Toxicopathological Alterations And Tissue Residue Of Colistinsulphate (Polymixin E) In Broilers
Material type: Book ; Literary form:
Publisher: 2014 Dissertation note: Poultry industry is the 2nd largest industry in Pakistan playing important role to meet daily protein requirement with an investment of more than 200 billion rupees. It is contributing 6.1% and 10.8% share in total contribution of agriculture and livestock the national GDP, respectively. Total poultry meat production in the last year was 987 thousand tones (Economic survey of Pakistan 2013-2014). Because of high density and lack of biosecurity measures, outbreaks of infectious disease are more common and often occurs. Different antibiotics are used rational and irrational to treat and control these outbreaks. Colistin is among the most widely used antibiotic in intensive poultry farming, it is used to combat gram negative bacterial infections particularly for collibacillosis and gastrointestinal tract infections (Hussain and Khalil 2013).
Colistin belongs to the polymixins group of antibiotics. It is also known as Polymixin E. Polymixins are structurally related substances consisting of a cyclic peptide with a hydrophobic tail, mainly produced from gram positive nitrogen fixing bacteria Bacillus polymyxa. Polymixins are classified into six subtypes namely polymixin A to F and among these polymixin B and E are commonly used for the treatment of gram negative infections in animal and human beings. Colistin is mixture of two subtype’s colistin A (polymixin E1) and colistin B (polymixin E2). Commercially, it is available in two forms colistin sulfate and colistimethate sodium but colistin sulfate is more stable cationic water soluble salt (Landman et al. 2000) and is easily available in markets.
colistin sulphate has lipophilic and lipophobic(hydrophilic) properties, that makes it easier to interact on bacterial cell membrane by displacing counter ions in lipopolysaccharides, influencing Mg efflux that’s why it is effective against gram negative bacteria (Poole and Sheffield 2013). Polymixins also presents antipyretic activity by binding endotoxins, especially lipid A, (the active compound of lipopolysaccharide). Owing to this property it is extensively used to treat gram negative infections in livestock and poultry industries (Hanasawa et al. 1990).
The use of colistin was restricted in the past due to its toxic properties mainly in nephrotoxicity. There are reports available in the literature indicating that the parental use of colistin leads to the alterations of biochemical parameters in chicken i.e. increase in glutamic oxaloacetic transaminase, catalase activity, creatinine while, adversely affect total plasma proteins (Ibrahin et al. 2011). In ostriches it leads to the development of neurotoxic signs along with histologically odema formation in pericardium, intestinal serosa and heart was observed (Landman et al. 2000).
Toxic effects of colistin were also reported in humans including nephrotoxicity, increased serum creatinine during the treatment (Falagas et al. 2005). As bioavailability for oral route is minimal and it is used parentally to treat systemic infections. Parenteral route may cause toxopathological effects in birds. Other effects includes change in aspartate aminotransferase and alanine aminotransferase which indicate liver damage. Red blood cells, white blood cells, packed cell volume and hemoglobin estimation were also decreased (Saleemi et al. 2013). The incidence of nephrotoxicity is severe but less common in oral administration as polymixins absorption through gastrointestinal tract is very slow and limited, and cannot be detected in plasma concentrations at ordinary doses (Falagas and Kasiakou 2006). Instead of all these toxic effects, now a days it is frequently used for the treatment against gram negative bacterial infections (Vaara 2010).
The emergence of bacterial resistance has become an important public health hazard throughout the world). Due to irrational use of antimicrobial drugs against different diseases (Naqvi et al.2013. Colistin is one of the most widely used antibiotic in poultry industry against diseases like collibacillosis, salmonellosis and clostridial infections through drinking water, feed additives and parenteral route in developing countries like Pakistan (Tanweer et al.2013). Parenteral use of colistin sulphate may leads to the deposition of residues in different tissues. The presence of its residues in edible parts may lead to the toxicity as well as development of antibacterial resistance in human.
Keeping in view the potential toxic effects and other hazards relating to the extensive use of colistin in poultry birds, present study has been designed to investigate dose dependent patho-morphological alterations and tissue residue in broiler chickens.
1. To study the toxicopathological effects of parenteral administration of colistin in broilers.
2.Investigation of the tissue deposition of colistin as residues and its withdrawal period.
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Seroprevalence Of Brucellosis In Ruminants At Sale And Purchase Markets And Abattoirs In Three Selected Districts Of Punjab, Pakistan
Material type: Book ; Literary form:
Publisher: 2016 Dissertation note: This is a representative study from Pakistan accompanied in three districts of
Punjab i.e. Jhang, Layyah and Toba Tek Singh which are rich in livestock population.
There is a lot of research work on livestock farms but the sale and purchase markets and
abattoirs are neglected. Pakistan is an agricultural country and livestock contribute a major
share to agriculture in Pakistan GDP and its economy. Sheep, goats, cattle and buffaloes
contribute in the economy of Pakistani people by milk and meat production on majority
basis. Livestock contribution to the agriculture value added is 56.3%, while it contributes
11.9% to the national GDP during 2014-15. More than 8.0 million rural families of the
country are involved in raising livestock. But productivity of livestock is questioned by a
lot of factors. Infectious zoonotic diseases are among these.
Brucellosis is one of the major and unreported problem amongst livestock markets
and abattoirs of our country. It results in losses to the economics of the farmers or owners
in terms of poor health, abortions, long calving interval, production of weak offsprings and
deprived quality of milk and meat. This disease is under investigated and hence people are
unaware of this deceptive problem. Serological surveillance is a good and cheaper tool to
diagnose this problem. Determination of the seroprevalence is important to know the load
of disease and pockets of infections in the area of Punjab, Pakistan. There is also a need to
know which diagnostic antigen is more sensitive and specific from disease eradication and
control point of view.
A total of 300 animals serum samples were collected from three districts of the
Punjab province and tested by conventional screening test i.e. Rose Bengal Plate
Agglutination Test (RBPT) by using two antigens of different countries origin i.e. VRI
(Lahore, Pakistan), IDEXX (Pourquier, France) and ID.vet, France and then tested with
indirect Enzyme-linked Immunosorbent Assay (iELISA). The data thus obtained regarding
seroprevalence was analyzed using Chi-square SPSS version -19 (Nahar et al. 2009).
Of the total 300 animals (77 male and 223 female), 1.3% male and 35.66% female
were seropositive for anti-Brucella antibodies. Different risk factors were also included in
study like sex, area, age, gender, abortion, reproductive problems and also history of orchitis
in male. All of these risk factors were statistically analyzed to reveal the truth about ruminants
brucellosis. Among the various risk factors studied, the risk factors including history of
abortion (16.44%), orchitis (1.3%), retained placenta (26.47%), species cattle (35.55%) and in
Toba Tek Singh (47.36%) were statistically significant which could be potential source of
threat for humans and other animals. The testing was performed using conventional methods
as well as using iELISA. It is concluded that iELISA is more sensitive and specific than
conventional screening tests but molecular diagnosis is highly recommended for future
studies. The current study will help to minimize and eradicate the low prevalence of ruminants
brucellosis by creating awareness between the farmers and through vaccination and herd
immunization. By implementing the policy of testing and culling of positive reactors will be
pivotal to achieve the objectives.
For confirmatory diagnosis all the sera were further tested with iELISA. For this
purpose an exclusive commercially available iELISA Kit (ID.vet, France) was used which
would be able to differentiate anti-Brucella antibodies of B. abortus and B. melitensis and this
iELISA kit would be able to be used for multispecies including cattle, buffaloes, sheep and
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The Effect Of Freeze Dried Stabilizers On The Infectivity Of Newcastle Disease Virus
Material type: Book ; Format:
; Literary form:
Publisher: 2017 Dissertation note: Pakistan’s economy depends on agriculture and livestock. Poultry industry of Pakistan is
playing an important role in livestock. One of the major problems due to viral disease is
Newcastle disease. Live vaccines are mostly available in lyophilized form to control the
Newcastle disease and can be produced on large scale at low cost, in which different types of
stabilizers are used but problem is that during the freeze drying process, storage and
transportation, the infectivity titre of the virus is lost, result reduced in efficacy of the vaccine.
The freeze dried stabilizers protects the virus from drying during lyophilization. They protect the
viruses from heat shock due to rise of temperature during vaccine transportation.
The freeze dried stabilizers in six combinations (Lactose-Skimmed Milk-Egg Albumin
LSE, Sucrose – Egg Yolk SE, Sucrose-Skimmed Milk- Egg Albumin SSE, Skimmed Milk SKM,
Wey-bridge Medium WBM and Sucrose-Skimmed Milk SSK) were used in ND Lasota vaccine.
Total 50 vials of each stabilizer were freeze dried and stored at 4-8 0C in dark. Three vials from
each set were proceeded for EID50 determination at day zero then every fortnight. The freeze
dried stabilizers LSE and SSE maintained the NDV stability with low reduction in mean
infectivity titre log 100.40 EID50 up-to 90 days. The mean infectivity titre of NDV vaccine for
both stabilizers was 106.93 then followed by SKM (10%Skimmed milk), SSK (5% Sucrose, 10%
Skimmed milk), WBM (2.5% Lactalbumin Hydrolysate, 5% Sucrose, 1% Monosodium
glutamate) and SE (5% sucrose, 30% Egg yolk). The freeze dried stabilizers SKM, WB and SSK
maintained the NDV stability with low reduction in mean infectivity titre log 100.34 EID50 up-to
60 days. The lowest stability was achieved by SE.
Availability: Items available for loan: UVAS Library [ Call number: 2821-T] (1).
Isolation & Identification of Different Bacteria of Public Health Importance from Cell Phones of Veterinary Professionals in Jhang, Pakistan.
Material type: Book ; Literary form:
Publisher: 2017 Dissertation note: CD not submitted.
Availability: Items available for loan: UVAS Library [ Call number: 2934-T] (1).