):452-457

Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 10⁶ per ml to 3520 × 10⁶ per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons.  相似文献   

Effect of exogenous circulating anti-bPL antibodies on bovine placental lactogen measurements in foetal samples     

Andrea Vivian Alvarez-Oxiley  Noelita Melo de Sousa  Jean-Luc Hornick  Kamal Touati  Gysbert C van der Weijden  Marcel AM Taverne  Otto Szenci  Jean-Fran?ois Beckers 《Acta veterinaria Scandinavica》2010,52(1):9

Background

The involvement of placental lactogen (PL) in the regulation of foetal growth has been investigated in different species by in vivo immunomodulation techniques. However, when circulating antibodies are present together with the hormone, the procedure for hormonal measurement becomes considerably complex. The aim of this study was the immunoneutralization of bovine placental lactogen (bPL) concentrations in bovine foetal circulation by direct infusion of rabbit anti-bPL purified immunoglobulins (IgG) via a foetal catheter (in vivo study). The ability of a RIA based on guinea pig anti-bPL antiserum, for the measurement of bPL concentrations in samples containing exogenous rabbit anti-bPL immunoglobulins, was also analyzed in in vitro and in vivo conditions.

Methods

Six bovine foetuses were chronic cannulated on the aorta via the medial tarsal artery. Infusion of rabbit anti-bPL IgG was performed during late gestation. Pooled rabbit anti-bPL antisera had a maximal neutralization capacity of 25 μg bPL/mL of immunoglobulin. Interference of rabbit anti-bPL immunoglobulin with radioimmunoassay measurement using guinea pig anti-bPL as primary antibody was first evaluated in vitro. Polyclonal anti-bPL antibodies raised in rabbit were added in foetal sera to produce 100 samples with known antibodies titers (dilutions ranging from 1:2,500 till 1:1,280,000).

Result(s)

Assessment of the interference of rabbit anti-bPL antibody showed that bPL concentrations were significantly lower (P < 0.05) in samples added with dilutions of rabbit antiserum lower than 1:80,000 (one foetus) or 1:10,000 (four foetuses). It was also shown that the recovery of added bPL (12 ng/mL) was markedly reduced in those samples in which exogenous rabbit anti-bPL were added at dilutions lower than 1:20,000. Concentrations of foetal bPL were determined in samples from cannulated foetuses. In foetuses 1 and 6, bPL concentrations remained almost unchanged (<5 ng/mL) during the whole experimental period. In Foetus 3, bPL concentrations decreased immediately after IgG infusion and thereafter, they increased until parturition.

Conclusion(s)

The use of a bPL RIA using a guinea pig anti-bPL as primary antiserum allowed for the measurement of bPL concentrations in foetal plasma in presence of rabbit anti-bPL IgG into the foetal circulation. Long-term foetal catheterization allowed for the study of the influence of direct infusion of anti-bPL IgG on peripheral bPL concentrations in bovine foetuses.  相似文献   

Towards the understanding of bread-making quality in organically grown wheat: Dough mixing behaviour,protein polymerisation and structural properties     

A. Hussain  H. LarssonR. Kuktaite  M.L. Prieto-LindeE. Johansson 《Journal of Cereal Science》2012

Achieving high quality of organic bread is a major objective of organic wheat production. The aim of the present study was to understand the mechanisms related to bread-making quality in organically grown wheat genotypes from a diverse background. Fifty one organically grown winter and spring wheat genotypes were evaluated for percentage of unextractable polymeric proteins in total polymeric proteins (%UPP) in flour and dough, mixing behaviour and structural properties. The results showed a large variation in genotypes for %UPP in flour, changes in %UPP at mixing, mixing parameters and structural properties. Genotypes with high %UPP in flour and low change in %UPP at optimum mixing were; Agron, Hjelmqvist 6357 blå and Effrada. The light microscopy (LM) and confocal laser scanning microscopy (CLSM) results confirmed that genotypes with high %UPP in flour and a low change at optimal mixing resulted in a more extended protein network (continuous and interconnected) at mixing as compared to the other genotypes. Genotypes with good mixing properties as to the mixograph analyses were; Diamant ax, Lantvete Gotland 4496 spelt, Erbe brun and Jacoby 59. The present study shows the presence of opportunities to select genotypes suitable for cultivation and breeding of bread wheat for organic production.  相似文献   

Selection for sexual male characters and their effects on other fitness related traits in white leghorn chickens   总被引：1，自引：0，他引：1  

By M. Tufvesson  B. Tufvesson  T. von Schantz  K. Johansson  . and  M. Wilhelmson 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1999,116(2):127-138

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Peripheral and intracerebral T cell immune response in cats naturally infected with Borna disease virus.     

A L Berg  A Johannisson  M Johansson  A Hein  M Berg  R D?rries 《Veterinary immunology and immunopathology》1999,68(2-4):241-253

Borna disease virus (BDV) is a neurotropic agent with capacity to cause encephalomyelitis in a wide range of animal species, including horses and cats. Recent studies also point to a link between BDV and human neuropsychiatric disorders. The pathogenesis of Borna disease (BD) has been proposed to be immune-mediated, mainly through the effects of cytotoxic T cells. We used flow cytometric analysis in order to characterize the peripheral and intracerebral T cell immune response in cats naturally infected with BDV. Our results show the presence of two different CD8+ cell populations (CD8+low and CD8+high) in the blood, spleen and brain of these cats. In the brain, CD8+low cells predominated over CD8+high cells. Since CD8+low cells have been suggested to represent a non-MHC-restricted T cell population, the recruitment of such cells to the brains of BDV-infected cats could possibly be of importance for the clearance of virus from neurones.  相似文献