scholarly journals A third component causing random variability beside environment and genotype. A reason for the limited success of a 30 year long effort to standardize laboratory animals?1,2

2012 ◽  
Vol 41 (2) ◽  
pp. 335-341 ◽  
Author(s):  
Klaus Gärtner
1990 ◽  
Vol 24 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Klaus Gärtner

This paper is a review of experiments, performed in our laboratory during the past 20 years, designed to analyse the significance of different components of random variability in quantitative traits in laboratory rats and mice. Reduction of genetic variability by using inbred strains and reduction of environmental variability by highly standardized husbandry in laboratory animals did not remarkably reduce the range of random variability in quantitative biological traits. Neither did a tremendous increase of the environmental variability (i.e., living in a natural setting) increase it. Therefore, the postnatal environment cannot be that important as the source of random variability. Utilizing methods established in twin research, only 20–30% of the range of the body weight in inbred mice were directly estimated to be of environmental origin. The remaining 70–80% were due to a third component creating biological random variability, in addition to the genetic and environmental influences. This third component is effective at or before fertilization and may originate from ooplasmic differences. It is the most important component of the phenotypic random variability, fixing its range and dominating the genetic and the environmental component. The Gaussian distribution of the body weights observed, even in inbred animals, seems to be an arrangement supporting natural selection rather than the consequence of heterogeneous environmental influences. In a group of inbred rats, the males with the highest chance of parenting the next generation were gathered in the central classes of the distribution of the body weight.


Author(s):  
Salman Khan ◽  
Molly Madan

Objective:- Hepatitis B is noteworthy medical issues that may include the late continuation of liver cirrhosis and hepatocellular carcinoma. The present study aimed for the detection and diffrentiation of Hepatitis B virus HBsAg inactive non-replicative carriers, HBeAg-positive inactive replicative carriers, active carriers & HBeAg-negative chronic hepatitis B by Real Time PCR and their genotyping Methods: This research conducted on 245 positive for HBsAg, 118 (48.16 %) were male and 127 (51.84%) were female patients, which was performed in central research station labortory of Microbiology at netaji subhash Chandra Bose subharti Medical College and Hospital, Meerut Between march 2016 to November 2017 The sera were separated and screened for HBsAg by ELISA kit. Positive samples for HBsAg were tested for HBeAg ELISA kit and DNA Viral load then sequenced for genotying Results:. Of the 245 HBsAg Positive case 55 (1.12%) were HBeAg positive. In 16 PCR positive and HBV genotyping, In HBsAg inactive Non-Replicative 37.5% (n=6) genotype-B and 6.25% (n=1) genotype-A, In HBeAg inactive Replicative 12.5% (n=2) genotype-B and 12.5% (n=2) genotype-A and In HBeAg Active Chronic Hepatitis B 18.75% (n=3) genotype-B and 12.5% (n=2) genotype-A were detected Conclusions: Management strategy, using HBsAg, HBeAg and HBV DNA viral load, seems adequate for the confirmation and diffrentiation of Hepatitis B virus inactive, active carriers & HBeAg-negative chronic hepatitis B patients and genotype B was more prevalent in comparission to genotype A. Distribution of carriers & genotypes, help physicians to prescribe proper antiviral/interferon therapy according to current genotyping pattern in this region Keywords: Hepatitis B virus, Carrier State, HBsAg, HBeAg, RT-PCR


2019 ◽  
Vol 331 (8) ◽  
pp. 25-27
Author(s):  
N.Y. Morozov ◽  
◽  
S.I. Tchukina ◽  
E.I. Koveshnikova ◽  
◽  
...  

Author(s):  
Rafael Antonio Caldart Bedin ◽  
Maisa Schultz ◽  
Antonio Bedin

Anesthesia for laboratory animals is a matter of biomedical concern and one of the most present dilemmas in the current bioethical debate. The use of anesthetic agents in experimental surgery aims at analgesia and restraining the animal, in order to achieve a reasonable degree of muscle relaxation and to produce sufficient analgesia. This practice requires the use of protocols for the administration of safe and efficient doses. Eight New Zealand rabbits were submitted to laparotomies demonstrating the surgical technique discipline of the local medical course. For pre-anesthetic medication, acepromazine 1 mg.kg-1 associated with ketamine 15 mg.kg-1 was used subcutaneously. Anesthesia was maintained with isoflurane and oxygen under a laryngeal mask in a Mapleson D anesthesia system and under spontaneous breathing. Hydration was performed with 10 ml.kg-1 saline every hour. A thermal mattress was used. Precordial stethoscope, pulse oximetry and clinical parameters were used for monitoring. For euthanasia, ketamine 10 mg.kg-1 associated with potassium chloride 19.1% 1 ml.kg-1 was used intravenously. The average weight of the rabbits was 2721.25 ± 275.01 grams and the duration of the anesthetic procedure was 120 ± 87 minutes. Discussion. In long-term anesthesia, such as laparotomies, the use of pre-anesthetic medication and then anesthetic induction by the combination of agents is recommended. However, anesthetic management requires monitoring to prevent insufficient or excessive doses from occurring.


2014 ◽  
Vol 17 (3) ◽  
pp. 421-426 ◽  
Author(s):  
B. Tokarz-Deptuła ◽  
P. Niedźwiedzka-Rystwej ◽  
B. Hukowska-Szematowicz ◽  
M. Adamiak ◽  
A. Trzeciak-Ryczek ◽  
...  

Abstract In Poland, rabbit is a highly valued animal, due to dietetic and flavour values of its meat, but above all, rabbits tend to be commonly used laboratory animals. The aim of the study was developing standards for counts of B-cells with CD19+ receptor, T-cells with CD5+ receptor, and their subpopulations, namely T-cells with CD4+, CD8+ and CD25+ receptor in the peripheral blood of mixed-breed Polish rabbits with addition of blood of meet breeds, including the assessment of the impact of four seasons of the year and animal sex on the values of the immunological parameters determined. The results showed that the counts of B- and T-cells and their subpopulations in peripheral blood remain within the following ranges: for CD19+ B-cells: 1.05 - 3.05%, for CD5+ T-cells: 34.00 - 43.07%, CD4+ T-cells: 23.52 - 33.23%, CD8+ T-cells: 12.55 - 17.30%, whereas for CD25+ T-cells: 0.72 - 2.81%. As it comes to the season of the year, it was observed that it principally affects the values of CD25+ T-cells, while in the case of rabbit sex, more changes were found in females.


ORL ro ◽  
2016 ◽  
Vol 1 (1) ◽  
pp. 24-26
Author(s):  
Ruxandra Bartok ◽  
Bogdan Dimitriu Dimitriu ◽  
Constantin Vârlan ◽  
Radu Stanciu ◽  
Georgiana Moldoveanu ◽  
...  

Rapid maxillary expansion is defined as the release of medio-palatine suture using an orthopedic forces. The role of this procedure is to expand  the upper jaw in order to achieve the  broadening of the upper arch. This study was initiated to quantify the effects of disjunction and post- treatment bone changes, after an adequate contention which lasted for three weeks. This study  is  carried on laboratory animals (common breed rabbit) to determine tensile strength and the elasticity modulus of  biological materials  used in orthdodontics. The results of the study are consistent with those reported in the literature reference.  


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