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Analysis of Morbidity and Mortality of Important Diseases of Swine in Mizoram State of India

J. K. Chaudhary N. Shyamsana Singh T. C. Tolenkhomba S. K. Behera Vanlalchhuanga
Vol 9(1),324-335
DOI- http://dx.doi.org/10.5455/ijlr.20180901045842

In the present study, a structured sampling design was adopted, which covered the major regions of the Mizoram state, to ascertain the morbidity and mortality rates of important diseases. The overall annual morbidity, mortality and case fatality rates have been estimated from the sample as 33.50%, 20.57% and 61.41%, respectively. Major causes of morbidity were reproductive diseases (aborted fetus), followed by Classical swine fever and major cause of mortality were also reproductive diseases (aborted fetus) followed by Classical swine fever and respiratory diseases. The case fatality rate was highest for poisoning followed by reproductive diseases (aborted fetus), injury & accidents and classical swine fever. Aborted fetuses were the major challenges under village condition in study area, so major emphasis should led to attend the reproductive problems.


Keywords : Classical Swine Fever Morbidity Rate Mortality Rate Reproductive Diseases

Pig husbandry is a profitable occupation, especially for small and marginal farmers. It requires minimum capital investment and labour. The pig industry success depends on health of the pigs and any compromise on health ground will shatter the hope of piggery sector. Total livestock population of Mizoram was 0.31 Million (19th Live Stock Census, Department of Animal Husbandry, Dairying and Fisheries, 2012). Among the total livestock, Pigs contributes highest with 78.64% followed by cattle 11.09%, goat 7.12%, buffalo 1.66% besides marginal contribution is attributed by other livestock species such as sheep, camel,  mules, donkeys, horses and ponies. The total number of pigs in the state as per census 2012 is 0.24 million numbers.

The knowledge of prevalent diseases and causes of morbidity and mortality are very important for managing pig farms efficiently. Keeping the above points in view and for better understanding the disease free production process the present study; efforts have been made for analysis of morbidity and mortality of important diseases of swine in Mizoram state of India using the sample survey data.

Materials and Methods                                                    

Selection of Study Area

The present study was conducted in Mizoram. The reason of choosing Mizoram as the research area is that the different diseases like Classical Swine Fever (CSF), Foot and Mouth Disease (FMD), Digestive diseases, Respiratory diseases and Metabolic & nutritional deficiency etc. are causing a great morbidity and mortality that led to high production and economic losses (Deka et al., 2008).

Sampling Design

Mizoram has 8 districts that were divided into two agro-climatic zones. By taking two agro-climatic zones as strata, two districts each from zone 1 & zone 2 were selected randomly. From each selected districts two blocks and from each selected blocks, two villages were selected by simple random sampling without replacement scheme. A total of 15 pig owners have been selected from each selected village & thus a total 240 pig owners constitute the ultimate sample from sixteen villages and eight blocks for the study. The sampling scheme followed in the present study is stratified three-stage random sampling.

Data

The researchers contacted the local Government Veterinary Officer in each of the administrative blocks where the survey was being carried out, to explain the objectives of the survey. Each  household  selected  for  the  sample  was  surveyed to collect detailed information using a questionnaire, supported  by a disease identification checklist based on clinical symptoms  and  photographs. Data were collected between September, 2017 and July, 2018.

Statistical Analysis

The data were analyzed by SPSS (version 17) program to compute the results.

Results and Discussion

The overall annual morbidity and mortality rates in Mizoram state have been estimated from the sample as 33.50% and 20.57% respectively (Fig. 1). Out of the total morbidity rates, highest is for reproductive diseases (aborted fetus), 8.77% followed by Classical swine fever (8.35%), parasitic diseases (5.36%), respiratory diseases (5.03%), digestive diseases (4.78%), injury & accidents (0.75%) and poisoning (0.46%).

Fig. 1: Overall morbidity & mortality rates in Pigs

Out of the total mortality rates, highest is for reproductive diseases (aborted fetus), 8.69% followed by Classical swine fever (5.07%), respiratory diseases (2.04%), digestive diseases (1.87%), parasitic diseases (1.83%), injury & accidents (0.62%) and poisoning (0.46%). Overall case fatality rate was 61.41%. The case fatality rate was highest for poisoning (100%) followed by reproductive diseases (aborted fetus) 99.05%, injury & accidents 83.33%, classical swine fever (60.70%), respiratory diseases (40.5%), digestive diseases (39.13%) and parasitic diseases (34.11%) (Table 1).

Table 1: Overall morbidity and mortality rates due to different diseases in swine population of Mizoram state

Disease Population at risk Cases Deaths Morbidity Rates (%) Mortality Rates (%) Case Fatality Rates (%)
Specific Disease (Classical Swine fever) 2406 201 122 8.35 5.07 60.7
Reproductive diseases (Aborted Fetus) 211 209 8.77 8.69 99.05
Parasitic diseases 129 44 5.36 1.83 34.11
Respiratory diseases (Coughing & Pneumonia) 121 49 5.03 2.04 40.5
Digestive diseases (Diarrhoea) 115 45 4.78 1.87 39.13
Injury & Accidents 18 15 0.75 0.62 83.33
Poisoning 11 11 0.46 0.46 100
Total 2406 806 495 33.5 20.57 61.41

 

Fig. 2: Mobidity & Mortality rates of different diseases in pigs

 

Fig. 3: Case fatality rates of different diseases in pigs

The incidence rate may vary across age group, sex and season. The morbidity rates were highest in piglets (41.87%) followed by young (19.33%) and adults (14.47%). The morbidity rate for classical swine fever was more in young one (14.20%) followed by piglets (7.40%) and adults (3.77%) (Table 2).

 

 

Table 2: Age wise morbidity rate in swine population

Disease Piglets Young Adults χ2cal
Cases % Cases % Cases %
Specific Disease (Classical Swine fever) 117 7.4 72 14.2 12 3.77 χ2 =33.23**
χ212 =21.57**
χ213 = 5.5*
χ223 = 23.24**
Reproductive diseases (Aborted Fetus) 201 12.71 0 0 10 3.14 χ2 = 24.54**
χ213 = 24.54**
Parasitic diseases 111 7.02 3 0.59 15 4.72 χ2 =31.57**
χ212 =30.74**
χ213 = 2.27
χ223 = 15.58**
Respiratory diseases (Coughing & Pneumonia) 110 6.96 4 0.79 7 2.2 χ2 = 36.72**
χ212 =28.30**
χ213 = 10.36**
χ223 = 2.96
Digestive diseases (Diarrhoea) 95 6.01 18 3.55 2 0.63 χ2 = 18.97**
χ212 =4.53*
χ213 = 15.81**
χ223 = 7.05**
Injury & Accidents 18 1.14 0 0 0 0
Poisoning 10 0.63 1 0.2 0 0
Total 662 41.87 98 19.33 46 14.47 χ2 = 147.17**
χ212 =84.27*
χ213 = 85.05**
χ223 = 3.21
Total No. available 1581 507 318   

The cell containing zero is excluded in χ2 calculation; * Significantly Different (p<0.05), ** Significantly Different (p<0.01)

The morbidity rates were slightly higher in male (34.96 %) than female (31.86%) (Table 3).

Table 3: Gender wise morbidity rate in swine population

Disease Male Female χ2cal
Cases % Cases %
Specific Disease (Classical Swine fever) 104 8.17 97 8.56 0.12
Reproductive diseases (Aborted Fetus) 115 9.03 96 8.47 0.59
Parasitic diseases 61 4.79 68 6 1.73
Respiratory diseases (Coughing & Pneumonia) 63 4.95 58 5.12 0.036
Digestive diseases (Diarrhoea) 92 7.23 23 2.03 35.57**
Injury & Accidents 6 0.47 12 1.06 2.79
Poisoning 4 0.31 7 0.62 1.21
Total 445 34.96 361 31.86 2.58
Total No. available 1273   1133    

 

Fig. 4: Mobidity & mortality rates in pig by age group

Fig. 5: Mobidity and mortality rates in pig by sex

The morbidity rates were highest in rainy season (14.55%) followed by winter (10.97%) and summer (7.98%) (Table 4).

 

 

Table 4: Season wise morbidity rates in swine population

Disease Summer Winter Rainy χ2cal
Cases % Cases % Cases %
Specific Disease (Classical Swine fever) 79 3.28 25 1.04 97 4.03 62.13**
Reproductive diseases (Aborted Fetus) 72 2.99 73 3.03 66 2.74 22.74**
Parasitic diseases 18 0.75 18 0.75 93 3.87 51.92**
Respiratory diseases (Coughing & Pneumonia) 0 0 89 3.7 32 1.33 57.41**
Digestive diseases (Diarrhoea) 13 0.54 56 2.33 46 1.91 19.59**
Injury & Accidents 5 0.21 3 0.12 10 0.42 2.2
Poisoning 5 0.21 0 0 6 0.25 0.49
Total 192 7.98 264 10.97 350 14.55  
Total number available 2406            

 

Fig. 6: Season wise Morbidity & Mortality rates in Pig

The logistic regression analysis with respect of classical swine fever revealed significant (p<0.01) difference in morbidity rate between age and sex. The logistic regression analysis revealed that young animal (OR=1.885) and male animal (OR=1.672) were at higher risk of morbidity (Table 5).

 

 

Table 5: Disease wise (Classical swine fever) logistic regression analysis of morbidity rates

Factors B S.E. Wald df Sig. OR
Age     359.05 2 0  
Piglets -3.492 0.249 197.37 1 0 0.03
Young 0.634 0.31 4.18 1 0.041 1.885
Adults Ref.   1
Male 0.514 0.199 6.679 1 0.01 1.672
Female Ref.   1
Season     0.248 2 0.883  
Summer -0.129 0.269 0.232 1 0.63 0.879
Winter -0.074 0.226 0.106 1 0.744 0.929
Rainy Ref.   1
Constant 1.178 0.27 19.036 1 0 3.247

Nagelkerke R Square= 0.604; OR= odds ratio: Ref= Reference category

The logistic regression analysis with respect of parasitic diseases revealed significant (p<0.01) difference in morbidity rate between age, gender and season. The logistic regression analysis revealed that piglets (OR=1.303) were at higher risk of morbidity than adults and young animal. The analysis showed that male animal (OR=0.675) were at lesser risk of morbidity than female animals. The analysis showed that morbidity is more in rainy season (OR=1.0) than summer (OR=0.357) and winter season (OR=.132) (Table6).

Table 6: Disease wise (parasitic diseases) logistic regression analysis of morbidity rates

Factors B S.E. Wald df Sig. OR
Age     21.134 2 .000  
Piglets .265 .313 .716 1 .397 1.303
Young -2.460 .658 13.994 1 .000 .085
Adults Ref.   1
Male -.421 .204 4.262 1 .039 .657
Female Ref.   1
Season     57.256 2 .000  
Summer -1.029 .284 13.173 1 .000 .357
Winter -2.021 .279 52.414 1 .000 .132
Rainy Ref.   1
Constant -.858 .319 7.211 1 .007 .424

Nagelkerke R Square= 0.235; OR= odds ratio: Ref= Reference category

 

 

 

Table 7: Age wise mortality rate in swine population

Disease Piglets Young Adults χ2cal
Died % Died % Died %
Specific Disease (Classical Swine fever) 71 4.49 45 8.88 6 1.89 χ2 =23.05**
χ212 =14.07**
χ213 = 4.62*
χ223 = 16.46**
Reproductive diseases 201 12.71 0 0 8 2.52 χ2 = 28.11**
(Aborted Fetus) χ213 = 28.11**
Parasitic diseases 35 2.21 3 0.59 6 1.89 χ2 = 5.63
Respiratory diseases (Coughing & Pneumonia) 49 3.1 0 0 0 0
Digestive diseases (Diarrhoea) 40 2.53 5 0.99 0 0 χ2 = 4.34*
χ212 = 4.34*
Injury & Accidents 15 0.95 0 0 0 0
Poisoning 10 0.63 1 0.2 0 0
Total 421 26.63 54 10.65 20 6.29 χ2 = 105.73**
χ212 =55.77**
χ213 = 61.43**
χ223 = 4.55*
Total No. available 1581   507   318  

The incidence rate may vary across age group, sex, season and region. The mortality rates were highest in piglets (26.63%) followed by young (10.65%) and adults (6.29%) (Table 7). The mortality rates were slightly higher in male (20.74 %) than female (20.39%) (Table 8).

Table 8: Gender wise mortality rate in swine population

Disease Male Female χ2cal
Died % Died %
Specific Disease (Classical Swine fever) 58 4.56 64 5.65 1.49
Reproductive diseases (Aborted Fetus) 115 9.03 94 8.3 0.41
Parasitic diseases 27 2.12 17 1.5 1.29
Respiratory diseases (Coughing & Pneumonia) 21 1.65 28 2.47 2.03
Digestive diseases (Diarrhoea) 34 2.67 11 0.97 9.44**
Injury & Accidents 5 0.39 10 0.88 2.32
Poisoning 4 0.31 7 0.62 1.21
Total 264 20.74 231 20.39 0.045
Total No. Available 1273   1133    

 

The mortality rates were highest in rainy season (8.85%) followed by summer (6.53%) and winter (5.20%) (Table 9).

 

 

 

Table 9: Season wise mortality rates in swine population

Disease Summer Winter Rainy χ2cal
Died % Died % Died %
Specific Disease (Classical Swine fever) 52 2.16 11 0.46 59 2.45 24.04**
Reproductive diseases (Aborted Fetus) 72 2.99 72 2.99 65 2.7 24.93**
Parasitic diseases 17 0.71 5 0.21 22 0.91 4.96
Respiratory diseases (Coughing & Pneumonia) 0 0 23 0.96 26 1.08 2.44
Digestive diseases (Diarrhoea) 8 0.33 11 0.46 26 1.08 5.55
Injury & Accidents 3 0.12 3 0.12 9 0.37 1.9
Poisoning 5 0.21 0 0 6 0.25 0.04
Total 157 6.53 125 5.2 213 8.85  
Total No. Available 2406            

 

The logistic regression analysis with respect of classical swine fever revealed significant (p<0.01) difference in mortality rate between age, sex and season. The logistic regression analysis revealed that young animal (OR=22.509) and female animal (OR=1.0) were at higher risk of mortality. The analysis showed that mortality were more in rainy season (OR=1.0) than summer and winter season (Table 10).

Table 10: Disease wise (Classical swine fever) Logistic regression analysis of mortality rates

Factors B S.E. Wald df Sig. OR
Age     65.624 2 0  
Piglets -0.548 0.532 1.063 1 0.303 0.578
Young 3.114 0.65 22.93 1 0 22.509
Adults Ref.   1
Male -0.721 0.255 7.972 1 0.005 0.486
Female Ref.   1
Season     16.908 2 0  
Summer -0.818 0.313 6.822 1 0.009 0.441
Winter -1.36 0.368 13.646 1 0 0.257
Rainy Ref.   1
Constant -0.227 0.53 0.183 1 0.669 0.797

Nagelkerke R Square= 0.331; OR= odds ratio: Ref= Reference category

The logistic regression analysis with respect of digestive diseases revealed significant (p<0.01) difference in mortality rate between age and season. The logistic regression analysis revealed that piglets (OR=20.357) were at higher risk of mortality. The analysis showed that mortality were more in summer season (OR=3.491) followed by winter season (OR=1.348) and rainy season (OR=1.0) (Table 11).

Nandi et al. (2011) also reported that 63.3% of the samples collected from 12 states in India had CSFV antibodies while 76.7% of the samples collected from 13 states had CSFV antigens. The case fatality rates obtained from this study approximate those published by Kumar et al. (2007) but the incidence estimates vary because they measure different but related events. Incidence estimates published by Kumar et al. (2007) represent the number of animals affected in the CSF outbreaks studied while those obtained from this study represent the rate at which villages are affected by CSF outbreaks over a period of one year. All these findings show that young pigs suffer heavier mortalities compared to older animals. Wright et al. (2010) have characterized husbandry systems (feeds, housing, and breeds and breeding) used to raise pigs in north-eastern India. Their observations are very similar to those reported in this study.

Table 11: Disease wise (Reproductive diseases) Logistic regression analysis of mortality rates

Factors B S.E. Wald df Sig. OR
Age     58.397 2 0  
Piglets 3.013 0.394 58.397 1 0 20.357
Young -18.91 3877.12 0 1 0.996 0
Adults Ref.   1
Season     18.935 2 0  
Summer 1.25 0.291 18.429 1 0 3.491
Winter 0.299 0.247 1.464 1 0.226 1.348
Rainy Ref.   1
Constant -3.1 0.426 53.079 1 0 0.045

Nagelkerke R Square = 0.47; OR= odds ratio: Ref= Reference category

Conclusion

The present study has generated information about the morbidity and mortality rates caused by important diseases in pigs in Mizoram state of India using a survey tools. The overall annual morbidity, mortality and case fatality rates have been estimated from the sample as 33.50%, 20.57% and 61.41% respectively. Major causes of morbidity were reproductive diseases (aborted fetus), followed by Classical swine fever and major cause of mortality were also reproductive diseases (aborted fetus) followed by Classical swine fever and respiratory diseases. Aborted fetuses were the major challenges under village condition in study area, so major emphasis should led to attend the reproductive problems. The probability of getting diseases reduces with increase in age.

Acknowledgements

The survey was supported under the research project “ Estimation of economic losses and analysis of morbidity and mortality of important diseses of swine in Mizoram state” funded by the Central Agricultural University (CAU), Imphal, Manipur. The authors express their gratitudes to Dr. M. Premjit Singh, Hon’ble Vice Chancellor, CAU, Imphal, for providing all the necessary support to carry out the study.

References

  1. BAHS 2014. 19th Live Stock Census, Department of Animal Husbandry, Dairying and Fisheries, Ministry of Agriculture available on http://dahd.nic.in.
  2. Basumatary R., Naskar S., Kumaresan A., Khargharia G. And kadivel R.K. 2009. Analysis of mortality pattern among indigenous and upgraded pigs under subtropical hill agro climatic conditions in eastern Himalayas. Livestock Science, 3 (2-3):169-174.
  3. Chaudhary JK, Singh B, Prasad S, Verma MR 2013. Analysis of morbidity and mortality rates in bovine in Himachal Pradesh. Veterinary World, 6: 614-619.
  4. Deka, R., Thorpe, W., Kumar, A., Lapar, M.A. 2008. Assam’s pig sub-sector: current status, constraint and opportunities. International Livestock Research Institute (ILRI), New Delhi.
  5. Mondal S.K., U. K De, G. K. Das, A. M. Powde and A. K. Verma 2012. Pattern of mortality of crossbred pigs in an organized swine production farm. Livestock Sci., 3:37-44.
  6. Nandi, S., Muthuchelvan, D., Ahuja, A., Bisht, S., Chander, V., Pandey, A. B., Singh, R. K., 2011. Prevalence of classical swine fever virus in India: a 6-year study (2004 – 2010). Transboundary and Emerging Diseases, 58:461 – 463.
  7. Palanivel, K.M., Sathivelan, S.M., Gopinathan, A., Sriram S.K., and Kumarasamy, P. 2012. Incidence of Mortality among Swine Due to Classical Swine Fever–Post Mortem FindingsIndian Journal of Animal Research, 46 (1) 86-88.
  8. Prakash Choori, S. S. Patil, D. Rathnamma, R. Sharada, B. M. Chandranaik, S. Isloor, G. B. Manjunath Reddy,S. Geetha and H. Rahman 2015. Prevalence of classical swine fever in Karnataka, India. World, Vol.8:541-544.
  9. Sarma D K, Mishra N, Rajukumar K, Sarma S and Singh N K. 2008a. Isolation and characterization of classical swine fever virus from pigs in Assam. Indian Journal of Animal Sciences. 78: 37-39.
  10. SPSS/PC: Windows for version, 17.0., Release on December 2016. (Microsoft Corp).
  11. Wright, I.A., Deka, R., Thorpe, W., Lapar, M. L. 2010. The pig sector in the northeast India: status, constraints and opportunities. A paper presented at the international symposium “Sustainable Land Use and Rural Development in Mountainous Regions of South East Asia, Hanoi, 21-23 July, 2010.
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