Vectorial Role Of Anopheles Subpictus By Using Poymerase Chain Reaction
Material type: Book ; Format:
; Literary form:
Publisher: 2014 Dissertation note: Vector-borne diseases are among the major causes of illness, death and economic losses particularly in tropical and subtropical areas of the world. Mosquitoes are most important single group of insects, transmitting wide range of human diseases like malaria, Japanese encephalitis, dengue fever, yellow fever, filariasis and several other infectious diseases. Malaria is a major global public health problem. Several Anopheline species are prevalent in Pakistan among which Anopheles stephensi and Anopheles culicifacies are confirmed vector of Plasmodium. An. subpictus is a confirmed secondary vector of malaria in many countries. A wide range of this species is also distributed in Pakistan. The aim of the present study was to determine the vectorial role of An. subpictus in the transmission of malaria in Pakistan through microscopy and polymerase chain reaction (PCR).
After species identification, the mosquitoes were examined microscopically and were found negative for the presence of human Plasmodium sporozoites. The DNA extracted from An. subpictus was subjected to PCR but no Plasmodium specific amplification was observed. Keeping in view the sample size, it was concluded that further study is required with even large sample size before declaring that An. subpictus is not a vector of Plasmodium in Pakistan.
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Anticoccidial Activity Of Aloe Vera (Qawar Gandal) In Broiler
Material type: Book ; Literary form:
Publisher: 2014 Dissertation note: There are various species of Eimeria that cause coccidiosis. This disease is considered to be one of the most significant and prevalent diseases across the world. This disease reduces the production and causes high morbidity and death rates, on the other hand for controlling this eimeriosis, one has to adopt preventive therapy in the form of anticoccidial drugs in combination with occurrence of natural immunity in birds. Coccidia cause infection in intestine and multiply in gut and belong to protozoan parasites. These protozoan coccidian cause chicken Eimeriosis which is considered one of the most significant diseases, that cause severe economic losses across the world. For poultry control houses, coccidiosis is considered one of the most common (Hamidinejat et al., 2010).
As oocysts of coccidia are very unique so they spread from one poultry farm to another poultry farm and for dissemination of this protozoan, parasitic disease management plays a pivotal role. Now it’s very hard to keep chickens safe from these parasitic protozoa particularly in the control poultry houses where high production is required. In poultry house litter, oocycts multiply readily. But there are some factors which affect the number of these protozoa like bacteria or some environmental factors like liberation of Ammonia gases and under these factors, Eimeria start to diminish after three weeks (Williams, 1995).
Caecal and intestinal forms are the two important forms of avian coccidiosis. Diarrhoea and excessive caecal haemorrhages are the main symptoms of caecal coccidiosis and its causative agent is Eimeria tenella (Gardinar 1955). In prevention, surveillance and control of coccidiosis specific diagnosis plays a pivotal role. Eimeria oocysts from the faeces of infected chickens have been detected or enumerated by conventional methods and pathological lesions resulted by Eimeria infection and oocyst structure can also be determined by employing traditional methods (Long and Joyner 1984). But because of the involvement of multiple species of Eimeria in coccidial infection these approaches cannot be realistic as there can be overlapping among various sizes of oocysts (Long and Joyner 1984).
There are six species of Eimeria which cause great economic loss in chickens and also these species are highly host specific. High mortality rate and morbidity rate due to bloody enteritis and production losses are reasons of great economic. Despite management now a days anticoccidial drugs have been used in chicken feed to minimize the effect of this disease. E. tenella, E. necatrix, E acervulina, E. maxima, E. brunetti , E. mitis and E. praecox are the seven species of Eimeria which are considered as main causative agents of coccidiosis in chicken (Arabkhazaeli et al. 2011).
However, control of coccidiosis can be achieved by producing species-specific natural immunity along with anticoccidial drugs (Shirley et al. 2004), but it’s also evident from the fact that drug resistance has been increasing due to excessive use of anticoccidial drugs (Williams 1998). Pathological lesions, host and protozoan characteristics are very important for diagnosis of coccidiosis. But one cannot identify the Eimeria species accurately as analysis of these characteristics requires high expertise.
Good management plays key role in controlling coccidiosis which includes proper ventilation, dry litter, drinkers and feeders in good clean condition and appropriate density of stock (Jordan 1995, Gross 1985). Size and morphology of parasite at various stages of life cycle plays an important role in identification of Eimeria and site of enteric pathological lesions. In complex infection it’s very hard to identify the species showing same features (Long and Reid 1982).
The increasing resistance of avian coccidiosis to anti-coccidial drugs currently used by poultry industry together with the requirement for drug and the production systems which should be antibiotic free, it’s now very necessary to go for the new and advanced methods to prevent from this disease. Therefore, scientists started to work on medicinal use of herbal products to control this eimeriosis. In past for treatment of various human and poultry ailments the natural herbal products have been effectively used several times. Because of the anticoccidial nature and antibacterial effect, Aloe vera could be served as a valuable alternative for coccidiostats as a medicinal plant. Previously aloe gel has been used for multipurpose like as an antibiotic, for healing of wounds, for anti-inflammatory effects, for anti Eimerial response and as an anti-ulcer agent. It was also reported that in broilers it increases immunity by enhancing the number of microvilli (Jinag et al., 2005). In Asia Aloe gel is considered one of the most common and easily available country medicines to get effective deliberate results. Therefore, the current study planned to cope coccidial diseases in broilers by serving Aloe vera as an effective weapon.
The present study therefore planned to discover the anti-coccidial effects of Aloe vera in broilers by using its powdered form, aqueous and methanol extracts.
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