TheVetMed

Cells of Immune System

2019-12-14T17:11:00.000+05:30

Leukocytes

They are responsible for both specific and non specific immunity.

Leuko-white ; cytes- cells

They are originated from pluripotent stem cells in the liver

There are two types of leukocytes based on presence of nucleus.

Agranulocytes: cell without granules .It have two types

Monocytes, Lymphocytes

Monocytes

Single-cell,

Kidney shaped nucleus,

Produced in bone marrow,

The mature form of monocytes is called Macrophage.

Monocytes – Circulate in the blood.

Macrophages –Circulate in the tissues.

Macrophage is useful to carry out Phagocytosis.

Lymphocytes

Divided into 3 types: T cell, B cell & NK cell

B lymphocytes or B cell - mature in bone marrow-circulates in the blood-reach to various lymphatic organs & Activated

This activated mature B cell is called Plasma cells.

Plasma cell secretes large quantity of glycoprotein which is called Antibodies.

T- lymphocytes or T- cell

It is produced in Thymus gland-circulate in the blood-reach to the lymphatic organs

It requires Specific antigen to bind

It do not secretes antibody

Activated T cell produced & secretes some proteins called Cytokines.

Natural Killer (NK) cells

They play important role in cell cytotoxicity.

They also play important role in innate immune response

They are non-phagocytic cells

2. Granulocytes or Polymorphonuclear (PMN) Leukocytes

A group of white blood cells is collectively referred to as granulocytes or Polymorphonuclear leukocytes (PMNs).

Granulocytes are composed of three cell types as

Neutrophils, Eosinophils, Basophils.

These cells are important in the removal of bacteria and parasites from the body.

They engulf these foreign bodies and degrade them using their powerful enzymes.

Neutrophils

Neutrophils constitutes 50-70% of the circulating WBC’s.

Life span 2-4 days in tissue.

They are first cell to arrive to the infection site.

It plays important role in inflammatory response.

Phagocytic and bactericidal.

Leucocytosis

Eosinophils

Eosinophil constitutes 1-3 % of the circulating WBC’s.

Important in anti-parasite defences.

It presents Antigen to T cell in body.

Release of contents present in Eosinophils can damage the parasite membrane.

Eosinophils are associated with allergic diseases.

Basophils

Only present in the bloodstream, and represent <1% of circulating WBC.

They are non-Phagocytic cells.

They play a major role in the allergic response.

They release their granules (containing histamine, serotonin, heparin, prostaglandin, etc into the bloodstream following exposure to specific allergens).

When an individual is exposed to an allergen, specific IgE is produced. This IgE binds to the surface of basophils.

Mast cells

Mast cells are released from the bone marrow as undifferentiated precursor cells and do not differentiate until they enter the tissues (skin, connective tissue, mucosal epithelium, etc.)

Play a very important role in the development of allergic response.

They produce a variety of cytokines.

Dendritic cells

Originate in the bone marrow

Function as antigen presenting cells (APC).

Four types of dendritic cells are – Langerhan’s cells, Interstitial dendritic cells, Myeloid cells, Lymphoid dendritic cells.

-Siddhi Shah

Recent advancements adopted in veterinary science from medical field

2019-10-05T01:14:00.000+05:30

Veterinary Science is a long back ancient science of “Mahabharata” and “Charak yug” time. That much old science we are bringing it, till now with more or less advancement. In 21^st century, Veterinary Science gets flourished with the discovery and invention of different techniques, methods, and advancement in facilities that make veterinarians able to do work very efficiently and perfectly. The darker side of this science is only that it is always growing up as a shadow of medical science. The advancement of the medical filed almost adapted in veterinary practice. Veterinarian job is not an easy task to perform in the filed level. The inventor and researcher are always in the way of finding the further new thing to make the medical as well as veterinary science very reliable and very efficient to do work. As there is different classification in the both science, advancements are also get divided according to that. The majorly there are three classes, viz. Clinical, Para clinical and Basic science. Each class has their benefits and contribution in the field. Majorly the clinical side always get bias in terms of facilities because its value, important and field applicability by treating the animal.

Recently in clinical science there are MRI, Pet Scan, CT scan, 3D stereotactic biopsy technique, digital encephalography, cardiography and robotic guided surgical intervention support of diagnostic aid have taken place in veterinary field, too. These diagnostics aid make veterinarian easy to diagnose related conditions. Similarly, there are many surgeries like, heart- cardio vascular surgeries like valve replacement, stent adoption pacemaker adoption and many more, CNS surgical intervention, Transplantation surgeries and many more challenging surgeries still not adapted in field due to many reasons like, undiagnosed, owner disagreement, vet skill, surgeries aided supportive and post-operative care and many more. Though focally in some place, couple of surgeries have perform due to their advancement in technicality, facilities and skills. These were reported to be adapted from medical field. Cataract surgeries, retinal intervention as well as endoscopic and laparoscopic guided intervention have been adapted with the medical collaboration. There are lot to do and adapt from medical field in terms of clinical hand, clinical advancement, facilities procurement from medical. In short, in recent times the clinical part of veterinary filed has tried to selective adaptation of technologies as well as the skill to do that. Though it was not completely but in the way to achieve.

By the time we have independently also developed and commercializes many clinical aided technique and method. Digitalization of per rectal examination of ovary, uterus and all reproductive organ can be aided by tiny hand cuff foldable screen and camera guided instrument. Similarly, different test has been also we have developed for clinical support. Some surgeries which are also independently we are performing and developing in that by adopting the medical field. The basic surgical principle is organized and well established which make both field surgeon efficient and independent of each other at basics. Hormonal treatment of ovulation synchronization has been completely adopted by medical gynecology, now it is mostly flourishing in veterinary by independently modification and advancing into the techniques. Even Medical filed have adopted many technique from veterinary science.

Para clinical and basic science mostly dependent on animal science. The use of laboratory animal is mostly for the medical advancement. Drug discovery, Drug trial, Drug applicability, Vaccine development, hormonal preparation, as well as any kind of new discovery can’t take place without help of experimental and lab animal. This is only the part of medical research and development, where they are doing adaptation by first experimenting on animal. The animal aided research help to medical field as well as veterinary for better health and better life. Here only medical field are totally reliable on animal. Though advancement and discovery in terms of disease diagnosis are may occur independently. Disease diagnostic aid like PCR techniques, Blotting technique, Gel electrophoresis, ELISA, Biopsy, Histopathology and many more disease diagnostic techniques are similarly used in medical and veterinary. Digitalization of histopathological imaging technique make pathologist easy to diagnose. As, these invention and discovery helps both the science, it was similarly used. Recently, Genome editing CRISPR/Cas9 technique adopted in medical field but still we are lagging in adopting it for disease diagnosis, vaccine and genome editing. If gene-editing technique adapted in veterinary field, the day is not so far where we have “mastitis resistant” livestock. We can establish our livestock by modifying the mastitis causing bacterial gene and the genetic makeup of our livestock. Hopefully the veterinarian scientist come up with the filed establishment and its applicability.

In general, if we look both science, we are dependent on each other, without help of both sciences it won’t possible of advancement of human and animal health. We are interdisciplinary nerve and blood vessel connected cloud which can’t be possible by connection at both end side. As I have narrated, clinical diagnostic aid we have adapted very well. MRI, CT scan, digitalized computerized guided surgeries have been adapted so far in veterinary field, too. However, we are at some point of technology adaptation far behind due to the hurdles, otherwise, veterinary field has also flourished in well manner to support the livestock owner and our farmer.

Colibacillosis in poultry: A major economic threat for poultry farmers

2019-10-03T12:25:00.000+05:30

INTRODUCTION

Avian colibacillosis called to the any localized or systemic infection that caused entirely or partly by avian pathogenic Escherichia coli (APEC), including colisepticaemia, coligranuloma (Hjarre’s disease), air sac disease, swollenhead syndrome, venereal colibacillosis and coliform cellulitis, peritonitis, salphingitis, orchitis, osteomyelitis/synovitis, panopthalmitis, omphalitis/yolk sac infection and enteritis as there are different pathotypes. Avian colibacillosis is an infectious and economic threat disease of birds caused by Escherichia coli (E. coli) which is considered as one of the major causes of morbidity and mortality, associated with heavy economic losses to the poultry industry by its association with various disease conditions, either as primary pathogen or as a secondary pathogen like Mycoplasma spp., and various fungi.

Host

Clinically defined disease is reported most often in chickens, turkeys and ducks only. colibacillosis form of disease is most commonly seen in broiler chickens. It is majorly responsible for both embryo as well as early chick mortality even in breeders, too.

Risk factors

Factors associated with occurrence of avian colibacillosis are many Age is major factor of causing diseases. All age birds are susceptible to colibacillosis, but young birds are more frequently affected and severity of the disease is greater noticed in young birds. Most of the outbreaks of colibacillosis occur around the period of peak production even sometimes at early age due to environment and water. Environment is one of the major crucial role for poultry rearing and its management. Similarly, water supply to birds is major risk factor, as it directly caused the disease.

Clinical signs

Although, with the technically, death is not a clinical sign in colibacillosis, this may be the main indication of an outbreak of colibacillosis in a flock. But it can caused the death due to the septic cause which may callled as colisepticemia. Clinical signs of predisposing or compounding factors are seen concurrently with signs of E. coli infections.

Gross lesions

Gross lesions can be found after post mortem examination are characteristic of colisepticaemia/colibacillosis in birds inclusive of fibrinous perihepatitis, pericarditis, congestion and regression of ovarian follicles with thicked tracheal and bronchial plug deposition.

Diagnosis

Collection of samples

The diagnosis of colibacillosis iscan be done by isolation of E.coli from cardiac blood and affected tissues like liver, spleen, pericardium, bone marrow. Bone marrow cultures are easy to obtain it and are generally free of contaminating bacteria. Swabs collected from liver, oviduct and body cavity were also used for isolation of E. coli from colibacillosis infected birds.

Isolation and identification

E.coli can be identified primarily as gram negative rods by Gram staining technique. Selective media like MacConkey, eosinmethylene blue (EMB) and HiChrome E. coli agar(HiMedia, India) are used for isolation of E. coli. A presumptive diagnosis of E. coli infection can be made if most of the colonies are characteristically dark with metallic sheen colour on EMB agar, bright pink with precipitate surrounding colonies on MacConkey agar, greenish colour colonies on Hichrome agar. Further identification of the isolated colonies is based on biochemical reactions like, indole production, fermentation of glucose with gas production, presence of betagalactosidase, absence of hydrogen sulphide production and urease, and the inability to utilize citrate as carbon source. Molecular confirmative diagnosis can be made by the E.coli 16S rRNA based Polymerase chain reaction.

Economic losses

Colibacillosis is one of the major causes of economic loss in the poultry industry worldwide. Despite being known for its impact, avian colibacillosis remains one of the major endemic diseases of poultry resulting in decrease in productivity, mortality and economic losses. About 5.5 per cent mortality and 10-20 per cent drop in eggs was observed with E. coli infections in egg type layers reared in cages. Heavy economic loss occurs in colibacillosis affected broilers and layers due to morbidity and mortality, which reduced production and poor chick quality. It has reported by Omer et al. that colibacillosis in layers caused 1.9 per cent mortality, results in 824.6 US $ economic loss in layers.