346 AJVR, Vol 70, No. 3, March 2009 U se of natural and synthetic zeolites in farm animal nutrition is increasing, mainly with the aim of im- proving performance and protecting against mycotoxin intoxication. 1–3 Zeolites have unique properties such as the ability to lose and gain water reversibly, to adsorb molecules of a certain diameter (adsorption property) or act as molecular sieves, and to exchange their con- stituent cations without major change of their structure (ion-exchange property). 4,5 These properties make zeo- lites useful in animal nutrition. Because of the potential adsorbent and binding ef- fects of zeolites, one of the major concerns that arise from their use as feed additives is whether long-term Effect of long-term dietary supplementation with clinoptilolite on performance and selected serum biochemical values in dairy goats Panagiotis D. Katsoulos, DVM, PhD; Sotirios Zarogiannis, PhD; Nikolaos Roubies, PhD; Georgios Christodoulopoulos, DVM, PhD Objective—To determine the effect of dietary supplementation with clinoptilolite on health and production as well as serum concentrations of fat-soluble vitamins, macroelements and trace elements, and activities of hepatic enzymes in dairy goats. Animals—72 Saanen-cross dairy goats. Procedures—Goats were randomly assigned to 1 of 2 groups. The clinoptilolite group (n = 36) received concentrate feed, of which 2.5% contained clinoptilolite; the control group (36) received unsupplemented feed. The experiment began 8 weeks before parturition and continued to the beginning of the next nonlactating period (280 days of lactation). At the day of parturition, kids were weighed. Milk yields were recorded at day 60 of lactation and thereafter at monthly intervals. Milk percentages of fat, protein, and lactose and somatic cell count (SCC) were evaluated at the same points. Blood samples were obtained at the beginning of the experiment, the day of parturition, and thereafter at monthly intervals to measure serum concentrations of fat-soluble vitamins, macroelements and trace elements, and activities of hepatic enzymes. Results—Birth weights of triplets and quadruplets were significantly higher in clinoptilo- lite-treated goats versus control goats. Milk fat percentage was significantly higher and SCC was significantly lower in clinoptilolite-treated goats, compared with respective val- ues in control goats. However, no changes in serum concentrations of any variable were detected. Conclusions and Clinical Relevance—In the context of this experiment, clinoptilolite supplementation of concentrate feed at 2.5% improved milk fat percentage in dairy goats, without adverse effects on the serum variables evaluated. Furthermore, the reduction of SCC achieved with clinoptilolite supplementation provided some evidence of improved milk hygiene. (Am J Vet Res 2009;70:346–352) supplementation in ruminant rations affects an animal’s physiologic status with respect to amounts of essential nutrients such as vitamins and minerals. If a consider- able amount of essential nutrients is rendered unavail- able to the animals via feed, the consequent nutritional imbalances might have undesirable effects on perfor- mance and health status. There is a lack of experimen- tal data regarding the effects of long-term feeding of clinoptilolite, a natural zeolite, to small ruminants, par- ticularly goats, on their health and milk production. In dairy cattle, long-term administration of clino- ptilolite is associated with a significant increase in milk yield 6,7 and milk fat percentage, 8 without adverse effects on serum concentrations of fat-soluble vitamins 9 and of certain trace minerals 10 or macroelements. 11 Further- Received May 24, 2008. Accepted July 14, 2008. From the Clinic of Medicine, School of Veterinary Medicine, Uni- versity of Thessaly, 431 00 Karditsa, Greece (Katsoulos, Christo- doulopoulos); the Department of Physiology, School of Medicine, University of Thessaly, 411 10 Larissa, Greece (Zarogiannis); and the Laboratory of Clinical Diagnosis and Clinical Pathology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece (Roubies). Address correspondence to Dr. Katsoulos. ABBREVIATIONS AST Aspartate aminotransferase BHBA β-Hydroxybutyrate GGT γ-Glutamyltransferase SCC Somatic cell count Unauthenticated | Downloaded 08/18/22 08:04 AM UTC