Experimental study on the effect of in-feed administration of a clinoptilolite-rich tuff on certain biochemical and hematological parameters of growing and fattening pigs

The effect of the long-term dietary use of a clinoptilolite-rich tuff (Cp) on certain biochemical and hematological parameters was studied in pigs. Forty-eight healthy piglets (24 females and 24 males) were used in the study, equally allocated in two experimental groups, depending on the inclusion or not of Cp in their feed (Cp+ and Cp- groups respectively). Cp was incorporated in their feed at the inclusion rate of 2% and was administered continuously from weaning to slaughter. All pigs were individually weighed upon commencement of the study [25(+/- 3) days of age] and subsequently at the end of the weaning, growing and fattening stages [70(+/- 3), 112(+/- 3) and 161(+/- 3) days of age, respectively] and blood sample collections were performed for analyses. Cp ingestion was well tolerated and resulted in a higher body weight gain during the weaning stage, as well as during the whole monitoring period (P<0.05). The diet had no effect on serum K, Na, Ca, P, total protein, albumin and total bilirubin concentrations throughout the study (P>0.05). Furthermore, no significant alteration was noticed concerning the hematocrit, leucocyte count and hemoglobin concentration (P>0.05). Conversely, the dietary inclusion of Cp resulted in a lower serum urea-N and cholesterol concentrations in all blood samplings apart from the initial one (P<0.05). Likewise, Cp+ group demonstrated an elevated serum glucose concentration at the blood samplings performed on 112(+/- 3) and 161(+/- 13) days of age and a lower AST activity at the latter (P<0.05). In the context of this study, the long-term dietary use of Cp at the inclusion rate of 2% appeared to enhance the performance of growing and fattening pigs without adversely affecting their health status in terms of undesirable changes of their biochemical and hematological profiles. (C) 2007 Elsevier B.V. All rights reserved.