Comparative studies of reducing level of organic with inorganic trace minerals supplementation on the performance, nutrient digestibility and mineral balance in cross-bred male calves

S Mondal, S K Paul, B Bairagi, M C Pakhira and P Biswas

Department of Animal Nutrition, West Bengal University of Animal and Fishery Sciences,
samik72@rediffmail.com

Abstract

Thirty six crossbred male calves of average 18-20 months old were used to determine the effects of inorganic and organic forms of supplemental copper, zinc, manganese, iron with different dose level on performance, trace mineral concentration in serum, nutrient and mineral utilization. Calves were divided into six groups each having six animals in such a way that mean body weight was similar (P>0.05) among the groups. Each group was assigned to one of the following diets.i) Control (C₀) diet without any trace mineral supplementation. ii) Treatment (T₁) diet with inorganic trace mineral @ NRC (2000). iii) Treatment (T₂) diet with inorganic trace mineral twice the NRC (2000) requirement. iv) Treatment (T_3­­) diet with proteinate trace mineral or Bioplex trace minerals (Alltech Inc. Nicholasville, KY, USA) @ NRC (2000) requirement. v) Treatment (T₄) diet with proteinate trace mineral @ ½ of NRC (2000) requirement. vi) Treatment (T₅) diet with proteinate trace mineral @ 1/4^th of NRC (2000) requirement. Blood samples were collected on days 0, 45 and 90 to determine serum mineral concentration. A metabolism trial of 10 days was conducted during the last two weeks of experiment.

Body weight gain (BWG) and average daily gain (ADG) were found better (P<0.05) in the entire mineral supplemented group compared to C₀ and T₅ after 30 days of supplementation. Mineral supplementation improved (P<0.05) digestibility of different nutrient compared to C₀ and T₅. Mineral intake was found significantly higher (P<0.05) in T₂ followed by T₃ and T₄. Absorption of trace minerals were found significantly (P<0.05)   higher in organic minerals supplemented group (T₃, T₄).Serum mineral concentration of zinc, copper, manganese and iron increased linearly (P<0.05) with the increase of days due to mineral supplementation particularly in organic mineral (T₃ and T₄) supplemented group. So organic mineral supplementation had an important role in growth performance, nutrient utilization, trace mineral balance, serum mineral concentration .Lower dose of organic mineral showed the similar result as inorganic mineral with required amount therefore it reduced excretion as inorganic element and therefore reduced soil toxicity.

Key words: calves, digestibility, mineral, performance

Introduction

Trace mineral deficiencies can occur as a primary deficiency when mineral intake is inadequate or as a secondary deficiency when other factors in the diet interfere with the absorption and metabolism of the concerned trace elements (Olson et al 1999).In order to determine how efficiently an animal utilizes dietary mineral elements, one must know the relative bioavailability of that element from a feed ingredient or complete diet.

Chemical analysis of the diet or an individual feed ingredient does not indicate the biological effectiveness of a nutrient in terms of trace minerals. Bioavailability may be defined as the proportion of an ingested mineral that is absorbed, transported to its site of action and converted to the physiologically active species (O’Dell 1983). Bioavailability of minerals particularly trace elements can be affected by a number of factors including animal species, physiological state, previous nutrition, interaction with other minerals and dietary nutrients, choice of standard source, chemical form and solubility of mineral element, chelators (Ammerman et al 1995).

Studies in different animal have revealed notable differences in the bioavailability of trace mineral from different sources.  Complex trace minerals are said to be more bioavailable than inorganic salts. Studies on the bioavailability of organic and inorganic minerals have reported contrasting results. It was reported that copper proteinate to be more bioavailable than cupric sulphates in studies involving beef cattle (Hemken et al 1993, Ward et al 1993, Wittenberg et al 1990). Kincaid et al (1986) reported that calves fed proteinate form of copper had higher liver and serum level of copper than the calves fed copper sulfate which was suggestive of enhanced bioavailability of copper from the proteinate source. Kropp (1990) found that feeding chelated minerals to 1st calf cows at 30 days before the breeding season caused more cows to exhibit estrus and conceive after 1st service in comparison to inorganic minerals.

Pharmacological responses from feeding high level of trace minerals were observed in feedlot cattle. It was reported  that a 2 years old cow with nutritional stress from calving to breeding may respond to higher levels of trace element than the required amounts (Chirase et al 1991, Nockles et al 1993, Olson et al 1999). So with the knowledge of the bioavailability of trace minerals in feedstuffs and supplemental source is important for economic feed formulation to support optimal animal performance. Under these circumstances the main objective of this study was to investigate the effect of dietary supplementation of organic and inorganic trace minerals at different dose levels on the performance, mineral utilization and nutrient digestibility in cross-bred male calves.

Materials and methods 

Experimental animal and feeding management

Thirty six crossbred male calves of average 18-20 months old were used as experimental animals. Male calves were treated with anthelmentics (Albendazole @10mg/kg body weight) before the start of the study and thereafter at suitable intervals. They were also vaccinated against Haemorrhagic Septicaemia (HS), Black Quarter (BQ), Foot and Mouth Disease (FMD) at the beginning of the experiment so as to keep all the animals in apparently healthy condition and free from any disease. Male calves were individually accustomed with basal diet (both concentrate and paddy straw) according to their body weight to fulfill the dry matter (DM) requirement as per NRC (2000) during 30 days adaptation period. Then the same (along with mineral supplements) was continued for next 90 days of experimental period and 10 days collection period. During the adaptation period all the animals were habituated with the urine collection bags.

Measured amount of concentrate and chopped paddy straw were offered at 8.00 a.m. and 4.00 p.m. and at 9.00 a.m. and 5.00 p.m. daily respectively. Animals had access to ad libitum clean drinking water during the experiment. All the male calves were maintained under uniform managemental conditions with facilities for individual feeding in a concrete trough. After adaptation period (30 days), calves were divided into six groups each having six animals in such a way that mean body weight was similar (P>0.05) among the groups. Each group was fed one of the following diets for a period of 90 days. 1) Control (C₀) diet without any trace mineral supplementation. 2) Treatment (T₁) diet with inorganic trace mineral @ NRC (2000). 3) Treatment (T₂) diets with inorganic trace mineral twice the NRC (2000) requirement. 4) Treatment (T₃) diet with proteinate trace mineral @ NRC (2000) requirement. 5) Treatment (T₄) diet with proteinate trace mineral @ ½ of NRC (2000) requirement. 6) Treatment (T₅) diet with proteinate trace mineral @ 1/4^th of NRC (2000) requirement. NRC (2000) recommendation was followed in formulating the basal diet. Ingredient and chemical composition of basal diet is presented in Table 1.

Trace minerals under study

Only Cu, Fe, Zn and Mn either in organic or inorganic form was taken up for this experiment considering the importance of these traces minerals in livestock productivity and disease resistance.  NRC (2000) recommendation was followed in formulating the ration by supplementation of trace minerals (Cu, Fe, Zn and Mn) at different forms (organic and inorganic) in the diet. Sources and elemental assay of various trace minerals used in this experiment are presented in Table 2.

Record keeping

The body weight of individual male calves was recorded with digital platform balance, standardized with the help of standard weight at the onset of the experiment and thereafter at 15 days interval in the morning before feeding and watering in order to asses the changes in body weight and average daily gain. Body weight gain (BWG) and average daily gain (ADG) were obtained by calculation.

Metabolism trial and sample analysis

A metabolism trial of 10 days duration following 90 days of experimental feeding was conducted to determine the nutrient digestibility, plane of nutrition and mineral balance of the animals. The metabolism trial involved daily recording of feed offered and residue left if any besides total excretion of faeces and urine after allowing for proper acclimatization in metabolic crates. Faeces were collected manually round the clock as quickly as possible in a plastic airtight bucket cum container (capacity of 15 liters) during the collection period and weighed quantitatively. Following thorough and uniform mixing in a plastic trough, representative samples were taken to the laboratory for further processing. Faecal sample was then dried in hot air oven at 100± 5°C for determining the DM content daily. The dried samples of faeces of individual bull calves was subsequently pooled, ground and secured for further analysis. Urine was collected through urine bag and stored in plastic airtight barrel (capacity of 10 liters) kept under the floor of each metabolic crate. The daily urinary output was measured with measuring cylinder. The representative samples were brought to the laboratory in properly marked well-stoppered sample bottles. Suitable aliquots, in duplicate, were measured daily into Kjeldahl flasks containing known quantity of concentrated sulfuric acid for nitrogen estimation. Dried dietary ingredients and faecal samples ground and pass through a 1mmsieve, were analyzed for DM, total ash and organic matter (OM), ether extract (EE) (AOAC, 1995, ID 7.010, 7.016, 7.048). The nitrogen fraction of faeces and urine were estimated in an automatic analyzer (Kjeltech Auto 1013 Analyzer, Foss Tecator, Sweden) and crude protein (CP) was determined by multiplying the N value with 6.25. For analysis of major (Ca, Mg and P) and trace (Cu, Zn, Mn, and Fe) minerals concentration, feed and faecal samples were dried in hot air oven at 105°C for 8 h, ground to pass through 0.5mmsieve and transferred to a glazed ceramic crucible. The samples were ignited at 400 ◦C for 4 h in a muffle furnace. The ash was treated with conc. HNO₃ under mild heat. After complete digestion, the acids were cooled at room temperature and filtered through Whatman grade 1 filter paper (AOAC, 1995, ID 7.073). The crucibles were washed several times with triple distilled water and final volume was made up to 50 ml. Subsequent analysis of major and trace minerals were estimated by flame Atomic Absorption Spectrophotometer (A Analyst 100, Perkin-Elmer Inc., USA) after suitable dilution. Urinary trace minerals were also assayed as per the method of Fernandez and Kahn (1971) with the help of Atomic Absorption Spectrophotometer (Perkin Elmer A Analyst 100).

Collection and processing of blood samples

Pre-supplemental (day 0) and post-supplemental (day 45 and 90) blood samples were collected from the individual male calves in the morning before offering feed. Blood samples were collected aseptically from jugular vein of each male calf using a set of heparinized vacuitainer tube (Becon Dickinson India Pvt. Ltd., New Delhi, India) for mineral estimation. Plasma calcium was estimated with the help of AAS (Perkin Elmer Analyst 100) as per the method adopted by Trudeau and Freier (1967). Plasma sample was diluted to 1:50 with a 0.1% (w/v) lanthanum chloride solution, and the dilution ratio was adjusted to insure that concentrations fall within a suitable absorbance range. The concentration of Ca was expressed as mg/dl.

For determinations of copper, zinc, manganese and iron, plasma samples were diluted to 1:5 with de-ionized water as per method described by Fernandez and Kahn (1971) by using AAS (Perkin Elmer Analyst 100). The concentrations were expressed as ppm (parts per million).

Statistical analysis

Data were analyzed using general linear model of the SPSS (10.0 of 1997) with individual male calves as experimental units. Data obtained during the experimental feeding and collection period were analyzed separately to determine the effects of different form (organic and inorganic) and different dose level of trace minerals. The means were compared using Duncan’s Multiple Range Tests. A probability of P<0.05 was considered to be statistically significant.

Results 

Effect on performance

Growth performance data of experimental male calves of different treatment and control groups during 90 days of feeding trial are presented in Table 3.

No significant (P>0.05) difference could be established between the various treatment groups in respect to body weight gain (BWG) and average daily gain (ADG) in first 30 days of trial but after 30days to throughout the experimental period body weight gain (BWG) and average daily gain (ADG) were significantly improved in all mineral supplemented groups compared to C₀ and T₅. It was also seen that no significant difference was observed in BWG and ADG in inorganic mineral supplemented group and organic mineral supplemented at NRC (2000) required dose and ½ of NRC dose. That means in respect of growth performance organic ½ dose of NRC showed similar performance as inorganic mineral supplemented group.

Effect on nutrient digestibility

Nutrient intake and digestibility of different nutrients in male calves supplemented with different level of inorganic and organic trace minerals have been presented in Table 4.

Intake of different nutrients dry matter(DM), crude protein(CP), crude fibre(CF), ash, Ether Extract(EE), acid insoluble ash(AIA), nitrogen free extract (NFE), organic matter were similar (P>0.05) among different groups but improved (P<0.05)digestibility of DM,CP,CF, ash, EE, AIA, and NFE were observed in all mineral supplemented groups compared to C₀ and T₅ while no significant difference was observed among other mineral supplemented groups. Thus organic mineral in lower amount showed similar result as inorganic in their required dose.

Effect on mineral utilization

Cumulative intake of different trace mineral in 10 days and their absorbability due to supplementation of different inorganic and organic trace mineral are presented in Table 5.

Intake of major mineral were similar (P>0.05) among different groups. Trace minerals intake were significantly higher in group in T₂(inorganic mineral supplemented twice of NRC dose) compared to other followed by other mineral supplemented groups. It was also seen that trace minerals intake were higher in other mineral supplemented groups compared with groups C₀ and T₅, where lower intake was found. In case of absorbability of mineral no significant difference was observed in major mineral absorption among different groups but in trace mineral higher(P<0.05) absorbability percentage was observed mostly in organic mineral supplemented group compared to inorganic mineral. Maximum absorbability (%) was obtained in group T₃ where organic mineral supplement was used per NRC dose. Also it was seen that organic NRC ½ dose (T₄) group showed similar absorbability (%) as inorganic mineral. It was observed that though intake was higher in most mineral supplemented groups except C₀ and T₅, absorption and retention were higher (P<0.05)in organic mineral supplemented groups (T₃ and T₄) and inorganic mineral supplemented group(T₂).So results showed similar absorption and retention for organic (@NRC dose) and inorganic (@twice NRC dose) supplements. Also organic group (@1/2 NRC dose) showed similar results as inorganic group (@ NRC dose).

Effect on serum mineral concentration

Different major and trace mineral concentration in serum of calves of different treatment and control groups are presented in Table 6.

Similar (P>0.05) concentration of Ca and P in serum were found in different groups throughout the experimental period. But in case of trace minerals all the estimated trace minerals increased linearly (P<0.05) due to supplementation of mineral particularly in organic mineral supplemented group(T₃) and inorganic mineral supplemented group(T₂). Highest serum trace mineral concentration was found in group T₃where the group was supplemented with organic mineral @NRC dose. It was also seen that organic mineral supplemented ½ of NRC dose (T₄) group showed similar (P>0.05) serum mineral concentration as inorganic mineral @ NRC dose (T₁). Serum mineral concentration in this mineral supplemented group also increased linearly (P<0.05) with the days due to mineral supplementation and pronounced effect was observed at 90 days of supplementation.

Discussion 

Performance

Trace minerals complexed with organic molecules have been implied to be more bioavailable than inorganic trace minerals (Brown and Zeringue 1994). Researchers (Hemken et al 1993) have indicated that Cu-proteinate may be more available. The physiological advantage afforded by organic Cu compounds may be due to the unique coordination chemistry of element, which permits the formation of highly soluble, chemically stable products that resist interaction with antagonists in the gut (Brown and Zeringue 1994). In this experiment different mineral supplementation improved BWG and ADG of calves. In agreement with the present findings, trace mineral supplementation had improved growth performance in terms of net weight gain and average daily weight gain in cattle (Ward and Spears 1997). In another study, it was reported that organic trace mineral supplementation enhanced reproductive performance and calf average performance like body weight gain compared to inorganic trace mineral supplementation (Stanton et al 2000). Ahola et al (2004) reported that mean body weight and body condition does not differ among different treatment groups of control, inorganic and organic. This is also consistent with the findings of Olson et al (1999) and Muchlenbain et al (2001). Different trace minerals particularly Cu, Mn, Zn function biochemically as a component of several metalloenzymes and as a cofactor for numerous other enzymes (Zapsalis and Beck 1985, Sorensen 1987, Boland 2003). It is possible that different trace minerals enhance growth of calves by stimulating activities of enzymes involved in nutrient utilization.  In the present experiment organic mineral in lower dose was as effective as inorganic mineral with their required dose. This may be possible due to higher bioavailability of organic minerals than inorganic minerals (Du et al 1996, Paik 2001)

Nutrient digestibility

Different trace minerals particularly Cu, Mn, Zn act as a component of several metalloenzymes and as a cofactor for numerous other enzymes. Mn is involved in the activities of several enzyme systems including hydrolases, kinases, decarboxylases, and transferases as well as Fe containing enzymes which require Mn for their activity. It is therefore involved in carbohydrate, lipid, and protein metabolism (Boland 2003). Also Cu is involved in digestion and metabolism of different nutrients through different Cu dependent enzymes (Zapsalis and Beck 1985, Sorensen 1987). In the present investigation trace minerals supplementation in their inorganic and organic form improved digestibility of DM, CP, CF, NFE, OM, and EE. Similar result have been reported in ruminant due to better fermentability and utilization of organic matters mainly soluble carbohydrates at ruminal level when supplemented with minerals(Bhoot et al 1981). It has been reported that supplemental Cu, Mn and Zn facilitate the growth of cellulolytic rumen microbes like Ruminococcus sp. and Fibrobacter sp. which results in better fermentability and utilization of organic matter (Rajora and Pachauri 1998, Budhi and Ternouth 1990, Tiwari et al 2000). In this context, the beneficial effects of trace elements from different sources has been reflected into better body weight gain and performances indicating confirmation of improved bioavailability of various organic nutrients corroborating with the report of Kabaija and Little (1998).Improvement in apparent fat digestibility was observed due to higher activity of lipase and phospholipase A, where Cu is a cofactor of these enzymes (Dove 1995). Due to greater bioavailability of organic mineral, organic mineral in lower dose may be as effective as inorganic mineral with their required dose for improved nutrient utilization.

Mineral utilization

There are many mineral interactions in the feed ration influencing net absorption (Haenlein 2004). Mineral ions compete for anionic ligands to form insoluble precipitates. Mineral ions compete for transport of proteins. So when a trace mineral is ingested its bioavailability is influenced by the specific properties of mineral as it is in the diet. For example, the valence state of mineral and its molecular form (inorganic versus organic) are important. Because of these specific properties the mineral may be inclined to form complexes with other components in the gut which may either hinder or facilitate the mucosal absorption, transport or metabolism of the mineral in the body. That is why certain minerals in the inorganic form will compete with other minerals for the necessary binding and absorption sites in the gut (Miles and Henry 2000).In the present study higher absorbability (%) and retention of trace mineral in calves were found in organic mineral supplemented group and also in inorganic mineral supplemented calves when supplied at twice the requirements. That means organic mineral in lower dose showed similar absorption and retention as inorganic in higher dose. Similar observation was noted by Nockels et al (1993) who reported more apparent absorption in proteinated trace minerals than inorganic salt in case of calves and sheep. In other studies Spears (1996) and Lardy et al (1992) reported chelated form of zinc was retained better (P<0.05) than the inorganic form of zinc.Chelates may utilize peptide or amino acid uptake pathway rather than normal mineral ion uptake pathways in the small intestine. This prevents competition between minerals for the same uptake mechanisms. Not only is bioavailability therefore higher, but these mineral forms are more readily transported and their intestinal absorption is also enhanced (Boland 2003) Inorganic minerals are broken down to varying extent during digestion to free ions and are absorbed. However, they may also complex with other dietary molecules and become difficult to absorb or if completely complexed, totally unavailable to the animal (Boland 2003).

Serum mineral concentration

Present study revealed serum trace mineral concentration of calves increased linearly with the increase of days due to trace mineral supplementation and the effect was more pronounced in group supplemented with organic mineral @NRC dose, Organic mineral @1/2 of NRC dose and inorganic mineral @twice of NRC dose. Similar observation was recorded by Olson et al (1999), who reported that supplementation of trace minerals containing Cu, Mn and Zn in organic and inorganic form raised the serum level of respective minerals compared to the control but within sources only plasma Zn level was found more from organic form than inorganic. In another study Engle et al (2000b) who reported higher (P<0.05) plasma Cu concentration on 84 days due to CuSO₄ and Cu-lysine supplementation. Kegley and Spears (1994) also found enhanced plasma Cu level from both sources of CuSO₄ and Cu-lysine like the present findings. Tambe et al (1998) did not find any improved trace mineral profile on chelated and non-chelated mineral supplementation which was found contrary to the present findings. Higher serum concentration of trace mineral with organic mineral supplementation probably due to higher absorption and retention in tissue level (Boland 2003).

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Received 12 April 2008; Accepted 10 May 2008; Published 3 July 2008

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