INTRODUCTION

Clinoptilolite (cnlp), a natural zeolite, possess absorption of suitable diametered molecules by losing and gaining water reversibly, and exchange their constituent cations without appearently changing their structure (namely;ion-exchange) ^1,2. Within the development of physical and chemical properties of zeolites, they have been participated to animal nutrition within the last 50 years, mainly for improving animals’ performance ². Dietary addition of cnlp resulted in increased milk production ³. By addition of clnp in colostrum, improvement within the transfer of IgG and reducing neonatal morbidity might be available ^4,5.

One of the concerns that arise from their use as a feed additive is whether their short term supplementation in the animals’ rations has any effect on their total weight gain. Those effects are not expected directly, since its particle size may not be absorbed from the gut ⁶. However it is possible to interfere with weight gain in relation to the property of zeolite having a role as an ammonium reservoir in the alimentary tract, permitting the animal more efficiently using ingested nitrogen ⁷, which all would be thoroughly discussed within the discussion section. Throughout the paper zeolite and clnp would be merely used as synonyms, as clnp is a natural zeolite.

Regarding cattle (mainly beef) industry weaning weight of calves is one of the important traits affecting net income. Calf weaning weight may be influenced by the genetic potential of the calf growth and the amount of milk received from the dam. There is an important correlation between milk yield and weight gain of calves to weaning, for different cattle breed ⁸. Weaning weight is one of the main traits in characterizing cattle. Hence it is important to identify major factors associated with weaning weight. There was little documented information as to the level of association between short term clinoptilolite administration and growth of calves to weaning for Holstein calves. Therefore the aim of this study was to evaluate the relation between short term supplementation at 2 different levels (1 g/kg or 2 g/kg) of clnp within the colostrum of dairy calves and total weight gain/mean daily gain.

MATERIALS AND METHODS

Site of the study and animal population. The study was conducted in a dairy herd with approximately 75-90 calves per year at Aydin municipality [Karahayit village; Latitude in decimal degrees : 37.783333, Longitude in decimal degrees: 28.016667, Latitude in degrees, minutes, and seconds : 37°47’00”N, Longitude in degrees, minutes, and seconds ): 28°01’00”E], located at Aegean part of Turkey. The area has very well and warm geo-climatic conditions. This herd also consisted of 126 head purebred lactating Holstein cows and 57 heifers were totally confined in free-stall housing without access to pasture. To those of 49 Holstein calves, were kept in individual boxes. As the time of parturition approached by the local veterinary surgeon, the pregnant cows were moved to straw-bedded maternity pens. Following parturition, the umbilicus of each calf was treated traditionally with Povidone iodine. Afterwards the neonatal calf was weighed and transferred to an individual pen. Traditionally a total of 2.5 kg of dam’s colostrum was fed via nipple bottle to all neonatal calves within the first 6 h of life, besides colostrum feeding was continued every 12 h for 2 days ⁷.

Grouping and classification of animals. Prior to study necessary ethical guidelines were taken into consideration, and a written owner consent was available for all calves involved. The owner of the farm was also a Veterinary surgeon, who was well informed and given all necessary data for enrollment into the groups. A total of 24 clinically healthy calves without diarrhea were assigned in a subset of three major groups of calves were studied:

Group I (n=8) received colostrum with clnp at the rate of 1 g/kg started immediately following calving at 12 and 24 hours, for a total of 2 doses.

Group II consisted of calves (n=8) receiving colostrum with clnp at the rate of 2 g/kg within the same interval as the first experimental group.

The last group, which served as control, received solely colostrum. Total weight at birth and there after daily weight gain following clinoptilolite administration was deemed on a prior trial ⁷.

Calf weight was recorded at birth and daily until the end of the trial on week 6.

Clinoptilolite material. The clnp material used contained approximately 93% clinoptilolite (Nat min 9000^®, Gordes Zeolit Madencilik, Turkey) with chemical formula [(Na_0.5 K_2.5) (Ca_1.0 Mg_0.5)(Al₆ ,Si₃₀) O₇₂ . 24 H₂O₂]_, as was also used in a prior study involving the vast majority of the present authors ⁹.

Statistical analysis. Statistical analysis of the results was performed by use of SPSS 18.0 for Windows (SPSS, 2009). One way ANOVA was used for statistical analysis of data. The significance of the differences between groups for total weight gain, and mean daily gain was compared by Bonferroni t-test, as was also used in a prior trial ⁷.

RESULTS

Group had significant effect on weight (kg) of Holstein calves [twg (mean±SE)- control: 12.66±0.349, group I: 14.73±0.414, group II: 14.19±0.468, p<0.01; mdwg (mean±SE)- control: 0.338±0.0155, group I: 0.396±0.0189, group II: 0.397±0.0196, p<0.05]. There was a significant difference observed for twg (p<0.01) and mdwg (p<0.05) among control group and both clnp treatment groups. Different clnp (1 g/kg or 2 g/kg) levels did not differ significantly regarding body mass postpartum. Statistical significance of differences between groups were presented in Table 1.

DISCUSSION

Weight gain in relation to zeolite additive might be briefly explained within the property of zeolite having a role as an ammonium reservoir in the alimentary tract. The latter may permit the animal more efficiently using ingested nitrogen ⁷. From another point of view, zeolite might improve the general health status of calves, and probably stimulate disease resistance ¹⁰. Zeolite (i.e. containing NH₄ ⁺), such as clnp, might hasten growth of nitrogen loving bacteria contributing to the health of animals ⁷, as aforementioned above. Besides zeolite could take up harmful heavy metals, or alternatively might regulate pH in the gut, resulting in less stomach ailments ⁷. One other possible mechanism related to increased weight gain might possibly involves zeolite (clnp) supplementation accompany better milk protein digestion and higher amino acid absorption ⁷. These all may contribute to increased daily weight gain for calves, as in agreement with the purpose of the present study. Consequently in this study group had significant effect on weight (kg) of Holstein calves [twg (mean±SE)- control: 12.66±0.349, group I: 14.73±0.414, group II: 14.19±0.468, p<0.01; mdwg (mean±SE)- control: 0.338±0.0155, group I: 0.396±0.0189, group II: 0.397±0.0196, p<0.05]. There was a significant difference observed for twg (p<0.01) and mdwg (p<0.05) among control group and both clnp treatment groups, in which influenced weight.

The addition of zeolite at 2 different levels (1.2 or 3%) within the colostrum or milk for 15 days improved health status and disease resistence in calves ¹⁰. In the present study although clnp administration possessed a better weight gain, different clnp (1 or 2 g/kg) levels did not differ significantly regarding body mass postpartum. Zarcule et al ¹¹ indicated that on 45 days of calving, body mass of calves receiving colostrum with 5 g/L (group I) and 20 g/L clnp, were higher in contrast to control group. However in that study on 90 days after parturition, there was no difference among body mass in groups. Furthermore Step et al ¹² reported 0.5 or 2% clnp addition did not influence body mass or avarage daily gain among groups.

In a prior study on sheep, the influence of natural zeolite on the production of fattening lambs were investigated. That trial composed of two groups of lambs (n=15 in each) as the control and experimental groups. The test group of animals were given a mixture of zeolite fed from birth till their 14th day of life. Afterwards another rich zeolite compound was given beginning from their 15th day of life along with the feed mixture. The average weight of lambs at the end of the experiment, in accordance with the sequence of treatments in control: experimental groups was 24.40:26.94 kg, respectively (p<0.01). Daily weight gain of lambs, during the trial, was 229:256 g in control: experimental groups, respectively and in the experimental group there was a difference of 27g (11.79%) elevation (p<0.01) ¹³. The experimental group of lambs presented a better utilization of protein, dry matter and energy ¹³. As was also afroementioned above this might be the case fort he present study, in which milk protein might be better utilized by clnp administration.

The role of zeolite or clnp for retaining ions such as ammonium has to be briefly discussed. Zeolites appear to have a role as a buffer within the cow’s digestive system, via storage of nitrogen as ammonium and gradual release by ion exchange through potassium and sodium. Therefore cows receive major benefit from the same quantity of ration ¹⁴ In addition rumen ammonia was decreased via zeolite addition ¹⁵. However this was not the condition in the present study. Retention of ammonium is not an important factor because the newborn calf (involved also in this study) works digestively as a monogastric animal. Thus the ruminal microflora has no ammonia to be used because it has not been developed.

In conclusion short term supplementation of clnp in colostrum could significantly affected twg and mdwg in neonatal dairy calves. Since our results were in accordance or in contrast to some of limited studies aforementioned above, it seems further investigations elucidating effects of clnp with varying amounts and duration of supplementation on weight gain might be useful.