02317naa a2200241 a 450000100080000000500110000800800410001910000200006024501250008026000090020552015760021465300310179065300110182165300200183265300120185270000140186470000190187870000190189770000230191670000170193970000160195677301030197215308042016-06-24       2000    bl uuuu     u00u1 u    #d1 aCIARLINI, P. C.  aSerum pepsinogen concentration in Suffolk and polwarth ewes at the end of gestation, during lactation and after weaning.  c2000  aThe relationship between eggs per gram of feces (EPG) and serum pepsinogen level was studied in Polwarth and Suffolk ovine breeds. They were naturally infected by gastrointestinal nematodes and were studied at the end of gestation, during lactation and after weaning. ln this study, twenty sheep (10 Suffolk and 10 Polwarth) between three and four years old, raised together paddocks on a rotational system, were used. All sheep were treated with Closantel Ò (10 mg/kg) thirty days before parturition. The serum pepsinogen and the EPG were determined in the second and first week before parturition as well as in the second, fourth and sixth week of lactation and in the first and second week after weaning. The highest percentages of larval in the fecal cultures were Haemonchus. A periparturient rise in EPG were observed in both breeds, Suffolk and Polwarth. The EPG had a huge increase near parturition and kept high during lactation, however, without a significant increase of the serum pepsinogen level. After weaning, the EPG showed a continuous decrease associated with an increase in the serum pepsinogen. There was no significant correlation (p &gt 0,05) between the EPG and the serum pepsinogen in Suffolk breed, whereas there was a strong negative correlation (r = -0,76; p &lt 0,0001) in Polwarth sheep, but only after weaning. The results suggest that the increase in serum pepsinogen, after weaning, is related with a more efficient immune response of the hosts against the nematode infection, after the end of the periparturient relaxation of resistance.  aNematóide gastrintestinal  aOvinos  aPepsina sérica  aSuffolk1 aMOTTA, T.1 aKOHAYAGAWA, A.1 aALENCAR, N. X.1 aAMARANTE, A. F. T.1 aLOPES, R. S.1 aLENZ, F. F.  tRevista Brasileira de Parasitologia Veterinária, Rio de Janeirogv. 9, n. 1, fev. p. 17-21, 2000.