Effect of enrichment on stress level of laboratory rats

In certain biomedical research protocols, there is a need to singly house experimental rats. Since rodents are classified as social animals in nature, housing rats singly will result in stress to the animals. The aim of this study was to determine the effect of enrichment to the stress leukogram, feed intake, weight gain and behavior of singly-housed rats as opposed to singly-housed rats without enrichment and pair-housed rats. Eighteen 5 weeks old, male Sprague-Dawley rats were randomly assigned to three groups; singly-housed without enrichment, singly-housed with enrichment (provided with enrichment nestlets), and pair-housed. The rats were acclimatized for 7 days before start of study. Blood samplings were done on days 0, 14 and 26 for complete blood and differential counts. Feed intake and weight gain were recorded every 4 days and on days 0, 14 and 26. Behavioral assessment was done every week for 10 minutes for each cage. Results showed significant neutropenia in the singly-housed rats with and without enrichment as opposed to neutrophilia in the pair-housed rats. Monocytosis and eosinophilia were also more evident in the singly-housed rats without enrichment than in either the pair-housed rats or singly-housed rats with enrichment. However, there was no significant difference in other blood parameters, feed intake and weight gain. Singly-housed rats without enrichment also showed significantly higher stereotypical behavior when compared to rats in the other two groups. Thus, it could be concluded that singly-housed rats did not show higher stress level than pair-housed rats in the short term. Enrichment nestlets too have been proven to be effective in reducing some degree stress, aggression and stereotypical behavior in singly-housed rats

Effect of stocking density on Haematological indices and welfare of grower rabbits (Oryctolagus cuniculus) in tropical climate.

Ten New Zealand white cross rabbits of mixed sexes aged 10 weeks were used to evaluate the effect of stocking density (1 m2/rabbit and 0.1 m2/rabbit for 29 days) on haematological indices and welfare parameters in tropical climate. The rabbits were divided equally and allotted to the two stocking densities corresponding to an area of 0.5 m2 for Group A and 5 m2 for Group B. The rabbits were fed ad libitum with commercial rabbit grower pellets and fresh water was freely available throughout the study period. Each treatment group was also given carrot every Saturday and alfalfa hay every Monday evening as dietary enrichment. Group B rabbits had higher packed cell volume, haemoglobin concentration, mean corpuscular volume and mean corpuscular haemoglobin concentration and recorded a steeper rise of these indices over time when compared to Group A rabbits. Neutrophil/Lymphocyte ratio showed a correlation between social hierarchy and the availability of more space. Group A rabbits had higher weight gain and feed efficiency compared to that of Group B rabbits. However Group B rabbits recorded higher locomotor activity and Group A rabbits were observed to be utilizing the raised platform more. Both groups enjoyed the dietary enrichment exhibiting increased locomotor activity. The results of the study indicate that rabbits kept at 1 m2/rabbit had better haematological indices and locomotion activities compared to rabbits kept at 0.1 m2/rabbit in the tropical climate of Malaysia

Seroprevalence of helicobacter hepaticus in mice from laboratary animal facilities in Klang Valley, Malaysia

Helicobacter is a genus of Gram-negativebacteria possessing a characteristic helix shape. They were initially considered to be members of the Campylobacter genus, but since 1989 they have been grouped in their own genus. Helicobacter hepaticusis an enterohepatic Helicobacter species (EHS) belonging to the family Helicobacteriaceae of the order Campylobacterales of Epsilon-proteobacteria division. It is a Gram-negative, microaerophilic, urease-positive, spiral rod. H. hepaticus colonises the colon and invades the liver of mice causing chronic severe active hepatitis and proliferative typhlocolitis. It can also induce hepatocellular carcinomas in certain breeds. The bacterium has been associated with inflammatory bowel disease in immunocompromised mice. Certain strains of mice will develop a proliferative, inflammatory typhlitis and/or colitis that may result in rectal prolapse. Detection of H. hepaticus in laboratory mice is therefore important because of its effect on research animals ultimately complicating the research findings. Currently PCR, culture, serology test or histologic examination of silver-stained liver sections is used to diagnose H. hepaticus infection. Most mice colonised with helicobacters remain asymptomatic for long periods of time. This study was conducted to investigate the serological prevalence of Helicobacter hepaticus in mice in 5 laboratory facilities in the Klang Valley. Fifty sera were collected and examined for presence of H. hepaticus antibodies by commercial ELISA test kit. Result showed two facilities had positive sera towards H. hepaticus while the rest were negative. Four of fifty sera were positive while other serum samples were negative

Improvement of Mechanical Welding Properties by using Induced Harmonic Vibration.

The enhancement of the welding mechanical properties and the quality of the fusion metal is considered recently by using vibration during welding. In this study, the effect of induced harmonic vibration during welding is employed to improve the welding mechanical properties and to reach the best shape of welding line on the surface. The harmonic vibration method is examined experimentally by using four values of mechanical frequency during welding on the ductility, tensile strength and the homogeneity of the welding line. The frequencies were specified according to the natural frequency of the plate. Five simply supported rectangular plates are supported on the supporting stand and welded using a manual arc-welding machine. The experimental results show that the vibration applied during welding generally improved the bend property of the welding line, as well as the tensile strength has been improved distinctively at the resonance case when compared with that one welded without vibration. The morphology of the fillet metal after welding and for each value of frequency show an enhancement in the distribution of the fusion fillet metal, with gradually disappearing of the micro crack that may shown inside the metal with increasing the mechanical frequency. A comparison between the properties of welding without vibration and welding with vibration is discussed

Investigating Iraqi EFL College Students' Attitude towards Using Cooperative Learning Approach in Developing Reading Comprehension Skill

This study aims at investigating Iraqi EFL college learners’ attitudes toward using cooperative Learning approach on developing reading comprehension skill. The study is restricted to third– year college students of the English language in Misan Governorate during the second term of the academic year 2015–2016. The number of the whole population is (200) which is distributed into two types: pilot and main. The sample of the study consists of 40 students. To achieve the aim of the study, students' questionnaire consisting of (46) items is applied as an instrument. In order to get required data, a t-test analysis shows a statistically significant difference about learners’ attitudes toward using cooperative learning approach on developing reading comprehension skill. The obtained results are that: which refer to (Cooperative learning helps everyone reach the goal equally) from cooperative learning and (Reading in English is difficult for me) form Reading comprehension. Gain the low effectiveness. They got a weighted mean 56% and 40%. Items number (11, 29, 37, 43) which refer to (Cooperative learning requires much more time to study) & (I think reading the texts is easier if I study within a group) from cooperative learning and (I forward to coming to my reading class.)& (I m a afraid of making mistakes in my reading class) form Reading comprehension. All got (96%)

Modification of Malaysian dolomite using mechanochemical treatment via different media for oil palm fronds gasification

Exploitation of biomass wastes gives new hopes in the exploration of clean alternative fuel source such as hydrogen energy. The application of catalysts plays a major role in the process by enhancing the production of hydrogen via reformation and tar cracking reaction. However, certain drawbacks such as catalyst cost, deactivation, and regeneration remain unsolved in this process. In this study, we focused on potential Malaysian dolomite (Perlis) as the source of catalysts for palm frond gasification. The influences of mechanochemical treatment in three different media (air, ethanol, and water) on the catalytic activity of the material were analyzed. Important changes in the properties of the dolomite along with the high catalytic performance were noted as the results of the treatment. Notable changes in the dolomite structure and porosity were observed because of the impact of the treatment. Increment in the surface area of the catalysts boosts the H2 production and catalytic activity of dolomite. Moreover, substantial CO2 reduction was also observed during reaction as a result of the absorption capacity of treated dolomite. Thus, through mechanochemical treatment, the property of Malaysian dolomite is being greatly altered, which really suits as a potential catalyst for gasification

Expression of P-selectin, TXA2, TGF-β1 and PDGF-AB in the Presence of Bioadhesive Chitosan Derivatives

Chitosan is a natural macromolecular polysaccharide, derived from chitin extracted from the exoskeleton of some marine invertebrates. This study was designed to evaluate the expression of P-selectin, thromboxane A2 (TXA2), transforming growth factor-β1 (TGF- β1) and platelet derived growth factor-AB (PDGF-AB) using enzyme-linked immunosorbent assays (ELISAs). The chitosan derivatives utilized were 7% N,Ocarboxymethylchitosan (NO-CMC) (with 0.45 mL collagen), 8% NO-CMC, oligo - chitosan (O-C) and oligo -chitosan 53 (O-C 53). We found that O-C showed a significantly superior effect compared to NO-CMC in achieving hemostasis. Post-hoc multiple comparisons using Scheffe test indicated that p-values between the mean differences of all the assayed chitosan derivatives were not significant. However, our analyses successfully identified distinctions between the O-C and NO-CMC test groups and blood alone. These results may expand the understanding of the ability of chitosan derivatives to promote inflammatory responses and angiogenesis depending on their physical and chemical structure

Effect of local versus imported rodent diet on body weight and blood parameters of Sprague-Dawley rats.

This study was conducted to determine the effect of short-term (28 day) feeding of a local and two imported rodent diet on the body weight and blood profile of the Sprague-Dawley rats. Thirty female Sprague-Dawley rats aged between five to six weeks were placed in pairs in the polyethylene cages. Water and feed were given ad libitum. The rats were assigned to three groups where one group was fed the local diet; the second fed a United States of America diet and the third an Australian diet. The rats were weighed on days 0, 7, 14, 21 and 28 and the feed excess weighed every two days. From this study, it can be concluded that in short-term feeding, the body weight of Sprague-Dawley rat were affected by the type of diet. However, there was no significant difference between blood parameters of rats fed local and imported diet. This also holds true for the liver enzymes. However, there was a significant (p>0.05) difference in blood urea nitrogen (BUN) concentrations between these rats. The Australian diet produced less effect on BUN concentrations

Current Research Trends In Wire Electrical Discharge Machining (WEDM): A Review

Wire Electrical Discharge Machine (WEDM) is a ‘non-traditional machining process’ and becoming more important in providing a non-contact machining process which is suitable for machining geometrically complex and hard advanced material which impossible to machine by conventional machine. This paper reviews the experimental investigation results on performance evaluation of machining parameters which effect machining performance which will reflect the machining factors and responses. In addition, the method in analyzing, modelling, development and tool steel in WEDM were also discussed. Last but not least, some recommendations and future WEDM research were propos

Successful transfer of plasmid DNA into in vitro cells transfected with an inorganic plasmidMg/Al-LDH nanobiocomposite material as a vector for gene expression

The delivery of a full plasmid, encoding the green fluorescent protein gene into African monkey kidney (Vero3) cells, was successfully achieved using nanobiocomposites based on layered double hydroxides. This demonstrated the potential of using the system as an alternative DNA delivery vector. Intercalation of the circular plasmid DNA, pEGFP-N2, into Mg/Al-NO−3 layered double hydroxides (LDH) was accomplished through anion exchange routes to form the nanobiocomposite material. The host was previously synthesized at the Mg2+ to Al3+ molar ratio Ri = 2 and subsequently intercalated with plasmid DNA. Size expansion of the interlamellae host from 8.8 ° A in LDH to 42 °A was observed in the resulting nanobiocomposite,indicating stable hybridization of the plasmid DNA. The powder x-ray diffraction (PXRD)results, supplemented with Fourier-transform infrared (FTIR) spectroscopy, compositional and electrophoresis studies confirmed the encapsulation episode of the biomaterial. In order to elucidate the use of this resulting nanobiocomposite as a delivery vector, an MTT assay was performed to determine any cytotoxic effects of the host towards cells. The intercalated pEGFP-N2 anion was later successfully recovered through acidification with HNO3 after treatment with DNA-degrading enzymes, thus also showing the ability of the LDH host to protect the intercalated biomaterial from degradation. Cell transfection studies on Vero3 cells were then performed, where cells transfected with the nanobiocomposite exhibited fluorescence as early as 12 h post-treatment compared to naked delivery of the plasmid itself