EFFECTS OF CONCENTRATED FEED ENRICHED WITH ZEOLITE AND GLYCERIN ON PRODUCTIVITY OF BEEF CATTLE

Sixteen native breeds of cattle (n=16) were selected as experimental animal and divided into two control and two experimental group. The cattle for this study were two months old native breeds that all castrated males with average live weight 270±5 kg. During the experimental period cattle in first control group were grazed on open pasture, while second control group were kept in door and fed by well-balanced concentrated feed for beef cattle. However first experimental group were fed by feed ration enriched with 2% of native zeolite, whereas second experimental group was provided by ration with 2 % of zeolite and 6 % of glycerin. All of these cattle in two different groups were fed for 52 days in total, which divided into preparation and experimental periods of 7 and 45 days. Daily body weight of cattle in first control group was declined by 15 kg (357.5g) while it was increased by 22.25 kg (530g) in second control, 30.04 kg (714.5 g) in first experimental and 24.75 kg (589.3 g) in second experimental groups (p<0.001).


INTRODUCTION
The Mongolian herds well adapted to the extreme climate and survived during winter and spring via losing weight obtained in summer and autumn. Winter and spring feed availability on the pastures decreases by 60-70%, nutritive value of pasture plants declines by 50-60% and grazing time of animals is shortening by 4-6 hours. Therefore, Mongolian livestock losses their weight up to 25-30% of summer weight if not supplementary feeing [5]. Mongolia rises 4.04 million of head cattle which accounts 6.63% in total number of livestock in 2017. The success of any animal production depends on proper nutrition and feeding program. The key to a good feeding program for beef cattle is to have the animals gaining weights at the proper rate to reach target weight and condition at show time. There is concentrated feed for beef cattle, produced by Altan taria company, which is enriched with minerals however there is no evidence that adding zeolite, glycerin and their mixture to beef cattle feed in Mongolia.
Glycerin consistently decreases acetate:propionate ratio, and may have inhibitory effects on fibre digestion, which is mediated via its inhibitory effects on some microbial populations. Concentrations less than 10 percent of the diet dry matter yield favourable biological responses in cattle, whereas levels in excess of 10 percent may have deleterious consequences for feed intake and growth of cattle [28]. Also zeolite given to piglets as a feed additive (2%) since weaning and throughout the fattening period caused a significant increase in weight gain and a noticeable increase in feed conversion [4]. The aim of this study was to investigate the effect of concentrated feed for beef cattle enriched with glycerin and zeolite source on feed intake, weight gain performance.

MATERIALS AND METHODS
Compound feed for beef cattle was produced at Bayalag-Emeelt feed processing factory located in Khan-Uul district of the Ulaanbaatar and feeding trial was conducted in November 2014 Bayan Simmental beef farm situated in Bayan sum (43º34'15''N, 104º25'33''E) of Tuv province. Two years old, sixteen Mongolian native cattle with live weight approximately 250 kg were selected and divided into two control and two experimental groups. Selected cattle were fed by experimental feed for preparation and experimental periods. The experimental feed was applied to cattle four times a day (twice in the morning and afternoon, respectively) and animal had free access to pure water during the experimental period. Feed was placed in feeding pots and applied to each cattle individually. Experimental feed was formulated from mixtures of concentrated feed and natural hay grass. These feed mixtures varied differently along the feeding experimental periods. At first period the feed were comprised ratio of 70:30 percentage of concentrated feed and hay, respectively while it was 60:40% at middle. Moreover at last period, it was balanced by 50:50 percentage of above mentioned two main feed ingredients. Chemical composition of these feed were used for the experiment is shown at the table 1. Feed intake, body weight and daily gain, slaughter yield of experimental cattle was determined. The average daily gain (ADG) obtained was calculated as follows: Where FLW is the final live weight and ILW is the initial live weight of each period.
Crude protein was determined using Kjeldahl procedure (АОАС 988.05), total fiber content in an ANKOM 200 fiber analyzer (АОАС 962.09) and dry matter, organic matter concentrations by drying sample material at 105°C as well as total ash content by incinerating at 550°C (АОАС 942.05) in Animal feed evaluation laboratory of School of Animal Science and Biotechnology, Mongolian University of Live Science. Organic matter digestibility and metabolizable energy were calculated by fiber index method formulated by Gendaram [6]. The statistical data analysis was performed in SPSS version 16.0 for Windows (IBM Corp., 2011) with a two-tailed significance level of p≤0.05.

RESULTS
The crude protein, fat and crude ash in concentrated feed enriched by natural zeolite was increased by 2, 0.03 and 4.3%, respectively while organic matter, total fiber and ether extracts were decreased by 4.3, 1.3 and 5.2%, respectively. Generally, crude protein, fat and total ash contents of the concentrated feed enriched with natural zeolite and glycerin was increased whereas the fiber content was declined.  From the table 3, hay intake of experimental feed was 41-43% in all groups (P>0.05) during the initial stage of treatment. Hay intakes of different feed in three groups were significantly increased from initial to final and the highest intakes were found at the final stage of experiment. The growth and meat productivity: The absolute and relative growth and daily weight gain are the most relevant indicators to measure meat production.  Table 5. Daily weight gains and growth of beef cattle ***: p˂0.001 **: p˂0.01 *:p˂0.05 ns: no significant Negative relative growth was found among beef cattle kept in first control group whereas weight gain observed in other tree groups. However, improvements of relative growth in these three groups were similar; the highest growth was occurred in first experimental group.  Table 5. Daily weight gains and growth of beef cattle ***: p˂0.001 **: p˂0.01 *:p˂0.05 ns: no significant Negative relative growth was found among beef cattle kept in first control group whereas weight gain observed in other tree groups. However, improvements of relative growth in these three groups were similar; the highest growth was occurred in first experimental group. .52 kg in first and second controls, first and second experimental groups. In other word, slaughter yields were 48.2%, 50.9%, and 53%, 50.9% in first, second control and first, second experimental groups. The feed applied to beef cattle kept in first experimental group showed the highest positive effects on slaughter weight and slaughter yield (p<0.001). The lowest once were found in first control group.

DISCUSSION
Chemical composition and nutrient value of beef cattle: Tsedev [19], Otgoo [12], Asuren and Sanchir [1], Gendaram and Togtokhbayar [6], Byambasaikhan and Rinchindorj [15], Gurbazar [4] and Rentsenkhand [16] were conducted studies on concentrated feed for different types of animals in Mongolia. The crude protein, crude fat and extract ether contents of diet used in present study was higher by 0.8%, 3.7% and 0.3% in comparison to composition of concentrated feed consisted from 34% bran, 14% wheat, 10% barley, 10% oat, 30% straw and 2% salt by Tsedev [19]. Organic matter digestibility and metabolizable energy of enriched concentrated feed used present study was higher by 15.4% and 0.2 MJ than findings by Tsedev [19]. These parameters were higher by 16.2% and 0.3 MJ comparing results from Rentsenkhand [16]. These inconsistences can be explained by balancing metabolizable energy of concentrated feed in enriching with protein and minerals. Growth and meat productivity of beef cattle: Studies on different feeding and management options for beef cattle in Mongolia were conducted by Javzmaa [8] in crossbred of native Mongolian and Kazakian white head breed, by Tserendulam [19] and Gonchig [3] in Simmental heifer, by Tsedev [19], Gombodorj [2] in crossbred of Mongolian native with Kazakian white head breed, Nergui [10], in growing calves of Kazakian white head and Selenge breeds, by Rinchindorj [14] and Tumenbayar [18] in Selenge breed, by Dorjbat [7] in Mongolian breed of cattle.
An addition of natural zeolite to feed ration has resulted on digestibility of various nutrients and metabolic function of the animal. The zeolite added by 3, 5 and 8% into total ratio's dry matter has increased digestibility of nutrients by 1.27-6.33%, daily body gain by 15.22-23.48%, although feed intake was declined by 14.86-19.57 as reported by Renchindorj and he suggested that 5% zeolite addition to feed ratio has the highest result to increase feed efficiency [27]. Found that up to 18% of glycerin addition to feed ratio showed improvement in feed efficiency and energy supplement [26]. When glycerin added to feed by 4, 8 and 12% of total feed ration, live weight of beef in feedlot was increased by 125 kg after 90 days and 12% of glycerin addition showed no negative effects on rumen fermentation, metabolism and meat quality [22]. Daily weight gain in present study was higher by 165.5 g, 163.3 g, 8.5 g, 105.9 g and 108.4 g than results determined by Dorjbat [7], Javzmaa [8], Tserendulam [21], Gombodorj [2] and Rinchindorj [14]. Nevertheless, daily weight gain resulted by Tumenbayar was higher by 63.5 g that finding by us. These differences in growth were most probably due to productivity of breeds. Slaughter yield of beef cattle in this study was greater than these measured by Tumenbayar [18], Dorjbat [7], Gombodorj [2] and Gonchig [3]. This result may be obtained due to feed enrichment by zeolite and glycerin. There is big potential to increase meat production of growing cattle when feed them well balanced feed ration.

CONCLUSIONS
• Cattle kept in door and fed by experimental feed gained while grazing cattle lost their body weight by 15 kg • Natural zeolite and glycerin addition to growing beef has significance not only to supply mineral requirement of cattle, improve efficiency of nutrients of the feed also improve digestibility of nutrients and increase meat production. Therefore, our results suggest that 2% zeolite and 6% glycerin addition to total dry weight of the feed is most suitable.