Sepiolite is a hydrated magnesium silicate clay with binder properties. The effect of a sepiolite product on pellet durability of diets varying in particle or fat addition was studied in two experiments. In the first experiment, a 2 X 3 factorial arrangement with two particle sizes (3 and 6 mm) and three sepiolite product levels (0, 10 and 20 g kg(-1)) was designed. Four samples of feed pellets were obtained from each combination of factors in order to measure durability using the Pfost durability tester. Temperatures at two points of the pelleting process, pellet production (kg h(-1)), and percentage of fines in the cooler were measured. Durability of pellets varied between 81.5 and 91.0, Durability of pellets increased with the low particle size accounting for 79.3% of the total variability (P < 0.001). The sepiolite product improved durability, independently of particle size (P < 0.001) accounting for 20.5% of the total variability. The sepiolite product increased the temperature of pellets at the outlet of die (P < 0.01).In the second experiment the effect of sepiolite in starter and finisher chicken diets was investigated using three sepiolite product levels (0, 10 and 20 g kg(-1)). Four samples of feed pellets were obtained from each treatment in order to measure durability using the Pfost durability tester. Temperatures at two points of the pelleting process and percentage of fines in the cooler were measured. The sepiolite product improved the durability of pellets of starter chicken diets (P < 0.05) but not in the finisher diets (P > 0.05). The response in the starter diet was dose dependent. Temperature of pellets at the exit of die increased by the addition of the sepiolite product in the starter diets only (P < 0.10).

Sepiolite is a hydrated magnesium silicate clay with binder properties. The effect of sepiolite on pellet durability was studied using feeds varying in the level of fat and fibre. A 2 × 2 × 3 factorial arrangement was designed with two levels of sepiolite (0 and 20 g kg−1), two levels of added fat (5 and 40 g kg−1) and three levels of fibre (40, 70 and 140 g kg−1). Four samples of feed pellets were obtained from each combination of factors in order to measure durability using the Pfost durability tester. Temperatures at three points of the pelleting process, and percentage of broken pellets and of fines in the cooler and cyclone were measured. Durability of pellets varied between 81.9% and 98.0%. Results of durability indicated that fat accounted for 45% of the total variability, sepiolite for 19.2% and fibre for 15.5%. There was a significant interaction (P < 0.001) between sepiolite and fat, indicating that sepiolite's effect was more pronounced when the fat level was high. Thus, durability of the pellets at a level of 5 g kg−1 was 95.8% without sepiolite and 96.8% with sepiolite. At a fat level of 40 g kg−1, durability was 86.5% without sepiolite and 93.6% with sepiolite. The interactions between fibre and sepiolite, and between fibre and fat were less important and accounted for only 4% of the variation. Percentages of broken pellets and of fines in the cooler and cyclone were reduced by sepiolite addition.

An experiment was conducted to determine the response of growing Japanese quail to two dietary energy levels, high (3,200 kcal ME/kg) versus low (3,000 kcal ME/kg), and two forms of presentation, mash versus pellet. Seven thousand, two hundred day-old Japanese quail (Coturnix coturnix japonica) were randomly distributed into 24 floor pens containing 300 quail each. The experiment was divided in two phases: starter (until 2 wk of age) and finisher (Days 14 to 33). Weight gain was less (P < .05) for quail fed the low-energy mash diet than for those on other treatments. Feed consumption increased (P < .001) when low-energy and mash diets were fed. Metabolizable energy consumption was greater with the mash diets. Feed conversion improved (P < .001) when high-energy and pelleted diets were fed as compared with low-energy and mash diets, respectively. Results indicated that daily gain and feed conversion of quail fed the low-energy, pelleted diet equaled those of quail fed the high-energy mash diet. Pelleting improved the caloric efficiency of gain by quail. Quail seemed to adjust caloric intake according to the energy level of the diet.

The purpose of the present work was to compare the bioavailability of structural fluorine contained in sepiolite and in sodium fluoride for laying hens. Three hundred 27-wk-old laying hens were fed one of three diets: 1) a control based on corn, barley, and soybean meal containing 21 mg/kg of fluorine; 2) a sepiolite diet in which 2% sepiolite replaced 2% barley in the control diet and which contained 217 mg/kg of fluorine; and 3) a NaF diet, consisting of the same control diet to which NaF was added to contain 217 mg/kg of fluorine (the same level of F- as the sepiolite diet). The experiment ended when hens were 64 wk old. Fluorine concentration in the tibial bone of hens fed the NaF diet was four times higher than in the control, and twice as high in eggshell. In contrast, hens fed sepiolite had fluorine concentrations in tibial bone and eggshell not significantly higher than fluorine concentrations in the controls. These results indicate that fluorine from sepiolite was not available. The effects of the different diets on egg production, feed intake, feed conversion, egg weight, shell and interior egg quality, dry matter of feces, and body weight gain were also determined but no significant differences due to the dietary treatment were observed.