Plasma biochemical indices at various stages of infection with a field isolate of Eimeria tenella in broiler chicken

Coccidiosis has a major impact on poultry industry as it affects broiler and layer birds of all age groups. Caecal coccidiosis, caused by is a very devastating enteric disease in broiler,which involves huge economic loss experimental infective dose of in broiler th th chicken and subsequent alterations in different plasma biochemical constituents were evaluated at interval of 5 , 7 and th 9 day of post inoculation (PI) with the selected dose of 20000-25000 sporulated oocyst per bird. The dose was selected based on titration. A significant increase in plasma glucose, total cholesterol level and aspartate aminotransferase (AST) activity were observed where as a significant decrease in the level of total plasma protein, albumin, globulin, triglyceride and alanine aminotransferase (ALT) activity were evident during infection


Introduction
A little information is available on infection pattern in broiler chicken and its Poultry industry is one of the rapidly growing subsequent effect on plasma biochemical constituents.major segments of agriculture sector and has been Therefore, showing a tremendous growth in India during the last to determine experimental few decades.But various diseases have also come into infective dose of the particular isolate in broiler the way of growth.Coccidiosis, an enteric parasitic chicken and plasma biochemical alterations at various disease caused by protozoan parasite of various stages of infection with the selected dose of innoculum.species under the genus Eimeria, is one of the most common and expensive diseases in the poultry Materials and Methods industry (Shirley et al., 2007).It has a major economic Animal housing and management: Day old broiler impact on both growers and broiler poultry industry chickens (Vencob-100) were procured from Hi-breed worldwide (Pinard-van der Laan et al., 2009).It is International, Kolkata and kept in deep litter system responsible for 6-10% mortality in broiler chicken and coccidian free environment.Birds were provided and huge global economic loss due to impaired feed with ad libitum drinking water and feed free from antith conversion, retarded growth (Tipu et al., 2002), coccidial drugs.On 5 day birds were vaccinated additional cost of medication and deterioration of the against Ranikhet Disease.meat quality (Aliyeva, 1999;Ahmedov et al., 2006).Experimental design: Two trials were conducted Severity of this disease is dependent on type of isolate, separately.Trial-1 for determining the infective dose site of predilection of Eimeria tenella causing 80-90% morbidity with 10-20% mortality and Trial-2 for studying the changes in different plasma biochemical constituents at various stages of infection.

1999)
Collection and sporulation of oocysts: Oocysts, sub-clinical form of infection.
Present study was conducted with a field isolate of Eimeria tenella of the parasite as well as dose of oocyst inoculum.Eimeria tenella, one of the most pathogenic species that parasitizes growing chickens and causes considerable financial loss to the poultry industry (Williams et al., through  For infective dose determination eighty-four using 2, 4-Di-Nitro-Phenyl-Hydrazine through formation of coloured hydrazone complex in presence unsexed day old broiler birds were randomly divided of sodium hydroxide.into 6 groups of 14 each.Two birds from each group were sacrificed and examined to confirm the absence Statistical analysis: Data were partitioned and th of any parasitic stage of Eimeria tenella at 7 day of subjected to statistical analysis by Student t-test and significance at 5% (P<0.05) and 1% (P<0.01)level age.On the same day, five different doses (5000-6000, were tested by Duncan Method (Snedecor and 10000-12000, 20000-25000, 50000-55000 and Cochran, 1967).95000-100000) of oocysts were inoculated to each group by crop inoculation keeping one group as

Results
healthy control.Infective dose was determined on 6-7 day post inoculation by clinical symptoms and caecal Infective dose for the experiment: From Trial-1 lesion scoring.(Johnson and Reid, 1970).
the infective dose for caecal coccidiosis with Trial-2: sporulated oocyst was determined based on significant Twenty-eight unsexed day old broilers chicks symptoms of droopiness, huddling, anorexia, were randomly divided into two groups of 14 each.At th emaciation, bloody dysentery in live birds and caecal 7 day of their age two birds from each group were score lesions in dead birds as well birds sacrificed at sacrificed to confirm the absence of any parasitic stage the end of trial-1.The infective dose of Eimeria tenella of Eimeria tenella and one group was inoculated with oocyst for the trial was considered as 20000-25000 of 20000-25000 of sporulated oocyst by crop inoculation sporulated oocysts per bird ( group on 5 , 7 and 9 day post inoculation.Plasma glucose and total plasma protein: Trial -2 Sample collection and storage: Blood samples revealed a significant (P<0.05)variation in blood were collected in heparinized vials and immediately glucose level between healthy control and infected centrifuged to separate plasma.Separated plasma was th th 0 group on 5 day, 9 day and a highly significant stored at -20 C for biochemical analysis.th (P<0.01)variation on 7 day of PI.In infected group, a Plasma biochemical indices: Plasma glucose was th significant (P<0.05)variation was observed on 7 day estimated by Glucose Oxidase Method (Trinder, 1969) th th when compared to 5 day and 9 day of PI (Figure -1).using 4-amino phenazone as oxygen receptor.
Hypopreoteinemia in infected group with highly Total plasma protein and plasma albumin of the significant (P<0.01)variation from healthy group was samples were determined following Biuret Method th th th evident on 5 , 7 and 9 day PI.Although a highly (Reinfold,1953)  was calculated based on total plasma protein and (P>0.05)variation was noted between 5 and 9 day PI in the infected group (Figure -2).plasma albumin value.
Plasma albumin and globulin: Plasma albumin Automated enzyme method (Fletcher, 1968) was used level showed a highly significant (P<0.01)variation variation (fall/rise) in the same was observed in th th th infected group on different days of PI. between healthy and infected group on 5 , 7 and 9 day PI but no variation was observed in infected group Plasma AST and ALT activity: A highly significant (P<0.01)rise in plasma AST activity in infected group on various days PI .
was observed compared to healthy control group on A highly significant (P<0.01)variation in th th different days PI but no significant (P>0.05)variation plasma globulin level was evident on 5 and 7 day PI th was observed in infected group on different days (5 , between healthy and infected group but without any th th th 7 and 9 ) PI(Figure -7).observable variation on 9 day PI.A significant th Highly significant (P<0.01)fall in plasma ALT (P<0.05)variation in infected group was noted on 7 th th activity in infected group on different day PI was noted day PI compared to 5 and 9 day PI (Figure -4).
compared to healthy control group but with no Plasma triglyceride and cholesterol: A highly significant (P>0.05)variation in infected group on significant (P<0.01)fall in plasma tri-glyceride Coccidiosis is caused by the development and (5 , 7 and 9 ) of PI but no significant (P>0.05)multiplication of coccidia oocyst in the epithelial cells because of interference with phosphorylative of the intestine.Positive correlations exist between carbohydrate dissimilation by an unidentified factor number of oocysts inoculated and degree of infection present in caecum of poultry as suggested by Daugherty in poultry birds.With the increase in inoculum titre, and Herrick (1952).These results corroborate with the pathognomonic lesion score increases along with findings of Kumar and Rawat (1975).Highest level of percentage of sick and dead birds.Table-1 showed that blood glucose on day 7 PI and gradual fall in following low dose of oocyst caused a morbidity of around 50%, days suggests highest degree of stress due to where as higher dose led to more than 80% morbidity maximum infection load on day 7 PI, after which with a high death percentage.Due to inoculation of birds passes through recovery phase as confirmed by higher number of sporulated oocysts, gut system the PM lesion.Low feed intake during acute infective succumbs to infection being unable to fight against the stage may lead to secretion of adrenal cortisones/ high parasitic load.corticosteroids promoting glycogenolysis.(Patra et The significant rise in plasma glucose level may al., 2010).be due to increased glycogenolysis caused by stress Fall in total plasma protein (hypo-proteinemia) induced release of adreno-corticoid leading to in the coccidia infected birds might be due to acute hyperglycemia or disturbed carbohydrate metabolism stress that leads to cortisol secretion and catabolism of  protein (Kaneko et al., 1997).Acute hemorrhage on Veterinary Research Isnstitute, Eastern Regional day 7 PI causes large loss of plasma protein followed Station, Kolkata.West Bengal, India for providing all by rapid movement of interstitial fluid without protein the facilities.into the plasma compartment to induce acute hypo-

Figure- 1 .
Figure-1.Plasma glucose and Figure-2.Plasma total protein level in healthy and infected birds on different days of Post infection.Different superscripts (a,b,c) denote that mean values differ significantly as compared to healthy control group at the period of observation and # denotes significant difference within infected group between different periods of observation.

Figure- 3 .
Figure-3.Plasma Albumin and Figure-4.Plasma Globulin level in healthy and infected birds on different days of Post infection.Different superscripts (a,b,c) denote that mean values differ significantly as compared to healthy control group at the period of observation and * denotes significant difference within infected group between different periods of observation.

Figure- 5 .
Figure-5.Plasma Triglyceride and Figure-6.Plasma Cholesterol level in healthy and infected birds on different days of Post infection.Different superscripts (a,b,c) denote that mean values differ significantly as compared to healthy control group at the period of observation.

Figure- 7 .
Figure-7.Plasma AST and Figure-8.Plasma ALT level in healthy and infected birds on different days of Post infection.Different superscripts (a,b,c) denote that mean values differ significantly as compared to healthy control group at the period of observation.