COCCIDIOSIS CONTROL approvals of 3-way combinations based on the. "reduction of lesions caused by E. tenella", and on improved pigmentation [4].
(81992 Applied Pouluy Scienw, Inc
How MUCHDOESROXARSONE CONTRIBUTE TO COCCIDIOSIS CONTROL IN BROILERS WHEN USED IN COMBINATION WITH IONOPHORES? LARRY R. MCDOUGALD~,JEFFREY M. GILBERT,LORRAINE FULLER, AYO ROTIBI, MINGQUAN XIE and GUAN ZHU Department of Poultry Science, Universityof Georgia, Athens, GA 30602 Phone: (706) 542-1367 F M : (706) 542-1377
Primary Audience: Poultry Health Managers, Veterinarians, Nutritionists, Scientists in Animal Health Companies, Production Managers, Researchers Studying Feed Additives and Combinations of Feed Ingredients for Growth Promotion and Feed Efficiencv
DESCRIPTION OF PROBLEM Roxarsone has been used since the early 1950's for growth promotion [l] despite the
fact that much of its early use was for control and prevention of coccidiosis caused by Eimeria tenella [2]. More recently some efficacy against E. brunetti has been found [3], and also
1
To whom correspondence should be addressed
some improvement in skin pigmentation. The use of "3-way"combinations of roxarsone, an anticoccidial, and an antibiotic growth promoter have resulted in only marginal improvements in growth and/or feed conversion. However, in many instances, FDA has granted
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COCCIDIOSIS CONTROL
approvals of 3-way combinations based on the "reduction of lesions caused by E. tenella",and on improved pigmentation [4]. Producers have apparently overcome skepticism about t h e effectiveness of roxarsone caused by recent negative research reports [5],because today most broilers in the USA receive roxarsone. The widespread acceptance of roxarsone, despite its marginal effectiveness as a growth promoter, suggests that other qualities, such as anticoccidial activity, may be more important. The declining efficacy of ionophores in recent years has caused concerns about possible interaction of subclinical coccidiosis with other diseases or conditions [6], or possible increases in colonization by SalmoIn this study, we examine the antinella coccidial properties of roxarsone against several recent field isolates of coccidia, including E. tenella, E. maxima, E. acenulina and E. brunetti, especially in combination with ionophores.
[I.
MATERIALS
PRODUCTS EVALUATED Commercial premixes of anticoccidial products were obtained from manufacturers and mixed with unmedicated broiler starter ration (23% protein, 1434 KcaVlb) to produce recommended levels of drugs (see figure legends).
RESULTS AND DISCUSSION TITRATION OF ROXARSONE AGAINST FIELD ISOLATES OF Eimeria tenella Roxarsone had little anticoccidial efficacy against a field isolate of E. tenella at 22.4 @ton, but improvements in weights and lesion scores were apparent at 45.4 @ton (Figure 1). Improvements were also seen in lesion scores at higher levels, but the weight was depressed above 90.8 @ton. Several isolates were tested with similar results, but isolates were also found which did not respond. EFFECT O F ROXARSONE AGAINST E. maxima Three isolates of E. maxima were tested for response to 45.5 @ton of roxarsone. There was no apparent improvement in lesion scores with the bse of roxarsone (Figure 2), but there was some improvement in weight gain of infected birds.
AND METHODS
FIELD ISOLATES OF COCCIDIA Various mixed species of coccidia from broilers were isolated from samples of fresh droppings collected on farms in various parts of the USA as described previously [8]. Cultures were selected which were predominantly E . maxima, E. acervulina, E . tenella or E. brunetti. The inoculum for various experiments included either 10,000, 40,000 or 100,000 oocysts of E. tenella, 200,000 of E. brunetti, 200,000of E. maxima, or 500,000 of E. acenulina. EFFICACY TEST IN CHICKENS Groups of fourteen-day-oldbroiler chicks in laboratory cages were given the test feeds (see below) for two days prior to inoculation with coccidia. Test feeds were fed until termination of the experiments. Each treatment was replicated in four cages of nine or ten birds each. Experiments were terminated six days postinoculation, when all birds were killed for necropsy and lesion scoring [9]. Weight gain (from time of infection to termination), lesion scores, and sometimes oocyst counts, were recorded as measures of the infection.
EFFECT OF ROXARSONE AGAINST E. brunetti Roxarsone reduced the lesion scores by 51% and improved weight gain to exceed that of the uninfected control in birds infected with a field isolate of E. brunetti (Figure 3). E F F E C T O F ROXARSONE ON E. acervulina Five isolates of E. acenulina were tested against roxarsone at 45.4 @ton. The lesion scores were not reduced by roxarsone, but weight gains were usually improved (Figure 4). EFFECT OF ROXARSONE ON OOCYST PRODUCTION The reproduction of coccidia was reduced in birds infected with E.tenella, E. maxima, E. acervulina or E. brunetti when roxarsone was given at 45.4 @ton (Figure 5).
Research Report MCDOUGALD et ai.
174
C O N T R O L O F COCCIDIOSIS BY IONOPHORES SEPARATELY AND COMBINED WITH ROXARSONE An ionophore-tolerant isolate of E. tenella was not controlled by monensin or salinomycin (Figure 6). Roxarsone alone reduced the lesion scores by more than 50% and, when combined with either monensin or salinomycin, reduced the lesion scores even further. This effect was prominent whether a mild infection (l0,OOO oocystsbird) or a severe infection (lO0,OOO oocystsbird) was given. This same isolate was controlled to a better extent by maduramicin and narasin (Figure 7). T h e addition of roxarsone t o e i t h e r maduramicin or narasin reduced lesion scores even further. However, improvement was
modest because of the magnitude of the effect of these two ionophores when used without roxarsone. Results were similar in mild and severe infections. COMBINATION O F ROXARSONE W I T H I O N O P H O R E S A N D NONIONOPHORES AGAINST FIELD ISOLATES Isolates of coccidia containing E. tenella, E. acervulina, and E. maxima were tested against 10 anticoccidial drugs, with or without roxarsone. The results of these tests were variable, because of the differences in prior exposure of the coccidia to drugs at different locations, but clearly showed the value of roxarsone (Figure 8).
Average Wt. Gain (9)
Cecal Lesion Score
250
3.5 3
200 2.5 150
2
1.5
100
1
50
0.5 0
0 NMI
22.7
45.4
90.8
181.6
NMU
Roxarsone Level (glton) FIGURE 1. Titration of roxarsone against a field isolate of Fimeria tenella from Virginia. (NMI = nonmedicated, infected control; NMU = nonmedicated, uninfected control).
COCCIDIOSIS CONTROL
175
4
Average Lesion Score
Average Wt. Gain (9)
200
3.5 150
3 2.5
100
2 1.5
50
1
0.5 0
0 NMU
NMI
45.4
ROXARSONE LEVEL (g/ton)
I
Weight Gain
Lesion Score
~
FIGURE 2. Effect of roxarsone on a field isolate of E.maxima: average weight gain and average lesion scores. (NMU = nonrnedicated, uninfected control; NMI = nonmedicated, infected control).
Average Wt. Gain (9)
AVERAGE LESION SCORE
3
300
2.5
250
2
200
1.5
150
1
0.5
I-
-
100
50
Lesion Score
0
Weight Qain
0 NMU
NMI
ROX
FIGURE 3. Effect of roxarsone on a field isolate of E.brunetti: average weight gain and average lesion scores. (NMU = nonmedicated, uninfected control: NMI = nonmedicated, infected control).
Research Report 176
MCDOUGALD et al.
Average Wt. Gain (9) . I200
Average Lesion Score
- 150
- 100
- 50
I
I
-Weight
Gain (g)
Lesion Score
NMU
NMI
45.4
J, -
ROXARSONE LEVEL (g/ton) FIGURE 4. Effect of roxarsone on afield isolate of E.acervulim: Average weight gain and average lesion scores. (NMU = nonmedicated, uninfected control: NMI = nonmedicated, infected control).
OOCYSTS/BIRD X 10E6 100 I 0 PPM
E. acervulina
E. brunetti
m 5 0 PPM
E. -tenella
FIGURE 5. Effect of roxamne on oocyst shedding of birds infected with and E.m a x i m .
E.
0100 PPM
E. maxima
E.a w u lins, E.kmmetli,
JAPR 177
COCCIDIOSIS CONTROL AVERAGE LESION SCORE
3.5
I
32.5 -
21.5 10.5 -
0NMI
ROX
SAL
I=
10,00O/BIRD
SAL+ROX
40,00O/BIRD
MON
MON+ROX
0100,00O/BIRD
~
FlGURE6. Effectivenessof roxarsone (ROX, 45.4 g/ton) in combination with salinomycin (SAL, -/ton) and monensin (MON, 100 gfion) for control of a field isolate of E. from Virginia at 3 inoculum levels (lO,OOO, 40,000 or 100,OOO oocystsbird). (NMU = nonmeidated, uninfected control; NMI = nonmedicated, infected control) (S R = Salinomycin Roxarsone, M R = Monensin Roxarsone).
+
+
+
+
Average Lesion Score
3.5 ,000/Blrd
40,00O/BIrd
100,00O/Bird
3 2.5
2 1.5 1
0.5 0 NMI
ROX
MAD
MAD+ROX
NAR
NAR+ROX
FIGURE 7. Effectiveness of roxarsone (ROX, 45.4 g/ton) in combination with maduramicin (MAD, 4.5 g/ton) and narasin (NAR, 72 ghon) for control of a field isolate of E.&m!Jafrom Virginia at 3 inoculum levels (lO,OOO, 40,OOO or 100,OOO oocysts/bird). (NMU = noinmedicated, uninfected control; NMI = nonmedicated, infected control).
Research Report MCDOUGALD et ai.
178
Average Lesion Score 51
NMI
LAS MON NAR SAL MAD DEC CLO NIC MAX HAL ROX
1
DRUG+ROXARSONE
@%DRUG ALONE
1
FIGURE 8. Effectiveness of 10 anticoccidial products and the additive effects of roxarsone against a field isolate of coccidia from California. (NMI = nonmedicated, infected control; LAS = lasalocid, 90 gAon; MON = monensin, 100 g/ton; NAR = narasin, 72 g/ton; SAL = salinomycin, 60 g/ton; MAD = maduramicin, 4.5 g/ton; DEC = decoquinate, 27 g/ton; CLO = clopidol, 113 g/ton; NIC = nicarbazin, 113 g/ton; MAX = maxiban, NAR:NIC - 36:36 g/ton; HAL = halofuginone, 2.7 g/ton; ROX = roxarsone, 45.4 g/ton).
CONCLUSIONS AND APPLICATIONS 1. Roxarsone had significant activity against E. tenella and E. brunetfi and contributed to the
control of these coccidia when used in combination with ionophores. 2. Levels of roxarsone below 45.4 @ton did not appear to offer anticoccidial protection, while levels above 45.4 g/ton depressed weight. 3. Even though control of E. acenulina and E. maxima appeared marginal on the basis of lesion score reduction, roxarsone probably works late in the life cycle of these parasites, as shown by reduction in oocyst shedding and overall improvement in birds infected with mixed field isolates. 4. Not all field isolates responded as well to roxarsone, suggesting that results might vary greatly from one location to another under field conditions. 5. The anticoccidial properties of roxarsone are more than adequate to justify its routine use in broilers at 45.4 @ton.
REFERENCES AND NOTES 1. Morehouse, N.F., 1949. Accelerated growth in chickens and turkeys roduced by 3-nitro-4hydroxyphenylarsonicacid. foultry Sci. 28:375-384.
2. Morehouse, N.F., and McKay, F., 1951.Action of 3-nitro~-h~droxyphenylarsonicacid a ainst Eimeria lenella in chic ens. owa Acad. Sci. 5850$-516.
3. Kowalski, LM., and Reid, W.M., 1975. Effects of roxarsone on pi entation and coccidiosis in broilers. Poultry Sci. 54:1!%-1549. 4. Feed Addilives Compendium, 1991. Miller Publishing Co.,Minneapolis, MN (Updated monthly).
JAPR 179 5. Dilhvorlh, B.C., andDay, EJ.,1985. Survey of the u s e s of 3-Nitro in b r o i l e r diets. Poultry Sci. 64(Suppl. 1):17. (Abs) 6. Ruff, M.D.,1990. Interactions of low levels of coccidiosis with other diseases. Proc. 25th Natl. Mtg. on Poultry Health and Condemnations. pp. 115-121. 7. h k a w n , A, Baba, E, and Fukata, T., 1981. Eimeria tenella infection enhances Salmonella typhimurium infection in chickens. Poultry Sci. M):2203-2209.
COCCIDIOSIS CONTROL 8. Mc"ugaId, LR, Fuller, L, and Solis, J., 1986. Drug-sensitiwty of 99 isolates of coccidia from broiler farms. Avian Dis. u):690-694. 9. Johnson,J.K., and Reid, W.M., 1970. Anticoccidial drugs: Lesion scorin techniques in battery and floorriments with ctickens. Experimental Parasitol.
%?il2F
10. We wish to thank Rhone-Poulenc, Inc., 500 Northridge Road, Atlanta, GA 30350, for financial support of this project.
