2.
Occurrence Of Bacterial Contaminants In Poultry Meals And Their Antibiotic Resistance Pattern
by Nayyab Tariq (2009-VA-207) | Prof. Dr. Aftab Ahmad Anjum | Dr. Muhammad Nawaz | Dr. Muhammad Nasir.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: Poultry is the second largest industry after textile industry in Pakistan. Its consumption
rate is very high as compared to other animal protein sources, as it is cheaper as compared to red
meat. To fulfill increasing demand of poultry, poultry production quality must be improved.
Many factors affect poultry production. One factor is feeding process. Efficiency of poultry
production depends mainly on feeding process which influences both the quality and quantity of
the poultry production (Grepay 2009). The rearing of poultry birds on commercial level requires
use of bulk quantities of poultry feed. Poultry feed costs 60-70% of total cost for production
(Sahraei et al. 2012). The main purpose to increase poultry production is to fulfill nutritional
requirements of human population that largely rely on poultry and poultry by products as a
source of protein(Obi and Ozugbo 2007).
Poultry feeds are food materials designed to contain all necessary feed ingredients for
proper growth, meat and egg production in birds (Obi and Ozugbo 2007). It is a mixture of
various components including plant proteins (cereals and by products, grains etc), animal byproducts,
fats, vitamins and minerals (Ravindran 2013). The major component of poultry feed is
protein which is the key component of eggs and meat. Protein sources in poultry feed are of
plant, marine and animal origin. Plant proteins may lack some of the essential amino acids, thus
are incomplete protein. Proteins of animal origin are better growth promoter than protein of plant
origin, but their safety is a concern. Among plant based proteins, soybean and canola meal are
produced in higher amounts worldwide (Alali et al. 2011). The animal protein sources include
poultry, fish, meat bone and poultry by products meal. Poultry meal is derived from clean tissues
Introduction
2
of slaughtered poultry including bone after the moisture and fat have been extracted in the
rendering process. It may contain whole birds excluding feathers (Anonymus 2014). Among all
protein based meals, poultry meals and poultry by products meal are of superior quality and
provide higher protein content than plant, marine and meat based meals (Samli et al. 2006).
Quality of animal feed has gained importance worldwide. The feeds are found to be
associated with infectious or non-infectious hazards, thus influence human health (Sherazi et al.
2015). Poultry feed can act as carrier of animal and human pathogens (Aliyu et al. 2012). Poultry
feed can get contaminated at any point of harvesting, processing, storage or dispersal of feed.
Primary mode of poultry feed contamination is by dust, soil, water and insects. Poultry meals can
be another source of feed contamination. Poultry meals are added in feed as a source of protein.
Feeds of animal origin like poultry meals are richer in nutrients and water as compared to feed of
plant origin thus are found to have higher microbial load, facilitating the multiplication of
bacteria (Kukier and Kwiatek 2011). Inclusion of contaminated meals in feed increases microbial
load of poultry feed. The contamination of poultry feed not only influences appearance and
nutritional value of feed, but also affects animals and human who consumes it (Maciorowski et
al. 2007). The profitability of poultry production can be greatly affected due to the frequency of
feed contamination and the detrimental effects of the aflatoxins on performance of chickens
(Anjum et al. 2011). Poultry feeds have been implicated in several poultry diseases of viral
(Avian Influenza, Newcastle disease), bacterial (Salmonellosis, Infectious Coryza) and fungal
origin. Many human diseases like Traveler’s Diarrhea and Salmonella Paratyphoid fever have
been associated with consumption of poultry birds that contracted infections from poultry feed
(Obi and Ozugbo 2007).
Introduction
3
The poultry industry relies on ready to use poultry feed prepared by feed mills (Arotupin
et al. 2007). Both bacteria and fungi including mycotoxins usually contaminate feed at different
stages of pre or post processing, depending upon the conditions under which it is handled or
stored (D’Mello 2006). Poultry meals mostly get contaminated post rendering process. The
cooking step in rendering process inactivates bacteria, viruses, protozoa, and parasites(Meeker
and Hamilton 2006) . Still presence of contaminants in meals is attributed to post processing
contamination. Many bacterial pathogens reported in feed are Escherichia coli, Erwinia
herbicola, Salmonella spp., Listeria spp., Enterococcus fecalis, Cl. perferingens and Cl.
botulinum (Aliyu et al. 2012; Lateef and Gueguim-Kana 2014) . The contaminated feed results
in excessive activation of immune system and ultimately decreases poultry production and its
profitability (Kukier et al. 2012). In addition to bacterial contaminants, toxigenic fungi have
threatened quality and safety of feed and have caused severe losses to poultry industry in recent
times. Cereals and grains based poultry feed mostly get contaminated with fungi (Kwiatek and
Kukier 2008). Mycotoxin producing fungal genera that are reported in poultry feed are
Aspergillus, Penicillium and Fusarium (Greco et al. 2014).
As Poultry feed is the first step of the food safety chain in "farm-to-fork" model. Contaminated
feed can also serve as a source of antimicrobial resistant bacteria in poultry meat(da Costa et al.
2007). There are many evidences that pathogens in feed are transmitted to humans through
animals and food of animal origin. It can also become source of some human pathogens in
environment. Feed contamination by fungi is responsible for animal mycotoxicoses and through
consumption of contaminated animal food, results in human intoxications (Kukier et al. 2012).
Birds utilizing toxins containing feed are economical loss for farmers and also affects consumer
Introduction
4
health through its residues (Alam et al. 2012). Poultry feeds containing antibiotic resistant
bacteria results in loss of poultry productivity, making treatment of poultry diseases difficult.
Thus quality of animal food directly depends on usage of nutritionally balanced and safe feed.
Among many feed sources used, poultry meals are gaining importance for their higher nutritional
value, but very less work has been done in world particularly in Pakistan to determine
microbiological safety of poultry meals produced. There is the need to determine various quality
parameters which should be followed to ensure production of safe meal. Availability: Items available for loan: UVAS Library [Call number: 2252-T] (1).
3.
In Vitro Activity Of Selected Biocides Against Fungal Isolates From Production Area Of Pharmaceutical Industry
by Sana Ilyas (2009-VA-238) | Dr. Muhammad Nawaz | Prof. Dr. Aftab Ahmad Anjum | Dr. Muhammad Ovais Omer.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Pakistan pharmaceutical industries have grown to grab their position amongst top ten pharmaceutical industries of Asia Pacific region. These are serving with 80% of pharmaceutical needs. The industry on the other hand faces some challenges in terms of sterile pharmaceutical product manufacturing. The fungal contamination causes spoilage to pharmaceutical products, cosmetics, and food products. The fungal contamination to pharmaceutical products has resulted in direct losses to human health and to economy.
A total of 50 air samples were collected from clean area of a pharmaceutical production unit by exposing sabouraud dextrose agar (SDA) plates by settle plate method (4 hours exposure). Fungal colonies were purified by sub-culturing and later identified macroscopically and microscopically. Selected biocides included isopropyl alcohol (70%), chloroxylenol (20%), chlorhexidine gluconate (20%), and benzalkonium chloride (20%) were used in this study. A 100 μl of spore suspension of each fungal contaminant (1.0 × 106 to 5.0 × 106 spores/mL) was exposed to 9.9 mL of biocide preparation for 15 and 30 minutes while exposure was stopped by adding 1 mL of mixture (spores exposed to biocide) into 9 mL of respective neutralizing agents The enumeration of colonies was started immediately after the growth was visible and expressed as Mean±S.D. and converted to log10. Antifungal activity of biocides was expressed as log10 reduction and different biocides‟ activity was compared using ANOVA technique by graphed prism 5.0 statistical software.
Total 204 colony forming units (CFU) were identified from filling area (36), solution room (47), and buffers (121). The antifungal activity in terms of log reduction was lowest by isopropyl alcohol at 15 minutes and highest was shown by chlorohexidine gluconate at 30 minutes against
Summary
64
Aspergillus flavus. In case of Aspergillus fumigatus all the biocides presented significant difference of antifungal activity at 15 minutes. The response of Aspergillus niger against different biocides at 15 minutes and 30 minutes was same as was in case of Aspergillus flavus while each biocide‟s antifungal activity was found significantly increased with increase in time of exposure. The similar response of antifungal activity of different biocides at both exposure times was noted against Saccharomyces cerevisiae. The antifungal activity of all biocides against penicillium was found significant different at 15 minutes and 30 minutes exposure time. Similarly, each biocide‟s antifungal activity increased with increase in time of exposure. On overall basis, isopropyl alcohol was found less effective while benzalkonium chloride and chlorohexidine gluconate presented comparatively higher efficacy against fungal isolates. Availability: Items available for loan: UVAS Library [Call number: 2705-T] (1).
