Indian Journal of Animal Research

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Research Article

Indian Journal of Animal Research, volume 55 issue 2 (february 2021) : 174-179

Influence of Customized Supplement on Voluntary Feed Intake and Nutrient Metabolism in Crossbred Calves

Sandeep K. Chaudhary1, Narayan Dutta1,*, S.E. Jadhav1, A.K. Pattanaik1
1Centre of Advanced Studies in Animal Nutrition Indian Veterinary Research Institute, Izatnagar-243 122, India.
Cite article:- Chaudhary K. Sandeep, Dutta Narayan, Jadhav S.E., Pattanaik A.K. (2020). Influence of Customized Supplement on Voluntary Feed Intake and Nutrient Metabolism in Crossbred Calves . Indian Journal of Animal Research. 55(2): 174-179. doi: 10.18805/ijar.B-3933.

ABSTRACT

The present study was carried out to ascertain the effect of dietary inclusion of a customised supplement to farmers’ based diet on voluntary feed intake and nutrient metabolism in crossbred calves. In order to carry out the experiment, fifteen crossbred calves (18 months old; 166.53±4.93 kg mean BW) were randomly allocated to 3 groups (5 calves in each group) as CON, Treat and SBR, in a CRD for 30 days. The calves in CON (control) group were fed on cereal straw based diet with concentrate mixture as per the farmers’ practices, whereas, the calves in Treat were fed according to CON with additional customized supplement @ 0.25% of BW. The calves in SBR group were fed standard diet as per Kearl (1982). The intake (gd-1) of DM and OM was significantly (P<0.01) higher in SBR than Treat and CON groups, while DM and OM intake as % of BW in Treat group has an intermediate position between SBR and CON groups. The concentrate intake (gd-1) was significantly (P<0.001) higher in SBR followed by Treat and CON group, respectively. However, intake of wheat straw and green maize was found to be identical (P>0.05) among all the groups. The digestibility coefficient of DM, OM, CP, NDF and ADF was significantly (P<0.05) higher in Treat and SBR groups than CON. The N-retention as per cent of intake and absorbed-N was significantly (P<0.001) higher in Treat and SBR groups than CON. The Ca and P retention (gd-1) was significantly (P<0.001) higher in SBR group followed by Treat and CON groups. The intake (gd-1) and density (%) of DCP and TDN were significantly (P<0.001) higher in SBR group followed by Treat and CON groups. Thus, it can be concluded that supplementation of the customised supplement (@ 0.25% of BW) to CON diet significantly improved the voluntary feed intake and nutrient metabolism in crossbred calves. 

INTRODUCTION

Currently, the Indian livestock farming is facing many challenges including shortage of good quality fodder, deficient and disproportionate feeding practices (Sagar et al., 2013; Hegde 2019). This is because of the fact that the animals are being fed on crop residues based rations or grazing without access to balanced energy, protein and mineral supplements which is severely affecting their production and reproduction performance. Furthermore, the availability of nutrients depends on feeds and fodder consumed by animals which is again affected by season, cropping pattern and land holding capacity etc of farmers. (Patel et al., 2007). Dietary energy and protein sources are the most common nutrients limiting the rumen fermentation and microbial protein production, affecting the overall performance of the animals (Seo et al., 2013; Uddin et al., 2015). Concentrate supplementation with easily fermentable carbohydrates and nitrogen source to poor quality roughages can efficiently modulate the activity of rumen microbial ecosystem (Wang et al., 2019). Along with energy and protein, minerals are also important nutritional component having key role in health, production and reproduction of animals (Soetan et al., 2010). Deficiency of the minerals pertains to specific area and is largely influenced by its concentration and level in the feeds as well as fodders fed to the animals. Supplementation with mineral mixture has been proved several times to improve the reproductive and productive performance of dairy animals (Mahanta et al., 2011; Yengkhom et al., 2018). To overcome these problems, a customised supplement was developed which is rich in energy, protein as well as macro and micro minerals. The purpose of developing such customised supplement is to prevent and alleviate the specific nutrient deficiencies and production losses that commonly occur in dairy animals under field conditions due to consistent feeding of poor-quality roughages. Keeping this background in view, the present research aims to validate the effects of dietary supplementation of customised supplement on feed intake and nutrient metabolism in crossbred calves.

MATERIALS AND METHODS

The experiment was conducted at Animal Nutrition Research Shed, ICAR-Indian Veterinary Research Institute, Izatnagar, during September to October, 2018. Fifteen crossbred calves (Bos taurus x Bos indicus) of about 18 months old with mean body weight (BW) of 166.53±4.93 kg were randomly distributed into 3 groups with 5 calves in each in a completely randomized design. The calves were randomly allocated into three dietary groups as CON (control) and 2 other groups (Treat and SBR). The experimental calves in CON group were fed on cereal straw based diet with concentrate mixture at 20% of DMI as per the farmers’ practices (Ojha et al., 2017), whereas, the calves in Treat (treatment) group were fed according to CON with additional customized supplement at the rate of 0.25% of BW. The calves in SBR (standard basal ration) group were fed standard diet as per Kearl (1982) to meet the nutrients requirement for maintenance and growth. All the calves were dewormed prior to experiment and reared under uniform managemental conditions for a period of 30d. All the calves were housed in well ventilated shed having provision for individual feeding and watering. The chemical composition of feed offered to the experimental calves during the trial period is presented in Table 1.
 

Table 1: Chemical composition of feeds offered (% DM basis).


        
All the calves were individually offered daily a weighed amount of their respective concentrate mixture in the morning at 9.00 AM to meet their nutrient requirements. Wheat straw was provided ad libitum after ensuring complete consumption of the concentrate mixture. About 2.0 kg green maize was also given to all the experimental calves to satisfy the part of their respective nutrient requirements. Wheat straw refusals were weighed daily on the next morning to estimate its consumption per day and was sampled at weekly intervals for subsequent analysis of dry matter (DM) to assess the average DM intake (DMI) during the experimental period. The calves were provided with clean tap water free choice twice daily. The calves were weighed at fortnightly intervals before feeding and watering in order to assess the BW change. To determine the nutrient utilization, balances of nitrogen (N), calcium (Ca) and phosphorus (P), a metabolism trial of eight days that included two days adaptation period and six days collection period was carried out towards the end of feeding trial. During the metabolism trial, the calves were housed in individual metabolism cages made of welded fitted with removable feeders and arrangements for quantitative collection of faeces and urine separately.   
        
Samples of feed offered and refused were collected daily during the metabolism trial. Total daily (24h) faecal and urine outputs were recorded. A sub-sample of the faeces (20%) collected and dried at 100±2°C for 24h in a hot air oven for DM estimation. Pooled samples (6d for each animal) were ground and stored for chemical analysis. For N determination, the faeces samples (2%) were preserved in 25% sulphuric acid to make pooled samples for individual calf. Suitable aliquots of urine (1% v/v) samples, in duplicate, were measured daily into Kjeldahl flasks containing known quantity (40 ml) of laboratory grade sulphuric acid for nitrogen estimation.
        
The data obtained were analyzed using analysis of variance procedures and means were compared using Tukey Test (SPSS Version 20.0). The difference between means was declared significant at P<0.05. Statistical analyses were carried as per the procedures of Snedecor and Cochran (1994).

RESULTS AND DISCUSSION

Chemical composition of feeds
 
The chemical composition (% DM basis) of concentrate mixtures, wheat straw and maize fodder offered to the calves during experimental period is presented in the Table 1. The chemical composition of CON was analogous with the earlier reported values by Ojha et al., (2017). The crude protein content of customized supplement was higher than CON supplement. However, chemical composition of wheat straw and maize fodder was analogous to the values reported by earlier workers (Vaswani et al., 2016; Yengkhom et al., 2018).
 
Intake and digestibility of nutrients
 
The daily intakes of DM and OM (gd-1) were significantly (P<0.01) higher in SBR as compared to Treat and CON groups, while DM and OM intake as % of BW in Treat group has an intermediate position between SBR and CON groups. Intake of concentrate was significantly (P<0.001) higher in SBR followed by Treat and CON, respectively, however, intakes of wheat straw and green maize fodder did not differ significantly (P>0.05) among the treatment groups (Table 2). The results of present study are in accordance with the findings of Zhou et al., (2015), who reported higher intakes of DM and OM in cows fed on high energy diet than on low energy fed diet. Similarly, Hailu et al., (2011) and Tufarelli et al., (2011) also observed higher DM intake in sheep fed higher level of concentrate. Wang et al., (2019) reported that, lambs diet supplemented with 0.5 kg extra concentrate per day had significantly higher DM and OM intake than those fed on control diet. Furthermore, several other reports suggest that, DM intake was significantly increased in buffaloes and sheep fed concentrate containing higher level of CP with additional urea and hypothesized that a proportionate inclusion of NPN compound contributed to improved rumen fermentation and digestibility (McGuire et al., 2013; Sweeny et al., 2014; Kang et al., 2015). The probable explanation for the higher DM intake owing to the fact that, the customized supplement has sufficient fermentable energy, easily degradable N and trace minerals to support and create the conducive environment for the growth of rumen microbes leading to optimized rumen fermentation. A strong positive correlation was observed between dry matter intake (DMI) and microbial growth (Seo et al., 2013; Uddin et al., 2015).  The BW changes (g) and DMI (gd-1, kg) during the experimental trial period was also found to be significantly (P<0.05) higher in SBR and Treat groups as compared to CON (Fig 1).
 

Table 2: Effect of customised supplement on nutrient utilization in calves.


 

Fig 1: Effect of customised supplement on total DMI in calves.


        
The digestibility coefficient of DM, OM, CP, NDF and ADF were significantly (P<0.05) higher in Treat and SBR groups as compared to CON. However, digestibility of EE was found to be significantly (P<0.05) higher in Treat as compared to CON group, whereas, SBR group revealed an intermediate response between CON and Treat groups (Table 2). Similar to our results, Reddy and Reddy (1988) reported that dietary supplementation of energy and protein increased the digestibilities of nutrients in crossbred calves. Similarly, Kang et al., (2015) reported increased digestibility of CP, NDF and ADF in buffaloes fed high protein diet. Khattab et al., (2013) also observed significantly higher digestibility of DM, OM and CP in sheep with increasing dietary urea levels, which could be attributed to the increased growth rate of rumen microorganisms as more available N in form of ammonia from the hydrolysis of urea (Boucher et al., 2007). Furthermore, the dietary protein supplementation increases total tract digestibility in ruminants consuming low-quality forage (Kang et al., 2015). Supplementing the CON diet with synchronous supply of both rapidly fermentable energy and rumen degradable protein through customised supplement had shown a positive associative effect on digestibility of DM by accelerating the growth of rumen microbes (Yulistiani et al., 2015). The increased digestibility of DM, OM, CP, EE, NDF and ADF in the present study may also be attributed to the increased availability of essential nutrients for rumen microbes in Treat and SBR groups that might have fulfilled the specific nutrient requirements for optimizing the rumen microbial ecosystem and overall improved microbial biomass production (Dubey et al., 2011; Wang et al., 2019). The trace minerals are important not only for host but also for microflora prevailing in rumen and influences the nutrient utilization by altering the rumen fermentation as activator of many enzymes like carboxylase, peptidase, dehydrogenase, transferase and arginase (Arelovich et al., 2000; Prasad and Gowda 2005; Mandal et al., 2007).
 
Nitrogen balance
 
Total N intake and retention (gd-1) by calves was significantly (P<0.001) higher in SBR followed by Treat and CON, respectively. The excretion of faeces, urine and total-N (gd-1) was significantly (P<0.001) higher in SBR as compared to Treat and CON groups, however, N-excretion (% intake) was found to be significantly (P<0.01) higher in CON as compared to analogous values between Treat and SBR groups. The N-retention as per cent of intake and absorbed-N (an indication of apparent biological value) was significantly (P<0.001) higher in Treat and SBR groups than CON (Table 3). Our results are in concurrence with the previous reports of McGuire et al., (2013), Kang et al., (2015), who reported that increasing levels of dietary CP in ruminants increased the N intake and N-retention than those fed low dietary CP levels. Islam et al., (2000) and Zhao et al., (2015) also observed that concentrate supplementation was an effective way to improve rumen microbial protein synthesis and shift N excretion from urine to faeces.
 

Table 3: Effect of customised supplement on N balance in calves.


        
It has been well established that the N utilization efficiency can be improved through balanced diet that can synchronously supply adequate fermentable energy and N for maximum microbial growth in the rumen and capture ammonia for protein synthesis (Dijkstra et al., 2011). The higher N-retention as evident in the present study in Treat and SBR groups may be ascribed to the synchronous supply of N and fermentable energy through customised supplement to the rumen for higher microbial protein synthesis and consequently N utilization (Cole and Todd 2008; Dubey et al., 2011).
 
Ca and P balance
 
Intake and retention (gd-1) of Ca and P were significantly (P<0.001) higher in SBR group followed by Treat and CON groups, respectively. The faecal and urinary-Ca excretion as per cent of intake was found to be significantly (P<0.05) higher in CON than SBR, however, Treat group revealed an intermediate response between CON and SBR groups. The faecal-P excretion as per cent of intake was found to be significantly (P<0.05) higher in CON than Treat and SBR groups, however, urinary-P excretion as per cent of intake was comparable (P>0.05) among the groups. The retention of Ca and P (as per cent of absorbed) was significantly (P<0.01) higher in SBR and Treat groups than CON group (Fig 2). Correspondingly, higher Ca and P absorption as evident in our study is in consistency with the report of Yengkhom et al., (2018), who reported significantly higher Ca and P retention in kids supplemented with commercial or customised mineral supplement as compared to non-supplemented control group. Similarly, Gupta (2013) also reported significantly higher Ca absorption in Haryana heifers dietary supplemented with mineral mixture. The significantly higher Ca and P retentions in crossbred calves may be attributed to higher intake and absorption of these minerals through supplementation of minerals through customised supplement in Treat and SBR groups.
 

Fig 2: Effect of customised supplement on Ca and P balance in calves.


 
Nutritive value and plane of nutrition
 
The intake (gkg-1 W0.75) and density (%) of nutrients in terms of DCP and TDN were significantly (P<0.001) higher in SBR group followed by Treat and CON groups (Table 2). Our results are in consistent with the findings of Pandurang (2017), who reported that DCP and TDN intakes were significantly higher in standard control and higher plane of nutrition groups (>10%) than low plane of nutrition fed group (<10%) in calves. Similarly, Pereira et al., (2007) and de Souza Duarte et al., (2011) reported higher TDN intake in crossbred heifers and beef cattle fed high level of concentrate in diet. Ojha et al., (2018) also reported higher DCP and TDN intake in crossbred calves fed standard diet as compared to 15 and 30% restricted diets.
        
The low plane of nutrition of CON (farmers based) diet may be attributed to deficient in readily fermentable energy, degradable protein and essential minerals prerequisite for optimum rumen fermentation. Further, supplementing the CON diet with these limiting nutrients through customized supplement enhanced the DCP and TDN intakes by calves.     

CONCLUSION

On the basis of above results, it can be concluded that supplementation of the customised supplement (@ 0.25% of body weight) to farmers-based diet considerably improved the voluntary feed intake, digestibility of nutrients, N-utilization efficiency and plane of nutrition of crossbred calves.

ACKNOWLEDGEMENT

This study was financially supported by funds provided by the Indian Council of Agriculture Research, New Delhi, India.

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