216 research outputs found
The Toxicity Of Brachiaria Detimbens
Nine healthy adult Indigenous Sheep of Malaysia (ISM) of
which four were rumen fistulated were allowed to graze on a
hactare of pure stands of Brachiaria decumbens. The animals
developed signs of photosensitization, jaundice, and even death
within three to four weeks. Occasionally signs pertaining to
nervous dysfunction and submandibular edema were also observed. By
the end of the ninth week there were no survivors. Their serum
AST, GLDH, BUN, creatinire, bilirubin (total and direct) rose
prcgressively thru:ghout the entire period of study. There was evidence of neutroIililic leucocytosis with the absence of toxic
neutrophi is and the absence of haemolyticcris is in the
intoxicated animals.
Rumina l stasis occurred approximately three weeks postgrazirg.
The gross, histolcgical and ultrastructural charges in
the livers and kidneys indicated presence of necrosis and
degeneration.
Three healthy adult rumen fistulated Australian Milking Zebu
(ALT) bulls fed decumbens for nine weeks did not develop any
evidence of toxicosis either clinically or clinicopathologically
as that seen in the sheep
Meandering through the superb scientific world of pathology: exploring intrapolations
Although literally pathology can be defined as the “study of sufferings”, it by no means signifies that a pathologist benefits by seeing an individual enduring pain from an ailment. In fact, many regard pathology as the turning point of life and it is usually dubbed as “The field where herein death rejoices to aid the living”. Indeed, a very true slogan since pathology assists in explaining the cause and mechanism of death. Through this process of pathogenesis or pathophysiology, the outcome (between the interaction of host, environment and agent) is used to develop an effective treatment, control and prevention regime. An old branch of biological science, pathology works closely with the other “physical” components of chemistry and physics to elucidate an abnormality. The needs of these two physical science components is inevitable in explaining pathologies dealing with haemodynamics of blood flow, aerodynamics of particulates, phagocytic activity, metabolic derangements, action potential, forensic investigation and many others. In actual fact, it forms the backbone of Koch’s postulate which, currently, either willingly or otherwise, is used in most biological research models. This includes that of infectious (from the novel prion to naked-eye parasites), metabolic, endocrinebased or toxic (all forms) origin. Most biomedical-based research relies on inventing a functional model of a disease or condition. This can only be conclusively verified using pathology where even failure to elicit biochemical changes by the body can be detected at either the microscopic or ultrastructural level. Currently, many regard pathology as a study of pre-disease condition where through biopsies, an effective treatment, control, prevention and a prognosis can be derived.
Furthermore, pathology at almost all levels, is the only field that can state if a change in a tissue is a lesion, artifact or post mortem effect. This is of utmost importance in both research and forensic investigation. Nevertheless, despite no changes or new additions made in the terminologies used, it still remains valid and has kept itself abreast with developments in molecular and nanotechnological sciences. This has given rise to the birth of many newer branches of pathology that employ molecular techniques and nanotechnology in arriving at a confirmed diagnosis. In the medical context, the historic notion that pathology is involved with death or post mortem is currently irrelevant as mentioned earlier, since it has been successfully exploited to detect states of pre-disease conditions.
Likewise in research, pathology is not just a tool but rather an inevitable adjunct for excellence where a postulated functional model is being proven. Indirectly, while known to be associated with a non-living soul, a pathologist is an indispensable research partner in many of today’s research. This review will try to illustrate the significance of the meandering path taken by pathology in the ever changing world of research and diagnosis. Examples used will be those encountered in our quest to solve problems in toxicology, forensics, environmental pollution, emerging and re-emerging diseases and the development of new nutraceutical products. It is clearly discernible that pathology was, is and will still remain as an important component in most biological science research as will be exemplified in this review.
Pathology has helped many to achieve breakthroughs in toxicology, forensic science, environmental issues, nutraceutical and transboundary disease investigations. In Brachiaria decumbens toxicity, the mechanism of liver damage and associated signs were elucidated. The use of pathology in forensic investigation attempted to estimate the time of death following the advent of virtopsy in the veterinary field. It was found that the air pollutants, especially that of PM2.5, can lead to acute and chronic changes in the lung while garlic and blackseed can alleviate these changes. Zerumbone is an effective compound that could reverse artheroscelerotic changes
Immunosuppressive effects of benzo (a) pyrene on Newcastle disease vaccination in broilers
Newcastle disease (ND) vaccination was used as a model in assessing the role of benzo(a)pyrene (BaP) in inducing immunosuppression. Forty day-old chicks were divided into a control and BaP group comprising of 20 birds each. The control group was instilled with tricaprylin alone while that of BaP received 15 mg BaP/kg intratracheally for 5 consecutive days. Live ND vaccine was given on Day 7 and repeated again on Day 21 to all chickens. Prior to post mortem, blood was collected from five chickens from each group at Days 0, 7, 14, 21 and 35 for determination of HI titer. At necropsy, liver and lung samples were procured for the determination of glutathione transferase (GST), glutathione peroxidase (GPx) and malionaldehyde (MDA) activities. The BaP group gained a slower immune protective level compared to that of the control (21 versus 7 days). The hepatic and pulmonary GST activity and MDA level of the BaP group demonstrated an increment until Day 14 p.i. which then tapered towards the end of study. However, the GPX activity was only invoked towards that later stage of the experiment. Likewise, it was also shown that the GST and GPX activities were negatively correlated. Thus, this study unveiled that the metabolism of intra-tracheally instilled BaP brings about systemic oxidative stress which induces immunosuppression in broilers
Induction of immunosuppression by benzo (a) pyrene in broilers
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon which has shown carcinogenic, teratogenic, mutagenic and claimed immune-suppressive potentials. However, the exact mechanism whereby BaP induces such immunotoxicity is not fully explored. The effect of BaP on the immune system and morphology of selected lymphoid organs of broilers were investigated. Forty day-old chicks were divided into control and BaP groups compromising of 20 birds each. The control group was instilled with tricaprylin only while the other received 15 mg BaP/kg intra-tracheally for 5 consecutive days. Live ND vaccine (La Sota strain) was given on Days 7 and 21 to all chickens. Five chickens from each group were sacrificed via cervical dislocation and the liver, lung and lymphoid organs were collected at Days 7, 14, 21 and 35. Tissues were subjected to assay for cytochrome P450 (CYP1), SOD and MDA. In this study, marked expression of CYP1 in the broilers denoted the sensitivity of broilers to BaP exposure. Such expression has in turn led to oxidative stress which led to immune-supression via damage of lymphoid organs. This warrants judicious assessment of poultry health status with respect to the occurrence of haze or air pollution episodes. Effective immune-modulatory strategies will render adequate flock health and translate maximum profit to the farm
Cloves protect the heart, liver and lens of diabetic rats
Clove oil was previously reported to modulate physiological responses in streptozotocin-induced diabetic rats. This study attempts to evaluate the in vivo organ and tissue protective effects of dietary cloves (Eugenia aromaticum) in chronic hyperglycaemia. The cloves (equivalent to 100 mg total eugenol + eugenyl acetate per kg body weight/day) were administered orally to streptozotocin-induced diabetic male Sprague-Dawley rats. Fasting blood glucose levels, as well as organ tissue physical and biochemical markers, were monitored. Dietary supplementation with cloves reduced tissue injuries, especially in the lens and cardiac muscles, and to a lesser extent in the liver but not the kidneys. Additionally, the cloves treatment significantly reduced blood sugar increases and lipid peroxidation in streptozotocin-induced diabetic rats by restoring the antioxidant enzyme levels. Cloves inhibited hyperglycaemia-induced oxidative tissue damage and cataract formation in the eye lens. This study demonstrates the in vivo antioxidative organ protective effects of clove in diabetics
Prevalence, gross and histopathological findings in the lungs of suspected heartworm infected cats in the Klang Valley, Malaysia
Feline heartworm disease is a potentially life-threatening disease of cats that most commonly manifests as heartworm-associated respiratory disease (HARD). Unlike canine heartworm disease, antemortem diagnosis is difficult due to low worm burdens, frequency of all male infections, and non-specific radiographic lesions. Thus, a combination of tests must be carried out and interpreted with care in order to make an accurate diagnosis of feline heartworm disease. Feline heartworm disease has yet to be studied in Malaysia, therefore there was a dire need to investigate and determine the prevalence rate of this disease in the country. Fifty cats comprising 14 strays and 36 pets were included in this study. Serological tests for antigen and antibody (SNAP® IDEXX and Heska ® Solo Step® FH respectively), was performed for all the samples. Knott’s concentration technique, thoracic radiography, followed by necropsy and histopathology were also carried out for the stray cats. Feline heartworm disease was not detected following Knott’s concentration technique or serological testing in the stray cat population. None of the pet cats were positive for feline heartworm disease following serological testing. The most common thoracic radiographic findings in the stray cats were interstitial and bronchoalveolar patterns of the lungs. The most common findings upon necropsy and histopathology included pulmonary oedema and pulmonary congestion and haemorrhage. Since there were no positive feline heartworm disease cases detected, no associations could be made between the radiographic and histopathologic findings and feline heartworm disease. The overall prevalence rate of feline heartworm disease in the Klang Valley, Malaysia was 0%
Algor mortis pattern in dogs, a guide to estimation of time of death
Although differing methods of estimation of time of death in human forensics have been well documented, there exists paucity of information in the veterinary field. With little accuracy, veterinary pathologists rely on gross post-mortem changes which include autolysis, rigor mortis, livor mortis, and putrefaction in estimating time of death in animals. This study assessed the pattern of temperature drop in six mongrel dogs using commonly available thermometer. Rectal and hepatic temperatures were taken for eight to eleven hours after death at an average ambient temperature of 29 °C (24 °C to 34 °C). Both organs revealed strong regression models which were harnessed to provide a mathematical guide to estimating time of death in the early hours (six to seven hours). Linear model of temperature drop pattern change was considered less cumbersome for field use. The rates of drop were extremely irregular during the study period. This work substantiates the use of algor mortis as an adjunct in estimating time of death in dogs
Pulmonary lesions associated with intratracheal Benzo(a)pyrene instillation in Sprague Dawley rats
This study was conducted to assess acute exposure to very low dose of intratracheally instilled Benzo(a)pyrene (BaP) on the lungs of rats. A total of 30 rats were utilized in this study and they were randomly divided into 6 groups. The control group (G1) did not receive any treatment, whereas the rats in the remaining 5 groups were administered with 13.8 ng of BaP, which were then sacrificed at 1 hour (G2), 8 hours (G3), 16 hours (G4), 32 hours (G5), and 72 hours (G6) of post-instillation (p.i.). Morphological appearances of all the lungs of all the treated rats consisted of various degrees of congestion, mostly evident in G3 and early development of emphysema, as seen in G4. These worsened as time progressed as observed in G6. On the other hand, the histological findings of the lungs of the treated rats revealed that the lungs had underwent some changes that were characterized by progressive alveolar congestion, epithelialisation with emphysema and accompanied by infiltration of inflammatory cells predominantly with alveolar macrophages and some neutrophils. However, even with such lesions seen, there was no apparent manifestation of impairment of the pulmonary system
Selenium status in beef and dairy cattle at Taman Pertanian Universiti, Universiti Putra Malaysia
Selenium (Se) nutrition forms an integral part of growth and immune function of man and animals. Deficiency of Se in cattle will inevitably lead to poor growth and mastitis causing an economic loss to a farm. This study was carried out to determine the level of Se in beef cattle and dairy cattle reared at the Taman Pertanian Universiti, Universiti Putra Malaysia. A total of 27 dairy and 36 beef cattle were randomly chosen in this study. The age of the cattle used ranged from 1 to 9 years old comprising of both sexes. Blood sample was collected into heparinized and plain tubes for the detection of glutathione peroxidase (GSH-Px) activity and aspartate aminotransferase (AST), creatine kinase (CK) and malonylaldehyde (MDA) concentrations, respectively. The activity of GSH-Px was detected using the dithio-bi-nitrobenzoic acid (DTNB) direct method assay. The concentrations of AST and CK were determined using standard diagnostic kits, while the MDA using the TBA (thio-barbituric acid) test. It was found that although no significant differences existed in the GSH-Px activity between breeds, their Se status were in the deficient state. This is in line with previous reports that the acidic soil of Malaysia renders low Se uptake by plants leading to deficiency state in grazing ruminants. The concentrations of AST and CK were higher in beef cattle due to much more overt muscular damage as the result of foraging and lack of supplementation compared to dairy cattle. It is suggested that diet of both breeds should be supplemented with Se to prevent such deficient status in order to increase the productivity of the farm
- …