Toxicological and Pathological Review of Concurrent Occurrence of Nitrite Toxicity and Swine Fever in Pigs

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Classical swine fever, nitrate toxicity, swine


Background: Plant associated nitrate/nitrite poisoning in buffalo, cattle, goat and sheep had been reported from various parts of the world. Horses and pigs are considered less susceptible to nitrate poisoning. In this study epidemiology of rare outbreak of nitrate poisoning in combination with classical swine fever in a small pig farm was investigated for development of strategies to control and prevent such incidents in future. Materials and Methods: Concurrent infection of nitrate toxicity and classical swine fever were recorded in district Nawanshahar, Punjab. Eight pigs suddenly fell sick and died 2 days after feeding barseem + oats and marriage waste food. Twelve pigs were sick exhibiting symptoms of anorexia, fever (104-105oF), depression, constipation followed by diarrhea, respiratory difficulty, tremors and staggering gait with recumbency in four completely off"‘feed pigs. Blotchy discolorations of the skin of extremities (ears and snout) were observed in three pigs. Results: Hematological examination revealed marked leucopenia. Postmortem examination revealed dark brown colored blood evident on opening the carcass and presence of barseem, oats in stomach and intestines. Lymph nodes were swollen and hemorrhagic. Serosal surface of spleen show various infarcts and button ulcers were recorded in cecum and colon, pathognomic lesion of classical swine fever. Nitrate toxicity was confirmed on the basis of quantitative determination of nitrate in the biological material of sick and dead animals. Fodder samples were (barseem + oats) positive for diphenylamine blue (DPB) test, Nitrate concentration in offended barseem and oats were found to be 2612 ppm and 3344 ppm as nitrate nitrogen (No3"‘N), respectively. Excessive amount of nitrate in stomach contents (924-1365 ppm), liver (22-48 ppm) and kidney (17-22 ppm) of dead animals (n = 8) confirmed that death of pigs was due to toxicity induced by nitrate/nitrite. Conclusion: The green fodder should be used cautiously in pigs and screening of fodder with DPB test prior offering to animals is strongly recommended to contain the nitrate/nitrite toxicity risk.


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Kaur Sidhu, P., Mahajan, V., Verma, S., ., A., & Partap Gupta, M. (2018). Toxicological and Pathological Review of Concurrent Occurrence of Nitrite Toxicity and Swine Fever in Pigs. Toxicology International, 21(2), 186–190. Retrieved from



Original Research
Received 2018-04-26
Accepted 2018-04-26
Published 2018-04-26



Toxicology: Nitrate and nitrite poisoning. In: Kahn CM, Line S, editors. The Merck Veterinary Manual. 9th ed. Whitehouse Station: Merck and Co; 2005. p. 2423"‘6.

Sidhu PK, Bedi GK, Meenakshi, Mahajan V, Sharma S, Sandhu KS, et al. Evaluation of factors contributing to excessive nitrate accumulation in fodder crops leading to ill"‘health in dairy animals. Toxicol Int 2011;18:22"‘6.

Fairnie IJ. Nitrite poisoning in sheep due to capeweed (Arctotheca Calendula). Aust Vet J 1969;45:78"‘9.

O'Hara PJ, Fraser AJ. Nitrate poisoning in cattle grazing crops. N Z Vet J 1975;23:45"‘53.

Egyed MN, Hanji V. Factors contributing to recent outbreaks of acute nitrate poisoning in farm ruminants. Israel J Vet Med 1987;43:50"‘5.

Vermunt J, Visser R. Nitrate toxicity in cattle. N Z Vet J 1987;35:136"‘7.

Carrigan MJ, Gardner IA. Nitrate poisoning in cattle fed Sudax (Sorghum sp. Hybrid) hay. Aust Vet J 1982;59:155"‘7.

Sidhu PK, Bedi G, Verma S, Meenakshi, Sandhu KS. Investigations and clinical management of nitrate toxicities in dairy animals. Indian Vet J 2008;85:605"‘7.

Al"‘Qudah KM, Rousan LM, Ereifej KI. Nitrate/nitrite poisoning in dairy cattle associated with consumption of forages irrigated with municipally treated wastewater. Toxicol Environ Chem 2009;91:163"‘70.

Radostits OM, Gay CC, Blood DC, Hinchcliff KW. In: A Textbook of Veterinary Medicine (Diseases of Cattle, Sheep, Pigs, Goats and Horses). 9th ed. Philadelphia: W.B. Saunders Co.; 2000. p.1636-9.

McParland PJ, McRory FJ, Bell N, Walls TJ, Manson WH. Nitrite poisoning in pigs. Vet Rec 1980;106:201.

Wiese WJ, Joubert JP. Suspected nitrite poisoning in pigs caused by Capsella bursa"‘pastoris (L.) Medik. (herderstassie, shepherd's purse). J S Af Vet Assoc 2001;72:170"‘1.

Vyt P, Spruytte H. Nitrite intoxication in sows. Vet Rec 2006;158:456.

Barman NN, Nath AJ, Hazarika MP, Barman B, Thakuria D. Outbreak of classical swine fever in regularly vaccinated pig herd. Indian J Comp Microbiol Infect Dis 2003;24:89"‘90.

Kumar H, Mahajan V, Sharma S, Alka, Singh R, Arora K, et al. Concurrent pasteurellosis and classical swine fever in Indian pigs. J Swine Health Prod 2007;15:279"‘83.

Rathnapraba S, Vadivoo VS, Manoharan S, Logesh K, Kumanan K. Molecular detection of classical swine fever from a field outbreak in Tamil Nadu. Indian J Vet Pathol 2012;36:22"‘7.

Cataldo DA, Harron M, Schrader LE, Youngs VC. Rapid colorimetric determination of nitrate in plant, tissue by titration of salicylic acid. Commun Soil Sci Plant Anal 1975;6:71"‘80.

Guevara I, Iwanejko J, Dembinska"‘Kiec A, Pankiewicz J, Wanat A, Anna P, et al. Determination of nitrite/nitrate in human biological material by the simple Griess reaction. Clin Chim Acta 1998;274:177"‘88.

Smith JE, Beutler E. Methemoglobin formation and reduction in man and various animal species. Am J Physiol 1966;210:347"‘50.

Routine staining procedure. In: Luna LG, editor. Manual of Histologic Staining Methods of the Armed Forces. 3rd ed. New York: McGraw"‘Hill Book Company, Blakiston Division; 1968. p. 32"‘9.

Clarke ML, Harvey DG, Humphreys DJ. Veterinary Toxicology. 2nd ed. London: Bailliere Tindall; 1981. p. 89-93.

Agar NS, Harley JD. Erythrocytic methaemoglobin reductases of various animal species. Experientia 1972;28:1248"‘9.

Rockwood GA, Armstrong KR, Baskin SI. Species comparison of methemoglobin reductase. Exp Biol Med (Maywood) 2003;228:79"‘83.

Lapidge SJ, Eason CT. Pharmacokinetics and methaemoglobin reductase activity as determinants of species susceptibility and non"‘target risks from sodium nitrite manufactured feral pig baits. Report for the Australian Government Department of the Environment, Water, Heritage and the Arts. Canberra, Australia.

Sato M, Mikami O, Kobayashi M, Nakajima Y. Apoptosis in the lymphatic organs of piglets inoculated with classical swine fever virus. Vet Microbiol 2000;75:1"‘9.