COCCI People - Giant Leaps

Joyce Johnson forged new frontiers in coccidiosis control

Joyce Johnson with a group of poultry technical specialists from Latin America and Asia during a training seminar in 1979.

Remember America in 1969?

Joe Namath and the upstart New York Jets shocked the football establishment by guaranteeing a victory in Super Bowl III, Midnight Cowboy captured the Oscar for Best Picture, the Fifth Dimension took home a Grammy for Aquarius/Let the Sunshine In and the so-called Miracle Mets won baseball's World Series.

In the same year, astronaut Neil Armstrong stepped boldly on the moon while proclaiming "one small step for man, one giant leap for mankind." That event changed the world forever.

1969 was also a newsworthy year in the universe of poultry parasitology. The University of Georgia (UGA) Department of Poultry Science hosted the first-of-its-kind international Coccidiosis Symposium. A UGA research technician named Joyce Keener Johnson introduced a little program she developed for measuring gross intestinal lesions in chickens infected with this major protozoan disease.

While her protocol was enthusiastically received by the 150-some industry professionals who attended the conference, Johnson never dreamed her lesion scoring system would change the world of coccidiosis management forever.

Landmark System

This landmark lesion scoring scheme, complete with colored slides, came to be known not only as the Johnson-Reid Lesion Score System, named for the inventor and her mentor, W. Malcolm Reid, but also as an indispensable benchmark for all scientists working with cocccidia throughout the world. Lesion scoring had long been a commonly accepted criterion for determining the pathogenicity of coccidial species. However, no previous attempts had been made to standardize and describe the scoring scale to evaluate the severity of infection until Joyce Johnson tackled this challenging mission at Reid's suggestion.

"The biggest benefit of the Johnson- Reid Lesion Score System was that it provided an easily learned tool to measure the effects of anticoccidials and vaccines," says parasitologist Donal Conway, an Asbury, N.J.- based consultant in pharmaceutical product development.

"The system had a notable impact in the late 1960s and 1970s when ionophores were first being developed. It was still important in 2000 when the newest synthetic anticoccidial, diclazuril, was approved by the FDA," Conway asserts.

Coccidiosis lesion scoring according to the Johnson-Reid System is now the suggested methodology for all anticoccidial protocols submitted to the FDA for approval and for vaccine protocols submitted to the USDA.

"Even today, everyone who does a coccidiosis paper has to reference that Johnson and Reid work," says Dr. Greg Mathis, president of Southern Poultry Research, Inc. (SPR), based in Athens, Ga. The historic Johnson and Reid paper titled "Anticoccidial Drugs: Lesion Scoring Techniques in Battery and Floor-Pen Experiments with Chickens" was published in 1970 in Experimental Parasitology.

A Wealth of Experience

After Johnson completed her Masters degree under Reid's tutelage in 1963, she remained in the UGA Poultry Science Department for 33 years. As a Research Technician III, the Alcoa, Tenn., native worked for Reid for 18 years, then for Peter L. Long for 12 years, and finally for Larry McDougald. Reid's research focused on chemotherapy, Long's centered on immunology, while McDougald's is devoted to both chemotherapy and cellular immunology.

In 1994, Mathis hired Johnson to work for his firm, which conducts research for the poultry and pharmaceutical industries. Approximately onethird of SPR's clients, including Schering-Plough Animal Health, are involved with some aspect of coccidiosis research.

"What's amazing to me is that so many people having what they thought were new ideas for coccidiosis research would contact us, and Joyce would always tell them 'we've already done that'," Mathis adds. "Joyce was familiar with all the facets of coccidiosis and anyone who knew anything about coccidiosis knew Joyce."

According to Conway, Johnson continually challenged her colleagues to hone in on the key questions associated with evaluating coccidiosis, anticoccidials and vaccines:

"� How severe is the infection?

"� To what extent is the coccidial infection affecting feed consumption, feed conversion and weight gain?

"� Is the product working? If so, how effective is the anticoccidial program?

"� What is the cost to treat or vaccinate the flock?

Celebrating the Contributions of a Cherished Colleague

Tragically, Joyce Johnson was killed in an automobile accident on the morning of January 25 of this year, en route to her job at Southern Poultry Research, Inc. (SPR), Athens, Ga.

Everyone who knew Johnson had a great deal of respect for her, says UGA poultry scientist Larry McDougald.

"She was always the mainstay of the UGA Poultry Science laboratory, and made a tremendous positive impact on all of our graduate students," McDougald says. "I will always remember Joyce standing over lab tables, cutting up chicken guts and conducting coccidiosis lesion scoring."

Greg Mathis, SPR president, is quick to point out that Johnson's professional reputation spanned the globe. During her enviable, exemplary career, she traveled to many countries, including Canada, Mexico, Venezuela, Peru, Brazil, England and France, to teach international colleagues her fine art of lesion scoring.

"In 1999 I visited a commercial poultry operation in Venezuela," Mathis relates. "In the company's dissecting room, I saw a photograph of Joyce hanging on the wall. She had been there about 15 years before that, teaching employees how to score lesions. After all those years, she was still in their minds and they were still under her influence."

"Joyce was a patient, persevering person and very low key in her approach," adds consulting parasitologist Donal Conway, Asbury, N.J. "She was an excellent teacher and a real leader. Those qualities were the outstanding part of her popularity and mystique. She always welcomed newcomers to her lab and took them under her wing, no pun intended."

'Walking Repository'

Besides lesion scoring, Johnson was involved with other poultry health issues, including UGA gnotiobiotic research emphasizing Histomonas and nematodes of chickens. While working with Long, she helped to develop chicken coccidia for use in broiler vaccines. Johnson also attenuated strains of coccidia that lose some of their pathogenicity when propagated in chicken eggs.

"She was a walking repository of all of the information on coccidiosis," McDougald emphasizes, noting that Johnson co-authored 44 research papers and four book chapters.

At SPR, Johnson helped design a number of important research protocols, including immunity studies that in 1997 led to the commercial introduction of Coccivac-B via the hatchery spray method.

"So many advances in poultry epidemiology and the processing of new scientific ideas were dependent on the quality of work Joyce Johnson was able to sustain throughout her entire career," Conway emphasizes. "Her contributions to the poultry industry were immeasureable."

Source: CocciForum Issue No.3, Schering-Plough Animal Health.

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