Tag Archives: Health

Chicken therapy

Resident Sally Cross-Sevon was introduced to "Clementine."

Resident Sally Cross-Sevon was introduced to “Clementine.”

Ellen Levinson’s tone becomes nostalgic as she recalls how she felt the day last summer when Terry Golson placed a hen in her lap.

“Having that chicken in my arms and holding it against my body was profoundly soothing,” Levinson said.

But even in that moment, she wasn’t thinking so much about herself as her clientele. Levinson is executive director of Life Care Center of Nashoba Valley , a nursing home in Littleton that offers residential care for elderly patients with memory loss as well as short-term rehabilitation services.

“We deal with agitation a lot on the dementia unit,” Levinson said. “The chicken felt wonderful to hold. Something clicked. If I were agitated or upset, this is what I would want.”

She couldn’t have been in a better place when the idea struck her. She was attending a seminar led by Golson, a Carlisle resident whose acclaim as a poultry-raising authority has landed her on Martha Stewart’s TV show and in the New Yorker magazine.

During the backyard workshop, which Golson offers periodically, Levinson found herself thinking more about how the presence of chickens might affect her patients.

“We spent some time watching the chickens as they pecked in the ground and took dirt baths, and it was fascinating,’’ Levinson said.

“One of the issues present in people with dementia is short attention span. They can’t sit still for even half an hour. But if we had the chickens nearby, I started thinking, our residents would be able to watch them for a short time, move on to something else, then come back and watch them some more. It seemed like a natural fit.”

The notion wasn’t quite as far-fetched as it might seem. With its grass-rich campus amid what was once agricultural land in Littleton, the Life Care Center has already introduced several nonhuman inhabitants into the mix. Permanently installed on the 40-acre property are goats, llamas, an alpaca, and an indoor cat, and dogs come in for daily visits; Levinson wondered how her patients might react to chickens in their midst.

Levinson asked Golson to visit the facility and advise the Life Care staff on the viability of installing a chicken coop on the grounds. Golson loved the idea. After discussing with Levinson what would be required to set up a flock, Colson and the director of the facility’s memory support unit, Erica Labb, arranged a series of visits to introduce the residents to the idea.

It was during these interactive sessions that Labb, who describes herself as “not that much of an animal person previously, but now I’m becoming one,” was struck by something she doesn’t typically see during group events in her unit: rapt attention.

Unlike the more common animal-therapy programs in which dogs are trained to visit hospitals and nursing homes, the chickens are not expected to interact in any particular way with patients. And unlike the llamas, goats, and alpaca, which are kept on the Life Care Center’s front lawn, the chickens and their coop are right outside the large picture window in the activity room.

It became clear to Golson in her initial presentations that chickens carried strong associations for some of the residents. Many of them, now in their 80s and 90s, grew up around farms or had other memories associated with farm animals.

Resident Thelma Mollot, age 101, was introduced to "Beulah," by "Chicken Captain" Terry Golson (right).

Resident Thelma Mollot, age 101, was introduced to “Beulah,” by “Chicken Captain” Terry Golson (right).

“Chickens are innately engaging,” Golson said. “I made it tactile by passing around feathers and eggs. For some of these elderly people, it’s been years since they’ve touched an egg. For those who used to do a lot of cooking or baking, having an egg in their hand can be very evocative. For one woman who grew up in Italy, holding the egg tapped into memories of making homemade pasta.”

One of Golson’s areas of expertise is, for lack of a better term, chicken personality. It was important to her to find the right mix of fowl temperaments to make this experiment work. So she began the way she always does with newcomers: by getting to know them.

“Last winter, I ordered 26 chicks from a mail-order hatchery. Once they arrived in March, I observed their innate personalities and eventually chose the five that seemed the friendliest.”

Not only did Golson want the right social characteristics among the Life Care flock, she also wanted the nursing home residents to be able to distinguish among them visually, so she chose a variety of breeds and colors to make the final cut.

The chickens and their coop showed up at the nursing home late last month.

Labb came up with an inspiration for naming the birds; she chose from among a list of the names of the residents’ mothers and grandmothers. As a result, the tenants of Life Care’s new chicken coop are Clementine, Elsie, Beulah, Mae Belle, and Millie.

“My hope is the residents get to know the chickens individually and develop some interest in their social life,” Labb said. “They’ll develop favorites. Eventually, I hope they will participate in caretaking, feeding, gathering eggs. The goal really comes down to engagement.”

Labb never anticipated adding “chicken captain” to her resume, but a few lessons from Golson taught her what she needed to know about keeping the birds safe and healthy. The maintenance staff bears the brunt of the feeding and cleaning for all the farm animals at Life Care. At this point, having animals on the property is second nature to them. Not so for those farther afield; Levinson received a phone call from a representative of the center’s accounting firm in Tennessee, who wanted to know why the nursing home had just received a bill for a chicken coop.

Littleton resident Richard Carozza , a recent McGill University graduate who is applying to medical schools, has joined the Life Care team for the summer as a volunteer to apply his scientific research skills to the experiment.

“We’ve already discovered that Life Care has a lower usage of antipsychotic drugs than other facilities with dementia patients,” he said. “Could this be related to the presence of animals?”

And by extension, Carozza wonders, can he prove a measurable difference in the patients’ behaviors after they start interacting with the chickens? He will spend much of the summer investigating these questions.

So far, Labb and Levinson both say they are pleased with the residents’ interest in the coop, and eager to foster continuing interaction throughout the summer, including having the residents help gather eggs once the chickens start laying.

Golson would like to see this model extended to other long-term care and memory loss facilities, particularly if the same careful attention to detail is followed.

“Life Care went far beyond just throwing some chickens and a coop out onto the lawn,” the facility’s consultant said. “It’s important that this not be done in a slapdash way. It has to come across as a beautiful, well-cared-for flock, just as this one is.”

And the presence of the animals helps when the residents have visitors as well.

“It’s a way of connecting generations,” Labb said. “Nursing homes can be scary places for young children. People sometimes don’t know how to visit. The animals provide something for everyone to watch together.”

Golson, whose website (www.hencam.com) features live streaming video from her own chicken coop, believes that “watching chickens is both engaging and peaceful at the same time.”

“Having chickens in the backyard is like looking at the ocean. There’s a lot of movement and at the same time it feels calming. What could be better for memory-loss patients than this constant ebb and flow in which they can engage? It’s a perfect match.”

Source: http://www.bostonglobe.com/metro/regionals/west/2013/06/26/flock-chickens-provides-new-form-animal-therapy-for-memory-loss-patients-littleton-nursing-home/Oj9mrJmiCmAI74ryCe4JuK/story.html


The case against antibiotics in poultry

More than 50 billion birds a year are produced in industrial poultry hatcheries worldwide.

On January 4th, 2012 the FDA quietly prohibited the “extralabel” or unapproved use of the common (yet strong) cephalosporin class of antibiotics in cattle, pigs, chickens and turkeys to be effective April 5, 2012. The FDA says it is taking this action to preserve the effectiveness of cephalosporin drugs for treating disease in humans, for it has been noted that as cephalosporin use increases in animal agriculture, human effectiveness diminishes.Cephalosporin antibiotics are a stronger cousin to penicillins. Doctors currently use cephalosporins to treat pneumonia, strep throat, tonsillitis, bronchitis, urinary tract infections and to prevent bacterial infection before, during, and after surgery.

Currently, unapproved use and abuse of antibiotics for food-intended animals is common practice. Sources say, some 80 percent of all antibiotics sold in the U.S. are being fed or injected into cattle, pigs and poultry on industrial factory farms.2

One such unstudied and unapproved use of cephalosporins in food-intended animals, is their injection into poultry eggs. Although the FDA has approved the use of cephalosporins on animal farms for various specific veterinary purposes, such as curing an existing infection, the unapproved or “extra-label” use of cephalosporins, to suppress potential future infection, by injecting doses into chicken eggs just before the eggs hatch, has become widespread.

Every five weeks, a large poultry farm sees a delivery of newly hatched chicks (which have been mechanically injected with a third generation cephalosporin just prior to hatching). The chicks are then rapidly fattened with a feed laced with low-dose antibiotics, most likely amoxycillin and tetracycline, which are currently allowed in animal feed and will continue to be allowed in feed by the FDA.3 When the chicks reach three and a half pounds they are sent off for slaughter. Years ago, it took two months to fatten up a chicken, today they can eat their way to 3.5 pounds in just 33 days. Today’s low dose antibiotics are the reason the birds are bulking up so quickly. Upon exit of the chickens, the floor of the once crowded pen is cleaned for the first time in over five weeks, the month plus of excrement that the birds have been sleeping and sitting in from day two of their lives, is scraped away, and the process repeats itself. These are the types of conditions that set in motion the use of preventative antibiotics.

The FDA has taken a bold and much needed first step to reign in antibiotic use. FDA officials, scientists and physicians have been warning for years that antibiotics in agriculture pose a “serious public health threat” and action needs to be taken on the issue, but no concrete steps to limit the drugs had been taken until the January 4th announcement.

Another way to decrease antibiotic use on factory farms is to reduce demand. There appear to be three options: become a vegetarian, buy from a local, sustainable, humane farmer, or, for those who are capable, start your own small scale hatchery or poultry farm! The number of people dependent on big industry would decrease, and many a chicken and turkey would lead a more dignified life.

While we’ve all heard that over-prescription of antibiotics to people is one cause of resistance, another major cause is due to the unrestricted use of antibiotics on factory farms. And not just when animals are sick: healthy animals are fed antibiotics every day because it makes them grow bigger, faster. Marketplace tests 100 samples of chicken for antibiotic resistant strains of sakmonella. www.cbc.ca

The U.S. animal farming industry consumes over 30 million pounds of antibiotics per year.

Antibiotic use on U.S. livestock in 2010:  Cephalosporins- 54,207 pounds (24,588 kilograms),  Penicillins- 1.9 million pounds (870,948 kg),  Tetracyclines- 12.3 million pounds (5.6 million kg). www.mnn.com

The use of penicillin and tetracyclines – the fattening drugs the F.D.A. has chosen not to regulate – increased 43 percent and 21 percent from 2009 to 2010. In anticipation of the new law, the use of cephalosporins dropped 41 percent from 2009 to 2010.3

*1)  www.miller-mccune.com

*2)  newsfeedresearcher.com

*3)  bittman.blogs.nytimes.com


Leverstein-van Hall, MA et al. Dutch patients, retail chicken meat and poultry share the same ESBL genes, plasmids and strains. Clinical Microbiology and Infection, 2011.

Pappas, G. An Animal Farm Called ESBL: Antimicrobial resistance as a zoonosis. Clinical Microbiology and Infection, 2011.

Further Reading:

About cephalosporins: www.emedexpert.com

FDA Press Release: www.fda.gov


In Germany, although non-therapeutic use of antibiotics has been banned – conditions are poor: www.spiegel.de

Source: http://www.inspirationgreen.com/antibiotic-chicks.html

Lesson 777 – Gaining Ground by Forrest Pritchard – interview

This is a great blog by Wendy Thomas about the ethical chicken farmer Forrest Pritchard and his new book Gaining Ground.

Lessons Learned from the Flock

gaining groundHey folks, there’s a new farming/organic living book out that is generating a lot of buzz. Written by Forrest Pritchard (and with a foreword by Joel Salatin) Gaining Ground is the true story of how a young man chose to take on the task of literally saving the family farm by turning it into an ethical and profitable way to make a living.

It’s a great story filled with ups and downs, humor and life lessons. In short, it’s the kind of book that makes you feel good after reading it. That’s the kind of story that I love most to read.

You can tell me about an adventure and I might read your book, but tell me how that adventure changed you and what you learned as a result and chances are, your book will make it to my reading list. Gaining Ground falls in the latter category, it…

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Poultry Diseases Up Close – Gape Worm or Syngamus Trachea

The Gape Worm also called Syngamus Trachea mainly affects chickens, turkeys and game birds, especially pheasants but can affect other wild birds as well which makes eradication difficult.

Infestation often occurs when there are wild pheasants close to your birds. Gapeworm infestation can occur either directly by birds eating eggs that have been swallowed or coughed up by infested birds, or indirectly by intermediate hosts such as earthworms or snails. Young birds up to 8 weeks of age are particularly susceptible to gape worm. Gapeworms normally live in the trachea (windpipe) but are also found in the bronchi and lungs.

Typically, eggs are picked up from the ground or intermediate hosts such as worms or snails. The eggs hatch and the larvae penetrate the intestine walls and move to the lungs and bronchi. It is here they go through a larval moult, before travelling up to the trachea. Male and female gapeworms attach to one another once they arrive here. This process takes around 7 days. Gapeworm lay eggs that get coughed up onto the ground or swallowed and passed out in the faeces.

Signs and Symptoms

Infestation causes respiratory distress. Gasping for breath or ‘gaping’ as it is known is the biggest sign of gapeworm. Shaking of the head and neck stretching are common. When birds are held, gurgling or a ‘tracheal rattle’ can often be heard. This can often be confused with respiratory infection, if in doubt, check for other signs of respiratory disease. If a heavy infestation occurs, death by suffocation will occur. Fully grown gapeworms are ‘Y’ shaped and vary in size between 1 and 2cm long.


Chickens are particularly prone to respiratory diseases so it is important to ensure you have a good worming schedule to eliminate the possibility of a respiratory problem being confused with a gapeworm infestation. Gurgling noises that come from the throat of the bird can be caused by gapeworm and can be confused with a respiratory problem.

As with all internal parasites, there are many treatments that will kill these worms but rotating the grazing area will help to stop birds becoming re-infected. Worming Chickens provides some ideas for worming poultry.Flubenvet is licenced for use in chickens and will kill gape worms.

Source: http://poultrykeeper.com/digestive-system-problems/gape-worm-or-syngamus-trachea

Residents of a Northampton care home help to raise baby chickens

editorial image

Residents of a Northampton care home in the UK helped to look after a baby chickens during the first few days of their lives.

Elderly people at Richmond Care Home in Grange Park took part in a 12-day living egg experience.

Claire Fry, senior village advisor, said: “The experience encourages social interaction, stimulates memories, reduces any stress levels and loneliness, is therapeutic and will bring joy to everyone looking after our little chicks.”

3 Dirty Chicken Facts Exposed

PHOTO: Many chickens sold in supermarkets are fed a steady diet of human drugs.Many chickens sold in supermarkets are fed a steady diet of human drugs.

Think the pink slime scandal is gross? There’s even more unappetizing news, this time from the poultry department. By testing feathers, researchers from Johns Hopkins University found that “healthy chicken” sold in your supermarket could have very well been raised on a steady diet of prescription, over-the-counter, and even banned drugs.

The full implication of people eating chicken containing these drugs isn’t even known, although previous studies have shown carcinogenic arsenic fed to chickens—something approved for use in nonorganic chicken farming—does wind up in the meat.

In the study, researchers tested feather meal, a by-product of chicken farming often used as fertilizer, because feathers accumulate important clues as to which drugs and chemicals chickens are exposed to during their short—usually about eight-week—lives.

The contaminated chicken report is the latest in a string of findings suggesting the industrial food system that supplies most supermarkets routinely engages in practices that could put consumers at risk.

And this, the study’s coauthor says, is just the tip of the iceberg.

“There are a wide spectrum of public health, social justice, and environmental concerns that stem from the way we raise animals for food,” explains researcher Keeve Nachman, PhD, assistant scientist and director of the Farming for the Future program at Johns Hopkins Center for a Livable Future, part of the university’s Bloomberg School of Public Health. “These concerns range from the generation and transport of bacteria that are resistant to antibiotics that are critical to human medicine, to the disproportionate concentration of animal-production sites and their associated air and water pollution in low-income communities of color, to the overwhelming energy and water inputs required to grow and transport feed for food animals.”

Dirty Chicken Facts Exposed

News of these dangers is going mainstream, too. In a recent New York Times column, Nicholas Kristof outlined the dangers of the industrial poultry system, saying, “I used to be skeptical of organic, but the more reporting I do on our food supply, the more I want my own family eating organic—just to be safe.”

Here’s what industry is feeding your chickens, according to feather testing:

Antidepressants, Painkillers, Allergy Meds

Sure, the conditions in factory farms are depressing. But researchers were surprised to find active ingredients of human antidepressant drugs like Prozac in the chicken feather product tested. The mood-stabilizing drug was detected in U.S.-sold chicken imported from China, and is apparently used to reduce anxiety in chickens, since stress can slow growth and lead to tougher meat, according to Kristof’s report.


Nachman’s team also detected caffeine in about half of the chicken feather samples. Caffeine is used to keep the chickens awake so they eat more and grow faster.

Banned Antibiotics

Surprise! Feather tests suggest large-scale poultry producers are using banned antibiotics in poultry production. “We were especially surprised to find residues of a number of over-the-counter drugs, including the active ingredients of Tylenol, Benadryl, and Prozac, but what was even more disturbing was finding residues of fluoroquinolone antibiotics, since these drugs have been banned from poultry production since 2005,” Nachman says.

This class of antibiotics includes Cipro, a high-powered drug often used in humans when other antibiotics don’t work. It was banned in the poultry industry about seven years ago because researchers were detecting that its use in farming was leading to antibiotic-resistant superbug strains that could potentially kill humans. To date, superbugs kill about 17,000 people in the U.S. a year.

Despite all this, the FDA has made it clear that it plans to not formally ban antibiotic use in food animal products, but rather ask farmers to voluntarily limit use.

“Our research suggests that drugs that are illegal in poultry production may still be in use,” Nachman says. “Given this, I have little confidence that a voluntary approach will have any impact on the food animal industry’s abuse of antibiotics.”

Seek Out Undrugged Meat

To find more humanely and naturally raised chicken, look for local grass-fed poultry farmers who don’t use routine antibiotics or arsenic in feed. (LocalHarvest.org is a good resource.) If you’re shopping in the supermarket, opt for organic—standards for organic include bans on the use of antibiotics, arsenic, and many other unappetizing chicken-farming practices.

Source: http://abcnews.go.com/Health/Wellness/dirty-chicken-facts-exposed/story?id=16724335&page=2#.UW_1D34tDS0

Poultry Diseases Up Close – Sour Crop

Sour crop and impacted crop, also known as crop binding, although relatively uncommon in chickens, is still something you need to watch out for in your flock. Unfortunately, there is a lot of misinformation on the web about how to deal with this condition; many of the home remedies and solutions are extremely dangerous, and often very cruel for the hens.

Typically, a hen’s crop will become impacted by something the chicken has ingested. The blockages could be the result of the hen ingesting tough grasses, sawdust, straw, hard grains or meat bones that get lodged in the crop.

Chickens may exhibit a large bulge in the crop area, diminishing weight, isolating themselves from the flock, hunching down or protecting their injury. The bird may also jerk their neck around trying to dislodge the blockage. Additionally, the stuck items in the crop may begin to rot, resulting in a sour smell coming from the chicken’s beak.

The Chicken Health Handbook explains that ‘Even if the bird continues to eat, nutrition cannot get through. The swollen crop may cut off the windpipe, suffocating the bird’.


To determine if your chicken may be suffering from sour or impacted crop, gently pick up the chicken and see if you can feel a hard or squiggly bulge in the chest; gently running your hands over the chicken’s breast area should be enough to feel if the crop is distended.

There may be a food bulge in the crop, particularly if the hen has just eaten – the crop is similar to a food storage pouch.  However, if the hen is exhibiting any of the other behaviors associated with this condition, such as head jerking or refusing to move, then a blockage in the crop is a distinct possibility.

Carefully open the chicken’s beak and have a sniff to see if there is a sour smell. Although the odor is difficult to describe and may vary depending on what the bird has ingested, it should be obvious that there is an unusual and unpleasant smell coming from the chicken’s beak.

If you suspect the chicken may have a blocked or impacted crop, it is best to isolate the chicken and only provide water or organic vegetable broth (we use kale and broccoli broth) to confirm that the hen is not able to pass faecal waste.

If you determine that the chicken does have an impacted or sour crop, there are several options on how to deal with it. The first option is to contact a qualified veterinarian for advice. Many of the farm vets will have experience with this condition and will be able to offer suggestions on how to deal with the problem.

Our largest, most healthy, hen recently had a combination of sour and impacted crop, and although we were able to help her pass the blockage, our veterinarian explained that often the chicken may have something else going on that causes the initial blockage problem such as tumors, sores or ulcers. The blockage may also be lower down in the hen’s innards and the only evidence you see is in the distended or engorged crop.

Impacted Crop

An impacted crop will generally feel much harder than a sour crop and a lubricant may be needed to help move the blockage. The application of small eyedroppers of organic vegetable oil (do not use petroleum-based oils) mixed with water into the chicken’s beak may be used to help lubricate the crop contents. However, it is vitally important to ensure the liquid is inserted well past the small hole at the base of the tongue that leads to the hen’s lungs.

Once the oil is added, the crop can be gently massaged in a downward motion to help further lubricate the crop and move the blockage through the hen. This may take several applications over the course of two days.

Keep the hen separated from the flock so you can monitor if she is passing any blockage. Provide her with access to water and/or vegetable broth. See the Recovery information below.

Sour Crop

If the crop feels very squishy and there is a foul smell coming from the chicken’s beak, the chicken can be assisted to help remove the sour liquid.

One option is to ‘vomit the chicken’. However, this is a dangerous procedure and should not be undertaken in a careless manner. If the ‘vomiting’ is done incorrectly it may result in the rotten fluid ending up in the chicken’s lungs which could lead to pneumonia. The procedure is best attempted with two people and under the guidance of a veterinarian.

Wrap the bird in a clean towel and gently tilt the bird forward (not backward) so that her body is vertical to the floor and the head is close to the ground while massaging the crop contents gently toward her mouth. You may need to open the beak to allow the vomit to flow out. The chicken should remain upside down for short durations only – 15 to 20 seconds maximum.

Repeat one to two times only. Allow the chicken time to rest and do not handle the bird roughly. When you think the hen has emptied her crop (partially or fully), be sure to keep the hen separate from the flock and give her time to rest. This may be repeated in two days time, though it is extremely important to not overdo this procedure.

Some veterinarians recommend assisting the chicken to pass the contents of the sour crop through the stomach and waste system as explained in the Impacted Crop section.


Surgery should not be conducted at home, and at no time should someone cut into, or expose the innards of, a fully conscious animal as this is a form of animal cruelty, and may, in some states or provinces, constitute animal abuse. There are numerous accounts on the web of backyard farmers cutting open a chicken’s chest and crop and removing the blockage. These accounts are not verified and it is important to consult with a qualified veterinarian before conducting ‘surgery’ on an animal.

If you cannot afford a veterinarian and are determined to perform the surgery at home, it is extremely important that you do not cut into a fully conscious animal as, aside from it being an act of cruelty, the animal’s ability to recover may be greatly diminished from trauma and/or shock. Ask your veterinarian for a sedative to ensure the animal does not experience pain during the procedure.

Use extremely sharp, sterile scalpels, wash your hands and the area where you intend to cut thoroughly with alcohol (not the kind you drink) and ensure that you know where you should be cutting. Carefully clean and close the wound after the procedure and isolate the hen until the wound heals.

Alternative treatment options: Add a drop of Rescue Remedy to the chicken’s water with a pulverized homeopathic Traumeel tablet and/or the remedy Arnica – these supplements will aid the hen in her recovery.


When your hen is recovering, provide her with a clean, quiet and safe environment where she can remain until she recovers. Provide clean, filtered drinking water and/or an organic vegetable broth with the addition of a few drops of organic oil such as olive oil or vegetable oil which will lubricate the inside of the chicken and help her continue to pass any blockages. Ignore all suggestion to use petroleum based oils or kerosene with chickens.

If the hen is droopy, consider inserting small eyedroppers full of blueberry water (mush up blueberries and extract the liquid) with the addition of molasses, honey or brown sugar. You can also add the homeopathic and flower remedies suggested above.

Withhold food for one to two days until you are sure she is able to pass waste again. Once she is passing waste again, slowly reintroduce soft foods – options include soft corn, finely grated apple or lettuce, plain yogurt, overcooked and finely chopped vegetables including chopped broccoli, kale and chard, or favourite fruits like mushy ripe watermelon and honeydew.

Choose food options that you know the hen will enjoy, but that will not lodge in her crop again. Monitor the chicken to ensure she is passing the food properly again and it is not building up in her crop again. Do not allow free access to large quantities of feed until you are sure she is out of danger and the blockage has passed. When the hen is back to normal, always ensure that she has access to oyster shell or grit.

Consider adding small amounts of lactobacillus or acidophilus to the hen’s food to ensure the repopulation of healthy bacteria in her stomach and aid in healthy digestion.

The chicken may need antibiotics if an infection develops from the blocked crop and/or surgery complications. Speak to your veterinarian.

Alternative treatment options: Add a drop of Rescue Remedy to the hen’s water or food along with a ground up homeopathic Traumeel tablet – both these supplements will aid the hen in her recovery.

Preventative Measures

Do not feed hard treats, grains or table scraps that can lodge in their throats or crops. Chickens should not be fed bones or large chunks of meat that they are unable to break up. Always ensure your flock has constant access to grit and oyster shells.

Source: http://www.greenmuze.com/blogs/green-muzings/2208-chicken-impacted-crop-or-sour-crop.html