A Coronavirus infection of chickens, with much antigenic variation. The condition has a morbidity of 10-100% and mortality of 0-1%. Infection is via the conjunctiva or upper respiratory tract. There is rapid spread by contact, fomites or aerosol. A few birds are carriers up to 49 days post infection.
The virus is moderately resistant and may survive 4 weeks in premises. Poor ventilation and high density are predisposing factors.
Signs
* Drop in egg production (20-50%).
* Soft-shelled eggs.
* Rough shells.
* Loss of internal egg quality.
* Coughing, sneezing.
* Rales may or may not be present.
Post-mortem lesions
* Follicles flaccid.
* Yolk in peritoneal cavity (non-specific).
Diagnosis
3-5 passages in CE, HA-, typical lesions, FA. Serology: HI, SN, Elisa, DID. Differentiate from Egg Drop Syndrome, EDS76.
Treatment
Sodium salicylate 1gm/litre (acute phase) where permitted - antibiotics to control secondary colibacillosis (q.v.).
Prevention
Live vaccines of appropriate sero-type and attenuation, although reactions can occur depending on prior immunity, virulence, particle size (if sprayed) and general health status. Maternal immunity provides protection for 2-3 weeks. Humoral immunity appears 10-14 days post vaccination. Local immunity is the first line of defence.Cell-mediated immunity may also be important.
Extracted From:
A Pocket Guide to
Poultry Health
and
Disease
Order me a copy
By Paul McMullin
© 2004
Click Here to
Order Your Copy
Introduction
Wednesday, October 22, 2008
Infectious Bronchitis, IB Egg-layers
Thursday, June 12, 2008
A decontamination strategy to prevent mycotoxicosis
Mycotoxins comprise a structurally diverse family of naturally occurring, fungal-elaborated toxins, many of which have been strongly implicated as chemical progenitors of toxicity in man and animals.
The pathological states arising from the consumption of feeds contaminated with mycotoxins are termed mycotoxicoses. At high levels in feed, mycotoxins may cause loss or illness of farm animals, through development of animal toxicosis. At lower levels in feed these mycotoxins may have no apparent effect on livestock production, but their residue and related substances may move up the food chain.
The diagnosis of a mycotoxicosis is difficult because the effects observed are not necessarily unique to a given mycotoxin, but may be shared by other toxins and pathogenic organisms as well. Major criteria for making a thorough mycotoxicosis diagnosis include the following:
• Mycotoxin should be identified in toxin concentrations
• Pathogens should not be isolated
• Disease should not be infectious
• Animal performance should improve with contaminated feed withdraw
• Feeding suspicious feed to health animal should produce the same symptoms.
The main mycotoxin classes include aflatoxin, trichothecenes, fumonisin, zearalenone, ochratoxin, and ergot alkaloids. Most mycotoxins of concern are produced by three genera of fungi, namely, Aspergillus, Penicillium, and Fusarium. Fungal toxins produce a wide range of injurious effects in farm animals. Some of the clinical signs are presented in Table 1.
Decontamination strategies
Chronic exposure to mycotoxins not only alters animal performance but also exposure to mycotoxin contaminated feed could offer a great risk to public health. Practical and effective methods for controlling mycotoxin contaminated are urgent required.
Most common method utilized to protect animals against mycotoxicosis is the inclusion of various binding agents or sorbents in the feed. These materials prevent or diminish absorption of toxins in the Gastro Intestinal (GI) tract, reducing the transmission potential to the human food chain. The major advantages of these adsorbents include expense, safety, and easy administration through addition to animal feeds.
In vitro analysis of mycotoxin binders is a powerful tool for screening potensial sequestering agents. If a clay does not absorb a mycotoxin in vitro, it has little or no chance to do so in vivo. These lab techniques can be very useful in identifying potential dietary sequestering agents, and helping to determine the mechanisms and conditions favorable for sequestration to occur. The efficiency of adsorption of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), and fumonisin B1 (FB1) in solution at room temperature by Toxisorb is presented in Figure 1.
This study was conducted at the University of Munich, in Germany, In Vitro evaluation results suggested that Toxisorb is a strong binder for aflatoxin B1, ochratoxin A, zearalenone, and fumonisin B1.It is extremely important that any in vitro result be supported by in vivo experiments utilizing the species for which the product is intended, and with feed contaminated with levels of mycotoxins that are commonly found in the field. In vivo studies are needed to determine the stability of the complex formed in the gastrointestinal tract, and also to establish the harmless nature of these compounds. Predictions about the ability of inorganic adsorbents to prevent the adverse effects of mycotoxins in vivo should be approached with caution, and should be confirmed in vivo, paying particular attention to the potential for nutrient interactions.
An experiment was conducted to evaluate the efficacy of Toxisorb to ameliorate the toxic effects of aflatoxin (AF) in broiler chick diets. Birds were allotted to one of six dietary treatments that included: 1) basal diet containing neither adsorbent nor mycotoxin; 2) basal diet supplemented with 0,25% Toxisorb; 3) basal diet supplemented with 0,50% Toxisorb; 4) basal diet supplemented with and 3 mg AF/kg diet; 5) basal diet supplemented with 0,25% Toxisorb and 3 mg AF/kg diet; 6) basal diet supplemented with 0,50% Toxisorb and 3 mg AF/kg diet. The study was conducted in the Laborató rio de Análises Micotoxicologicas (LAMIC) at the Universidade Federal de Santa Maria (UFSM).
The effects of dietary treatments on chick performance from day 1 to 42 are presented in Table 2. Chicks fed 0.25% Toxisorb and 0.5% Toxisorb consumed similar amounts of feed (4482 and 4538 respectively vs 4436 g), and were as efficient (1.85 and 1.85 respectively vs 1.88) as chicks fed control diets. Chicks fed 0.5% Toxisorb gained more weight (P<0.05)>
as chicks fed control diets. In contrast, chicks fed AF alone consumed 29% less feed (P<0.05;>Chicks fed AF alone had enlarged pale livers with rounded margins. These observations indicated that Toxisorb at these inclusion levels did not negatively affect dietary nutrients (such as vitamins and minerals). Results also indicate that both dietary concentrations of Toxisorb were effective in ameliorating the toxic effects of AF that may be present in poultry rations at levels up to 3 mg/kg feed. Conclusions
The addition of Toxisorb at a dietary level up to 0.50% did not negatively affect chick performance or cause any pathological changes, which indicate that Toxisorb did not negatively affect dietary nutrients. Based on the in vitro and in vivo results, it can be concluded that Toxisorb is effective in ameliorating the toxic effects of aflatoxin. Read More......
Friday, June 6, 2008
Nutritive Value of Fermented Solid Cassava-waste by Trichoderma AA1 Mutant on Broiler Chicken
The research was aimed to study solid cassava waste (SCW) fermentation by using Trichoderma AA1 mutant to the changes of nutrient content and in vivo digestibility. SCW substrate (aw medium 0.99) was inoculated by using Trichoderma AA1 mutant (107 spores/g dry SCW). Three days incubation of aerobic solid substrate fermentation (SSF) method was used. Fermented solid cassava waste (FSCW) was harvested, sun-dried and grinded. The nutrient content and digestibility of unfermented SCW (USCW) and FSCW were tested. In vivo nutrient digestibility was measured on 70-days-male broiler chickens, used total collection method and wet force feeding technique. Kinds of nutrient digestibility measured were apparent and true digestibility of dry matter (ADDM and TDDM), apparent and true digestibility of soluble protein (ADSP and TDSP), apparent and true digestibility of starch (ADS and TDS), apparent and true metabolizable energy (AME and TME). The result of the research showed that FSCW had higher nutrient content than USCW, except for its crude fiber and cellulose contents. Fermentation caused a quite high increase of protein. Crude fiber and cellulose content had a high decrease, while starch, ash and nitrogen free extract (NFE) content was not change. SCW fermentation could significantly increase apparent and true nutrient digestibilities and metabolizable energy. ADDM and TDDM (P<0.05); style="font-style: italic;">Keywords: Fermented solid cassava-waste, Trichoderma AA1 mutant, nutritive value, broiler chicken.
[1] Fakultas Pertanian, Universitas Veteran Bangun Nusantara, Jl. Lewtjen Sujono Humardani No. 1, Sukoharjo 57521. Tel. +62-0271-593156, fax. +62-0271-591065, e-mail: alimursyid_wm@yahoo.com.
2 Fakultas Peternakan, Universitas Gadjah Mada, Yogyakarta.
3 Fakultas Teknologi Pertanian, Universitas Gadjah Mada, Yogyakarta.
The study of solid cassava waste fermentation.......
The study of solid cassava waste fermentation by the use of Trichoderma AA1 mutant
Zaenal Bachruddin , dan Zuprizal3
The research is aimed to study the influence of initial aw of medium, inoculum concentration, initial pH, and the length of incubation time of solid cassava waste fermentation by the use of Trichoderma AA1 mutant on cellulase production. Fermentation used solid substrate fermentation method. The medium was inoculated by Trichoderma AA1 mutant and incubated for four days. The variables covered initial aw of medium, inoculum concentration, initial pH, and the length of incubation time. The cellulase activity of the culture was measured. The result of the research showed that the best condition of solid cassava waste fermentation by the use of Trichoderma AA1 mutant to produce cellulase were: initial aw of medium was 0,99, inoculum concentration was 107 spre/g, initial pH was 5, and the length of incubation time was 3 days.
Keywords: Solid cassava waste, Trichoderma AA1 mutant, solid substrate fermentation, cellulase.
Read More......
Wednesday, June 4, 2008
Mutation on Trichoderma sp. to Increase Cellulase Secretion
Mutation on Trichoderma sp. to Increase Cellulase Secretion
Ali-Mursyid W.M. 1, M. Nur Cahyanto 2, Sardjono 2, Zuprizal 3, dan Zaenal Bachruddin 3
1 Faculty of Agriculture, University of Veteran Bangun Nusantara, Sukoharjo, Indonesia.
2 Faculty of Agriculture Technology, University of Gadjah Mada, Yogyakarta, Indonesia.
3 Faculty of Animal Science, University of Gadjah Mada, Yogyakarta, Indonesia.
This research is aimed to increase cellulase secretion on Trichoderma sp. by mutation method. Trichoderma PK1J2 (5 x 108 spore/ml) was turned into a suspension in mutagen solution (400 μg/ml ethidium bromide dan 0,5 M ethyl methane sulfonate) for 120 minutes. The screening of mutants which were able to produce hyper cellulase secretion was done by spreading it on a solid medium containing 1% carboxy methyl cellulose as the single carbon source and 5% glycerol as the catabolite repressor. Mutants which were resistant to catabolite repression and produced hyper cellulase secretion would form larger clear zone than its parent strain after it was flooded by 1% congo red indicator. Mutant AA1, AA2, AB1, AB2, and AC1 were chosen in this screening. The cellulase activity of those five mutants was measured after it was inoculated in liquid medium for 4 days. Cellulase activity measurement was done by using number 1 Whatman filter paper substrate. From the five mutants, mutant AA1 gave highest cellulase activity. Then mutant AA1 and its parent strain were inoculated in liquid medium for 7 days and its cellulase activity was measured every day. The peak of cellulase activity was reached after being incubated for 5 and 7 days for mutant AA1 and its parent strain respectively. The maximum cellulase activity of mutant AA1 was 1.4 times higher than its parent strain. It is concluded that mutation on Trichoderma sp. produces mutant which is resistant to catabolite repression and is able to produce hyper cellulase secretion.
Keywords: Mutation, Trichoderma sp., cellulase, catabolite repression.
For full article (Indonesian language), contact us: wisnuhusodo@yahoo.com
Read More......
Tuesday, June 3, 2008
Sanitation (Cleaning and Disinfectants
Although the subject of sanitation procedures, as related to disease management, is frequently discussed, it is helpful to review basic principles and review facts for reducing microbe populations.
Diseases and infections have always been a major concern to the poultry industry--especially in the hatchery. Fortunately, microbial contamination can be prevented and controlled using proper management practices and modern sanitation products.
Microorganisms are everywhere! Some are relatively harmless while others are highly pathogenic. Some pose a lethal threat to one species of animal while remaining harmless to another species. Some organisms are easily destroyed while others are very difficult to eliminate. The moral is: Treat all microorganisms as if they are a severe threat to the health of the bird.
Understanding the terms used to describe microbial control is important when selecting the appropriate action for eliminating disease causing organisms. Three terms commonly used but often misunderstood are sterilization, disinfection, and sanitation.
Sterilization -->The destruction of all infective and reproductive forms of all microorganisms (bacteria, fungi, virus, etc.).
Disinfection -->The destruction of all vegetative forms of microorganisms. Spores are not destroyed.
Sanitation -->The reduction of pathogenic organism numbers to a level at which they no longer pose a disease threat to their host.
Most poultry producers have the impression that they are approaching a sterile condition because they use disinfectants, when they may only achieve a sanitized condition at the very best. The most important consideration to remember when striving for disease management is that "cleanliness is essential".
Proper cleaning removes the vast majority of all microbial organisms and is absolutely necessary before applying disinfectants. This applies to all areas of poultry production including hatchery, brooding facilities, poultry house, storage facilities or processing plants. The success of a sanitation program is limited only by its weakest link.
It is extremely important to remove as much organic matter as practicable from surfaces to be disinfected. All debris, manure, broken eggs, etc. must be removed from the facility. This is followed by thorough cleaning using warm water and appropriate cleaning aides. Focus attention on selecting the proper detergent and thus producing the cleanest environment possible. Pay special attention to compensating for variations in water hardness, salinity and pH. A thorough rinsing with abundant quantities of potable water completes the cleaning process and removes most lingering residues of detergents, organic matter or microbial organisms. Only after the facilities have been thoroughly cleaned, will the surfaces be suitable for treatment with an appropriate disinfectant solution.
Not all disinfectants are suited for every situation. When selecting the disinfectant, carefully consider:
The type of surface being treated.
The cleanliness of the surface.
The type of organisms being treated.
The durability of the equipment/surface material.
Time limitations on treatment duration.
Residual activity requirements.
If the surface is free of organic matter and residual activity is not necessary, quaternary ammonium and halogen compounds may be used effectively. However, if surfaces are difficult to clean, residual activity is required, or the contaminating organisms are difficult to destroy, then multiple phenolics or coal tar distillates may be necessary.
Careful attention can assure that the disinfectant (if used as directed) meets requirements of the user. Be reasonable and don't expect the product to produce unattainable performance. Instead, select the proper product and/or modify disease control practices.
In general, disinfectants can be divided into seven major categories. The various classes of disinfectants are:
• Alcohols
• Halogens
• Quaternary Ammonium Compounds
• Phenolics
• Coal Tar Distillates
• Aldehydes
• Oxidizing Agents
Although many disinfectants are available, those most suited for hatcheries include quaternary ammonium compounds, phenolics and aldehydes are more suitable for use in poultry houses, and halogens are very effective if used in watering systems and on non-metallic equipment. Each disinfectant is best used only in appropriate locations, to meet the purposes for which it is designed.
Several considerations must be remembered when using any disinfectant to maximize its effectiveness. Some of these general considerations are:
Few disinfectants are effective instantaneously. Each requires a certain amount of time to bond with the microbe and exert a destructive influence. Allow adequate contact time (usually 30 minutes is sufficient) or select a different disinfectant.
When selecting disinfectants, consider their effectiveness on organisms that are of greatest concern. If a hatchery is experiencing problems with a certain viral disease, the disinfectant selected must be effective for destroying the specific organism causing the problem. Not all disinfectants are effective on all types or species of organisms.
In most situations it is advisable to clean and disinfect in different operations that are separated with thorough water rinsing. Many cleaning/ disinfecting producers promote their product based on ease and economy of use because they clean and disinfect in one operation. If these products are used, make sure that they satisfy all efficacy requirements demanded of other disinfectants.
The efficacy of disinfectant solutions is usually enhanced when applied in warm solutions rather that cold solutions. "Hot" solutions, however, may reduce disinfectant efficacy or promote a "cooked-on" condition for unremoved protein-rich residues.
When possible, allow all surfaces to dry thoroughly prior to reuse. Dryness helps prevent the reproduction, spread and transport of disease organisms. Although a surface is clean, it is more easily recontaminated with organisms if water remains on the surface.
It is important when selecting the best disinfectant to consider its effect upon the developing embryo and the hatchery environment. Embryos are in a very sensitive stage of development when the eggs enter the hatchery. They can be severely affected if subjected to chemical vapors, even if a sterile environment is provided.
It must be remembered that an egg is not produced in a sterile environment. Before it is laid, the egg is subjected to a series of microbial attacks that can reduce the embryo's potential to develop into a healthy, robust chick. The vent is probably the most contaminated area that an egg passes through. Poorly maintained nests can also distribute organisms to noninfected eggs. Fortunately, nature has provided several protective barriers for the embryo. Hatchery personnel must not conduct any procedure that interferes with the egg's natural defense. Producers must make every effort to collect and store eggs so that natural protections are not compromised.
Keeping egg shell surfaces dry is very important to prevent excessive microbial contamination and shell penetration. Without benefit of aqueous water the potentially dangerous microorganisms have little opportunity to invade the egg shell and infect the embryo. Sweating of eggs as they are moved from warm to cool environments must be prevented if sanitation programs are to be successful.
Embryos have the same requirements prior to pipping that the chicks have following hatching. They have the need for heat, moisture, and a high-quality source of air. They can be severely affected by harmful fumes originating from many chemicals often found in or near the hatchery. Although hatchability may not be affected, the quality of the chicks can be reduced. Whenever unusual odors are detected in the hatchery to come from detrimental chemicals, the product must be removed. This applies to all chemicals within the hatchery, including disinfectants. As an example, vapors produced by improper use of phenolic disinfectants can cause changes in egg proteins and impair hatchability and chick quality.
Improper selection or use of some disinfectants can damage or hinder the function of hatchery equipment. Many disinfectants are corrosive and damaging to equipment parts. Some disinfectants can clog and gum-up spray nozzles if added to the water used in humidifiers. It is possible that electronic control devices can also be severely damaged or destroyed after prolonged exposure to some disinfectants.
Select disinfectants wisely and always follow label directions for their safe use. Not only does management have the responsibility to maximize hatchability and chick quality, but also to provide a safe working environment for the hatchery personnel. Safety of the people working in the hatchery must never be sacrificed for cost or productive efficiency.
Assuming that a proper state of sanitation is achieved, it must be remembered that the status of disease-free surfaces can be compromised if facilities are not maintained properly. Hatchery personnel must be made aware that they can be a major source of reinfection by transporting of microorganisms on clothes, hands and attire. Since people are direct carriers of microbes, provisions must be made available at appropriate locations in the hatchery for the washing of hands and footwear. Laboratory coats and caps can significantly reduce the spread of microbial organisms. Restricting movement of hatchery personnel by assigning duties within specific areas can reduce the distribution of organisms throughout the hatchery.
The risk posed by disease causing organisms is a constant challenge to hatchery personnel. Always use control measures that have been proved effective rather than trusting visual cleanliness as an indicator of sanitation. A clean surface does not always indicate a disease-free state. Assuming so may be fatal to the chicks and the management program.
Friday, May 30, 2008
Prevention of Poultry Disease
An adequate disease prevention program is essential to a profitable commercial poultry operation. Chronic diseases can reduce efficiency and increase costs. Although a disease prevention program may not show immediate returns on the investment, it will be profitable in the long term.
Sources of disease
Humans, whether as visitors, neighbors or farm workers, can be a major source of disease transmission. Carriers can include employees who work on several poultry farms and equipment that moves between farms.
Poultry brought to the farm can carry infectious diseases. Day-old chicks or poults, pet birds, replacement pullets, cull- or sickpen birds, or birds of different ages or species are all possible sources of contamination. Wild birds may carry and transmit diseases to commercial poultry flocks. Certain diseases, such as salmonella and coliforms, may be transmitted from the dam to the offspring through the egg.
Poor sanitation also can cause disease problems. Once a site is contaminated, carryover from previously infected flocks may become a reoccurring problem.
Disease outbreaks are influenced by the general condition of the flock. Conditions caused by poor management can reduce the flock's resistance to infection.
Disease prevention
Proper security measures can greatly reduce the chance of disease outbreaks. Use disinfectant foot baths or wear plastic foot-coverings when entering buildings. Change foot baths often to keep them effective. If you use equipment for more than one flock, wash and disinfect it before introducing another flock or using it in another building.
Only bring in poultry from disease-free flocks. Secure your facilities from wild birds. Don't keep pet birds on the premises, and avoid contact with other flocks.
Practice "all in, all out" with flocks whenever possible. Thorough cleaning and disinfecting between flocks will help reduce outbreaks. Include a period of down time (two weeks minimum) in your flock schedule. Removal of built-up litter may be necessary if a disease outbreak has occurred.
To prevent spread of disease, control rodents and insects, keep buildings clean and dispose of dead birds. Clean and disinfect the facilities in the following manner:
• Remove all birds from the building. Clean out the old feed and remove all movable equipment.
• Hose the ceilings and walls before removing litter. Dispose of litter as far from the house as possible.
• Clean equipment and all items to be reused and repair building if needed.
• Wash the house thoroughly with a high-pressure wash to remove all manure deposits.
• Disinfect with a water-soluble compound such as quaternary ammonia, phenol compound, iodophor, coal-tar or a chlorine disinfectant.
• Apply an insecticide approved for poultry use.
• Replace the litter and return equipment.
• Lock the building and let it stand empty for two to four weeks.
Maintain proper management techniques that do not stress the birds. Good ventilation, dry litter and proper temperatures will provide conditions conducive to good health.
Follow an approved vaccination program.
References
• Schwartz, L.D., 1977. Poultry Health Handbook, College of Agriculture, Pennsylvania State University.
• Hofstad, M.S., 1984. Diseases of Poultry, Iowa State University Press.
by : Jeffre D. Firman
Department of Animal Sciences
Link
