- Broiler chickens submitted to the Animal Diagnostic Laboratory between February and May 2012 showed problems with leg weakness and lameness. - The majority of cases had concurrent bacterial infections like E. coli, Enterococcus cecorum, and Salmonella enteritidis along with reovirus infection. Only 16% had solely reovirus. - The bacterial infections were causing issues like polyserositis, septicemia, osteomyelitis, and septic arthritis in the legs at different ages of the broilers. Reovirus infection may have contributed to immunosuppression and secondary bacterial infections in the legs.

1. CONCURRENT LEGCONCURRENT LEGCONCURRENT LEGCONCURRENT LEG
PROBLEMS IN BROILERSPROBLEMS IN BROILERS
WITH REOVIRUSWITH REOVIRUS
INFECTIONINFECTION
Drs. Eva WallnerDrs. Eva Wallner--Pendleton,Pendleton,
PatriciaPatricia Dunn,Dunn, SubhashinieSubhashinie
Kari a asam andKari a asam and H ag ang LH ag ang LKariyawasam andKariyawasam and Huaguang LuHuaguang Lu
The Pennsylvania StateThe Pennsylvania State
University, Animal DiagnosticUniversity, Animal Diagnostic
LaboratoryLaboratory--PADLSPADLS

2. INVESTIGATION TIMELINEINVESTIGATION TIMELINEINVESTIGATION TIMELINEINVESTIGATION TIMELINE
Commercial broilersCommercial broilersCommercial broilersCommercial broilers
submitted for “lameness”submitted for “lameness”
or “splayor “splay--leg” problemsleg” problemsor splayor splay leg problemsleg problems
or uneven growth.or uneven growth.
Necropsy casesNecropsy casesNecropsy casesNecropsy cases
submitted betweensubmitted between
FebruaryFebruary present 2012present 2012FebruaryFebruary ––present 2012present 2012
“Approximately” 40“Approximately” 40
fl k ADLfl k ADLflocks seen at ADLflocks seen at ADL

3. AGE RANGE OF NECROPSYAGE RANGE OF NECROPSY
SUBMISSIONSSUBMISSIONSSUBMISSIONSSUBMISSIONS
11% = days 111% = days 1--141411% days 111% days 1--1414
26% = days 1526% = days 15--2121
20% 2220% 22 282820% = days 2220% = days 22--2828
23% = days 2923% = days 29--3636
20% = days 37+20% = days 37+

4. Lameness Problems SeenLameness Problems Seen
According To AgeAccording To AgeAccording To AgeAccording To Age
Most groups had some coccidiosisMost groups had some coccidiosisg pg p
present (litter eating??), valguspresent (litter eating??), valgus
deformation and splaydeformation and splay--legslegsp yp y gg
11--14 days14 days
Bacterial yolk sac infection, polyserositis andBacterial yolk sac infection, polyserositis andacte a yo sac ect o , po yse os t s a dacte a yo sac ect o , po yse os t s a d
septic arthritisseptic arthritis
S. enteritidisS. enteritidis
Femoral head necrosisFemoral head necrosisFemoral head necrosisFemoral head necrosis
TD lesionsTD lesions
Aspergillosis in jointsAspergillosis in joints

5. Lameness Problems SeenLameness Problems Seen
A di T AA di T AAccording To AgeAccording To Age
1515--21 days21 days1515 21 days21 days
E. cecorumE. cecorum myositis and septicemiamyositis and septicemia
E. coliE. coli polyserositis and cellulitis and septicpolyserositis and cellulitis and septic
th itith itiarthritisarthritis
OsteomyelitisOsteomyelitis
Femoral head necrosisFemoral head necrosis
2222--28 days28 days
E. coliE. coli polyserositis and purulent arthritispolyserositis and purulent arthritis
Staphylococcus septic arthritisStaphylococcus septic arthritis
E. cecorumE. cecorum septicemiasepticemia
S. thompsonS. thompson infectioninfectionS. thompsonS. thompson infectioninfection
Femoral head necrosisFemoral head necrosis

6. Lameness Problems SeenLameness Problems Seen
A di T AA di T AAccording To AgeAccording To Age
2929--36 days36 days2929--36 days36 days
Osteomyelitis and condritisOsteomyelitis and condritis
E. cecorumE. cecorumE. cecorumE. cecorum
37 and up37 and up
F l h d iF l h d iFemoral head necrosisFemoral head necrosis
E. coliE. coli osteomyelitisosteomyelitis
Staphylococcus in jointsStaphylococcus in jointsStaphylococcus in jointsStaphylococcus in joints

7. Typical Lameness Seen in TheTypical Lameness Seen in The
ChicksChicks

8. MOST COMMON LEG PROBLEMMOST COMMON LEG PROBLEM
OBSERVED DURING TIME FRAMEOBSERVED DURING TIME FRAMEOBSERVED DURING TIME FRAMEOBSERVED DURING TIME FRAME
E.O. OviedoE.O. Oviedo--Rondon, NC Broiler Supervisor’s Short Course, 2008.Rondon, NC Broiler Supervisor’s Short Course, 2008.

9. Initially, Developmental ProblemInitially, Developmental Problem
Assumed Causing the Splay LegsAssumed Causing the Splay Legs
and Valgus Deformationand Valgus Deformation
High humidity during incubation.High humidity during incubation.
High temperatures during the last phase ofHigh temperatures during the last phase of
embryo development.embryo development.
Placing newly hatched chicks on slipperyPlacing newly hatched chicks on slipperyPlacing newly hatched chicks on slipperyPlacing newly hatched chicks on slippery
surfaces.surfaces.
Muscle weakness, bone, cartilage and tendonMuscle weakness, bone, cartilage and tendon
development affected by incubationdevelopment affected by incubation
conditions.conditions.
Hip joint especially affectedHip joint especially affectedHip joint especially affected.Hip joint especially affected.
E. O. OviedoE. O. Oviedo--Rondon and Wineland. World Poultry. vol 27, no.Rondon and Wineland. World Poultry. vol 27, no.
5, 2011.5, 2011.

10. Polyserositis/septicemia, yolk sacPolyserositis/septicemia, yolk sac
infections:infections: E. coliE. coli,, Salmonella enteritidisSalmonella enteritidis,,,, ,,
Enterococcus cecorumEnterococcus cecorum

11. Other Common FindingsOther Common FindingsOther Common FindingsOther Common Findings
--MyositisMyositisyy
--OsteomyelitisOsteomyelitis
(bone infection)(bone infection)
--Septic arthritisSeptic arthritis
EnterococcusEnterococcusEnterococcusEnterococcus
cecorumcecorum,, E.E.
coli,coli,
StaphylococcusStaphylococcus
sometimessometimes
isolatedisolated
Osteomyelitis
isolatedisolated

12. Septic arthritis, tenosynovitisSeptic arthritis, tenosynovitisSeptic arthritis, tenosynovitisSeptic arthritis, tenosynovitis

13. Femoral Head NecrosisFemoral Head NecrosisFemoral Head NecrosisFemoral Head Necrosis
Bacterial infection ofBacterial infection of
the growth platethe growth plate
cartilage and bone incartilage and bone in
the femoral headthe femoral headthe femoral head,the femoral head,
causing it to fracture.causing it to fracture.
Can be nonCan be non--infectiousinfectious
as well secondary toas well secondary to
rickets orrickets orrickets orrickets or
osteoporosis.osteoporosis.

14. Tibial dyschondroplasiaTibial dyschondroplasiaTibial dyschondroplasiaTibial dyschondroplasia
Failure of the growthFailure of the growth
l t til ll tl t til ll tplate cartilage cells toplate cartilage cells to
develop normally and adevelop normally and a
cartilage plug remainscartilage plug remainscartilage plug remains.cartilage plug remains.
Affected joint oftenAffected joint often
enlarged, some bowingenlarged, some bowingenlarged, some bowingenlarged, some bowing
of legs may occur.of legs may occur.
Painful if plug is large.Painful if plug is large.Painful if plug is large.Painful if plug is large.
Nutritional/geneticNutritional/genetic
causes probable.causes probable.pp

15. DiscussionDiscussion
84 % of submitted reovirus84 % of submitted reovirus
positive cases had otherpositive cases had other
(primarily bacterial) leg(primarily bacterial) leg(primarily bacterial) leg(primarily bacterial) leg
problems as well.problems as well.
16 % had only reovirus16 % had only reovirus16 % had only reovirus16 % had only reovirus
infection.infection.
These diseases probably existThese diseases probably existThese diseases probably existThese diseases probably exist
in very low levels in any flock.in very low levels in any flock.
L i d b thL i d b thLesions caused by theLesions caused by the
virus/immunosuppression mayvirus/immunosuppression may
have played a role in thesehave played a role in these
secondary infectionssecondary infectionssecondary infections.secondary infections.