Antibiotik adalah zat khemis khusus yang dihasilkan oleh mikroorganisme seperti ragi, jamus dan bakteri. Istilah antibiotik berarti pertentangan dengan hidup atau merusak kehidupan. Suatu antibiotik adalah stu zat yang dibuat oleh organisme hidup yang menghalang-halangi atau merusak kehidupan organisme lainnya.
Antibiotik digunakan untuk melawan infeksi dengan cara pencegahan atau pengobatan. Antibiotik diberikan sejumlah 2 sampai 10 gram per ton ransum, merangsang pertumbuhan anak ayam yang dipelihara dalam lingkungan yang tidak bebas hama. Karena zat tersebut merangsang pertumbuhan dan memperbaiki produksi telur dalam keadaan stress, maka zat tersebut membantu dalam pengambilan makanan yang efisien. Antibiotik harus digunakan sesuai dengan petunjuk pabrik yang memproduksinya.
Dari penelitian ternyata aureomisin (khlortetrasiklin), basitrasin, zinc basitrasin, oleandomisin dan virginiamisin dicampurkan dalam ransum berguna sekali untuk merangsang pertumbuhan anak-anak hewan. Jumlah ransum yang dapat dihabiskan dakan sehari akan bertambah dengan penggunaan antibiotik tersebut dan jumlah ransum yang diperlukan untuk kenaikan berat tiap kilogramnya akan berkurang.
Scientists in Germany are reporting development of test that can answer one of the most frustrating questions in the animal kingdom: "Is that bird a boy or a girl".
Their study, a potential boon to poultry farmers and bird breeders, is scheduled for the Feb. 15 issue of ACS´ Analytical Chemistry, a semi-monthly journal.
Juergen Popp and colleagues point out that the boy-girl question can be difficult to answer in birds that lack distinctive, gender-related plumage.
Since birds lack external genital organs, sexing a bird typically involves endoscopic examination of the animal´s gonads under general anesthesia or specific molecular biological methods. Since these methods are expensive, time-consuming, and stressful for the bird, scientists long have sought a quick, minimal-invasive sexing alternative.
In the new study, researchers describe such a test, which involves analysis of tissue pulp from birds´ feathers using a highly sensitive lab instrument. The method, called ultraviolet-resonance Raman (UVRR) spectroscopy, took less than a minute, and identified the birds´ sex with 95 percent accuracy, the scientists say.
The different DNA content in male and female chicken allows for gender differentiation via its characteristic Raman fingerprint.
Government study shows Salmonella levels over five times higher in intensive egg production than organic.
The Soil Association can reveal that a recent government survey  shows that organic laying hen farms have a significantly lower level of Salmonella. Salmonella is a bacterium that causes one of the commonest forms of food poisoning worldwide. 
The study showed that 23.4 per cent of farms with caged hens tested positive for salmonella compared to 4.4 per cent in organic flocks and 6.5 per cent in free-range flocks.
The research also showed that the highest prevalence of salmonella occurred in the largest holding size category (30,000 birds or more). This was over four times the average level of salmonella found in flocks closer to the maximum size allowed under Soil Association organic standards. 
These results support Hugh Fearnley-Whittingstall and his ‘Chicken Out’ campaign to improve the welfare standards of chicken production.  It also adds weight to the argument that although ‘free-range´ production would certainly be a positive step forward, it is still some way behind the Soil Association’s organic poultry systems , which ensure truly free range birds and offer the highest standards of animal welfare as acknowledged by respected animal welfare groups such as Compassion in World Farming.
Emma Hockridge, Soil Association policy department said: “Anyone watching Hugh and Jamie reveal the appalling conditions millions of chickens endure in the cramped, windowless sheds of factory farms will be in no doubt that organic and free-range chickens have a better life.
"This research confirms the Soil Association´s view that there are serious potential human health implications from such intensive systems. Whilst Salmonella food poisoning can be avoided through proper cooking of eggs and meat, anything that reduces the incidence of this bug should be encouraged – like genuine free-range, organic farming.”
 Survey of the prevalence of Salmonella species on commercial laying farms in the United Kingdom Published in The Veterinary Record (2007) 161; 471-476
 Around 15,000 cases of Salmonella are reported to the UK´s Health Protection Agency (HPA) each year. http://188.8.131.52/hpa/news/articles/press_releases/2004/041005_salmonella.htm
 Intensively farmed chickens reared for meat can be housed in flocks 30 – 40,000 strong. Even the RSPCA´s Freedom Food standards allow 16,000 egg-laying birds per house, and there is no limit on flock size for free-range meat birds.
In contrast, Soil Association organic standards recommend flock sizes of 500 – with absolute maximum flock sizes of 1,000 for meat birds and 2,000 for egg birds allowed only with special permission and additional management measures in place.
 Hugh Fearnley-Whittingstall’s Chicken Out campaign: http://www.chickenout.tv
 Some battery egg operations have as many as half a million birds. Most battery cages house four or five birds, each with about as much room as an A4 sheet of paper. All animals on Soil Association organic farms must have access to outdoor ranges and pasture, with an emphasis on enabling the animals to express their natural behaviour. Unlike intensively reared birds, organic chickens can’t be given routine doses of antibiotics which weaken the animal´s natural immune system so increasing reliance on drugs, as well as being linked to creating antibiotic resistant ‘superbugs´ with serious human health implications.
There are now approximately 29 million egg-layers in the UK over 70 per cent of which are housed in battery cages. Today three-quarters of the UK´s eggs come from fewer than 300 units, each with 20,000 or more layers.
Batteries not included – executive summary:http://www.soilassociation.org/web/sa/saweb.nsf/d39dda83e1f3c019802570ad005b4516/c34bd66834fb014380256df60043d53f!OpenDocument
Source: The Soil Association
IN preliminary trials, NOAA Sea Grant researchers have for the first time demonstrated the feasibility of using a live-attenuated vaccine to prevent the deadly Streptococcus iniae infection in fish.
The success raises the possibility of being able to inoculate hybrid striped bass, tilapia, rainbow trout and other cultured species orally through feed, instead of having to inject individual fish – a prohibitively labour-intensive process for American farms.
Besides the economic benefits, live-attenuated vaccines also stimulate a more robust immune response than vaccines from killed pathogens, thus offering better protection from infection, said John Buchanan, a former researcher at the University of California at San Diego.
There are currently two vaccines on the market for preventing S. iniae infections – AquaVac Garvetil and Norvax Strep Si. Both are classical vaccines based on exposing fish to killed versions of bacterial pathogens. However, neither is approved for use in the United States, Buchanan said. In addition, AquaVac is for use in tilapia only, and Norvax is most effective when fish are immersed in a 60-second dip initially; subsequent booster doses can be delivered orally.
The vaccine that Buchanan and UC San Diego pediatrics professor Victor Nizet are testing, in collaboration with Kent SeaTech, is based on mutating genes of the bacterial pathogen – not on killing the pathogen outright. These mutants have weakened virulence, but they can still infect fish, eliciting a strong adaptive immune response, in which antibodies to the real pathogen are created.
In the trials so far, their vaccine has been administered through injection, which means that each fish has to be given a shot. However, as Jim Carlberg, president of Kent SeaTech, emphasised: “The beauty of live-attenuated vaccines is that you have the potential to put the vaccine in feed.” The key is to be able to mutate a gene that does not wipe out the weakened pathogen´s ability to orally infect the animal.
“A vaccine that can be put in feed would have a huge potential advantage in cost,” Carlberg said.
“Oral delivery is the gold standard for aquaculture,” agreed Jeff Locke, a doctoral student with Nizet, who used to work at Kent SeaTech, a large hybrid striped bass farm in Southern California.
S. iniae is a ubiquitous disease and a fairly chronic problem,” Carlberg said. “It has a huge economic impact on worldwide aquaculture.”
About 26 species of fish are susceptible to S. iniae, which causes meningitis.
Source: Fishfarmer Magazine
Steve Leeson, Ph.D., from the University of Guelph, recently revealed new findings on the importance of chick nutritional strategies.
Leeson was sponsored by Alltech, a global leader in animal health, to present his findings at the International Poultry Expo, held in Atlanta, Georgia. His findings exhibited the importance and impact of a comprehensive nutritional strategy for chicks during the first seven days out of the egg, which would in turn yield heavier birds at 42 days.
Leeson reported that a prestarter diet pack encompassing several patented Alltech technologies fed for just the first seven days outside of their shell yielded results such as:
* 34 percent heavier birds at 4 days
* 21 percent heavier birds at 7 days
* 17 percent heavier birds at 21 days
* 12 percent heavier birds at 33 days
* 9 percent heavier birds at 42 days
"Alltech has always been committed to providing natural solutions to the feed and food industries, and this new research supports our product, ‘The 7-Day Charge,´" said Dr. Pearse Lyons, president and founder of Alltech. "Just as all babies – human and animal alike – need strong nutritional foundations for future development, Dr. Leeson has proven that this is true for chicks as well."
Attendees were amazed to hear about the possibility of a bird weighing 200 grams more after 42 days because of a mere seven-day nutritional strategy at the beginning of a bird´s life.
Since 1980, Alltech has provided natural nutritional solutions to the feed and food industries. Alltech´s presence has grown with offices and distributors in 113 countries and more than 1,800 employees around the world.
Source: Alltech Inc.
Results from a recently completed Poultry CRC proof-of-concept project, Using "machine vision" to count hens and reduce egg breakage, has demonstrated that ‘machine vision´, or video image analysis (VIA – the ability of a computer to ‘see´), can be used to monitor egg belts for potential blockages and has the potential for effectively counting hens.
Testing under commercial conditions has demonstrated that the ability of a machine to automatically scan the egg belt to identify foreign (non-egg) objects has improved to a 95% success rate.
The Project Leader, Greg Cronin, from DPI Victoria´s Animal Welfare Science Centre (AWSC), says that the results indicate that VIA can be successfully used to monitor activities within the modern cage-layer shed.
“Continued refinement of the software and hardware will further improve the detection rate,” said Greg, “with potential benefits measured not just in terms of economics, but in more varied and interesting jobs for stockpeople, which may also result in better retention of staff.”
As Australia´s population, and its workforce, ages, the pool of personnel available to the poultry industries is expected to shrink, and this technology may be part of a solution to the problem.
“VIA technology could also be applied to automatically monitor other production processes in the poultry and other livestock industries,” said Greg, “providing benefits from improved frequency of surveillance and enabling more time to be made available to the stockperson for less-mundane tasks. We consider counting hens in cages a first step in being able to monitor hens automatically, potentially leading to a mechanism for automatic monitoring of hen welfare and health.”
While VIA has already been used to grade eggs after collection, the use of VIA to reduce the incidence of cracked or broken eggs prior to collection does not appear to have been considered before this project.
Source: Australian Poultry CRC release