Advances in Animal and Veterinary Sciences
Research Article
Effect of Supplementation of Essential Cation, Anion or Combination of Both on the Digestibility of Cation Minerals in Diet of Cows
Kiran Babu S., Bandla Srinivas
Dairy Production, National Dairy Research Institute, Bangalore 560030, India.
Abstract | Study was undertaken to assess the digestibility of essential cation minerals viz., Ca2+, Mg2+, Cu2+, Zn2+, Fe2+ and, Mn2+ when electrovalency of mineral supplement was positive or negative. Lactating Deoni cows were divided into 4 groups of 4 each in completely randomized block design and fed 8 KG fresh para grass, ad lib ragi straw and concentrate supplement without mineral mixture (control) or fortified with essential cation (T1) or anion (T2) minerals or both together (T3). The net electrical charge in the mineral mixtures in T1, T2 and T3 were +0.87, –1.55 and –0.64, respectively. DM (p = 0.96), OM (p = 0.96), CP (p = 0.99), Fe2+ (p = 0.98) and Mn2+ (p = 0.83) intakes were not significantly different between CG and TGs. Net charge in T2 affected CP digestibility adversely (p< 0.05). Ca2+ digestibility was apparently (p = 0.29) higher in T2 and T3. Lack of Phosphorus (P–) source in T1 affected the Ca2+ utilization in comparison to T2 and T3. Mg2+ digestibility was higher (P< 0.05) in T2 and T3 than CG and T1. Cu2+ digestibility was not significantly (p= 0.77) different between groups. Zn2+ (p < 0.01), Fe2+ (p < 0.01) and Mn2+ (p < 0.01) digestibility was significantly different between CG and TGs and appeared that the net electrical charge of mineral mixture influenced the digestibility of opposite ions. Study concluded that cation mineral digestibility was better when net electrical charge of mineral mixture was negative.
Editor | Kuldeep Dhama, Indian Veterinary Research Institute, Uttar Pradesh, India.
Received | August 22, 2014; Revised | September 08, 2014; Accepted | September 09, 2014; Published | September 20, 2014
*Correspondence |Bandla Srinivas, Dairy Production, National Dairy Research Institute, Bangalore 560030, India; Email: [email protected]
Citation | Babu KS, Srinivas B (2014). Effect of supplementation of essential cation, anion or combination of both on the digestibility of cation minerals in diet of cows. Adv. Anim. Vet. Sci. 2 (8): 433-437.
DOI | http://dx.doi.org/10.14737/journal.aavs/2014/2.8.433.437
ISSN (Online) | 2307-8316; ISSN (Print) | 2309-3331
Copyright © 2014 Babu and Srinivas. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
INTRODUCTION
Underwood (1981) suggested 22 essential mineral elements to farm animals based on their concentration in the blood i.e., either >100 or < 100 mg/dl blood plasma and categorised to 7 macro and 15 micro minerals, respectively. Another classification was drawn on the basis of net electrical charge of ions such as cation or anion (Srinivas, 2012), which is relevant in the nutrition of higher forms of animals (Miller, 1981). Delaquis and Block (1995) discussed the dietary anion and cation concept with reference to the systemic acid–base balance of the animal that is basic for all nutrient transportation. Although dietary cation–anion balance (DCAB) is relevant in dairy animals, the concept is restricted to balance between few cations (Na+ and K+) and, few anions (Cl–, S– and P–). This needs to be extended to understand the functional importance of all essential mineral ions supplemented in mineral mixtures (Srinivas, 2012). Present study was conducted with an objective to evaluate the digestibility of essential cation mineral elements when net electrical charge (electrovalency) of mineral ion in the mineral mixtures was positive (cationic) or negative (anionic).
MATERIALS AND METHODS
Animals and Diet
Lactating Deoni cows were randomly distributed into 4 groups of 4 animals each. Cows were fed with 8 KG of fresh para grass (Brachiaria mutica) and ad lib ragi straw (Elusine coracana) at 8 AM and 5 PM, respectively and, supplemented concentrate mixture (consisted of 35 parts of maize, 15 parts of groundnut meal and 50 parts of wheat bran without mineral mixture and common salt) in 2 equal parts twice in a day as per the requirements (ICAR, 1998). Control group (CG) was fed basal diet without additional mineral supplements apart from those naturally present in the diet. Treatment groups (TG) supplemented mineral mixture consisted of only essential cation (T1) or, anion (T2) minerals or, both cation and anion mineral elements together (T3) added to concentrate supplement fed in CG. Composition of mineral mixtures containing cation or, anion mineral compounds is presented in Table 1.
Digestibility Trial
Digestibility trial was conducted after a preliminary period of feeding for 1 month. Trial consisted of 5 d of collection period. Body weight of animals, at zero hour of feeding and watering, recorded for 2 consecutive days before and after the trial. Faecal samples collected during trial period at 8:30 AM and sub-sampled to 1/400 parts. A part of sample was preserved with known quantities of 10 % H2SO4 (V/V) in pre–weighed glass bottles to estimate nitrogen (N). Dried samples of feed offered, left over feed (orts), and faeces were pooled for 5 d for chemical analysis.
Chemical Analysis
Dried samples of feed offered, orts, and faeces analysed for dry matter (DM), organic matter (OM), crude protein (CP) and total ash (AOAC, 2005). Minerals in feed and faecal samples were estimated using inductively coupled plasma (ICP) optical emission spectrometry (Optima 8000, M/s Pelkin elmer, Waltham, U.S.A) after predigesting the samples by modified method of closed system of acid digestion (US–EPA, 2001). The digested samples were cooled and filtered through Whatmann filter paper No1. Repeated washings were given to digestion tube and filter paper using Millipore water and final volume made to 10 ml. Subsequent dilutions were made as for the concentration of the element and estimated important cations viz., calcium (Ca2+), magnesium (Mg2+) copper (Cu2+), zinc (Zn2+), iron (Fe2+) and manganese (Mn2+).
Statistical Analysis
Data were subjected to descriptive statistics and variances between groups mean were compared using CRD based on the following model:
Yij = µ+ Ti + Bj +eij
Where, Yij was any observation for which, µ was population mean, Ti was treatment effect, Bj was block effect, and eij was random error component (Das and Giri, 1991). Pairwise comparison between group means was tested by DMRT and significance was denoted by alpha superscripts with probability (p) ranged from 0.01 to 0.05.
RESULTS AND DISCUSSION
Dicalcium phosphate (Ca2PO4) was used as P– source in the mineral mixtures although it contained cation Ca2+. Similarly, iodide (I–), molybdate (Mo–) and selenite (Se–) sources contained sodium (Na2+) cation. Net electrical charge of the mineral mixtures supplemented in T1, T2 and T3 are presented in Table 2. Total quantity of mineral mixture supplemented in T1, T2 and T3 was 20.18, 18.10 and 31.36 g/d, respectively. Net ion electrical charge of mineral mixtures supplemented in T1, T2 and T3 were +0.87, –1.55 and –0.64, respectively. Chemical composition of the feedstuffs is presented in Table 3. DM (p = 0.96), OM (p = 0.96), CP (p = 0.99), Fe2+ (p = 0.98) and Mn2+ (p = 0.83) intakes were not significantly different between CG and TGs (Table 4). DM intake was numerically higher by 6 % in T2 and T3 where net charge of ions was negative. This is contrary to the observations of Hu et al., (2007). Mg2+ (p < 0.01), Cu2+ (p < 0.01) and Zn2+ (p < 0.05) ions intake were significantly different in CG, T1, T2 and T3.
Table 1: Composition of ion specific mineral supplements.
|
Mineral ion |
Mineral Source |
Mineral supplement of (G/KG DM) |
||
|
Cations |
Anions |
Cations + anions |
||
|
Ca2+ |
Calcium carbonate |
7.58 |
–– |
–– |
|
Mg2+ |
Magnesium carbonate |
1.53 |
–– |
1.53 |
|
Na+ |
Sodium sulphate |
10.28 |
–– |
10.28 |
|
K+ |
Potassium chloride |
1.26 |
–– |
1.26 |
|
Cu2+ |
Cupric carbonate |
0.05 |
–– |
0.05 |
|
Co2+ |
Cobalt carbonate |
0.0005 |
–– |
0.0005 |
|
Zn2+ |
Zinc carbonate |
0.14 |
–– |
0.14 |
|
Ca2+ & P– |
Dicalcium Phosphate |
–– |
18.06 |
18.06 |
|
I– |
Sodium iodide |
–– |
0.003 |
0.003 |
|
Mo– |
Sodium Molybdate |
–– |
0.03 |
0.03 |
|
Se– |
Sodium Selenite |
–– |
0.0025 |
0.0025 |
Table 2: Net charge of the ions in mineral supplements.
|
Mineral ion |
Atomic mass |
Cations |
Anions |
Net charge |
|
CaCO3 |
100.09 |
3.9449 |
3.6351 |
0.3098 |
|
MgCO3 |
84.31 |
0.6590 |
0.8710 |
–0.2120 |
|
Na2SO4 |
142.04 |
5.6483 |
4.6317 |
1.0166 |
|
KCl |
74.55 |
0.6608 |
0.5992 |
0.0616 |
|
CuCO3 |
123.56 |
0.0306 |
0.0194 |
0.0112 |
|
CoCO3 |
118.94 |
0.0003 |
0.0002 |
0.0001 |
|
ZnCO3 |
125.42 |
0.0864 |
0.0536 |
0.0328 |
|
Ca2PO4 |
175.13 |
8.2659 |
9.7941 |
–1.5281 |
|
NaI |
149.89 |
0.0005 |
0.0025 |
–0.0021 |
|
Na2MoO4 |
205.92 |
0.0067 |
0.0233 |
–0.0166 |
|
Na2SeO3 |
188.94 |
0.0007 |
0.0021 |
–0.0014 |
|
Total |
T1 |
10.9687 |
9.2110 |
1.2201 |
|
T2 |
8.2738 |
9.8220 |
–1.5480 |
|
|
T3 |
15.3592 |
15.9968 |
–0.6376 |
Table 3: Chemical composition of diet.
|
Parameter |
Ragi straw |
Green fodder |
Concentrate |
|
DM (g/Kg) |
881 ± 18 |
178 ± 9 |
905 ± 2 |
|
OM (g/Kg) |
896 ± 0.5 |
864 ± 3 |
908 ± 0.4 |
|
CP (g/kg) |
25.60 ± 0.5 |
103.0 ± 0.1 |
20.22 ± 0.2 |
|
Calcium (g/kg) |
10.3 ± 0.25 |
7.13 ± 0.26 |
9.40 ± 0.74 |
|
Magnesium (g/kg) |
10.85 ± 0.24 |
10.15 ± 0.35 |
14.04 ± 1.01 |
|
Copper (mg/kg) |
3.63 ± 0.28 |
55.13 ± 1.92 |
13.10 ± 1.51 |
|
Zinc (mg/kg) |
213.40 ± 19.27 |
226.35 ± 5.07 |
470.40 ± 33.34 |
|
Iron (mg/kg) |
95.88 ± 3.63 |
1341.00 ± 77.94 |
477.60 ± 22.60 |
|
Manganese (mg/kg) |
384.90 ± 6.25 |
80.17 ± 5.05 |
126.30 ± 12.60 |
CP digestibility was significantly reduced (p < 0.05) in T2 which could be probably because of more net negative charge of ions in the mineral mixture. Hu et al., (2007) reported adverse impact of net negative charge on CP digestibility in dairy cows. Although net electrical charge in T3 was negative, CP digestibility was not reduced. Considering the result of Hu et al., (2007) as well as CP digestibility observed in this study, we presume that CP digestibility might be affected only beyond a threshold level of net negative electrical charge probably less than –1. Contrary to the observation of Popplewell et al., (1993) on cation and anion balance in the diet of dairy cows, no significant impact of net charge of mineral supplements on DM and OM digestibility were observed between CG and TGs. Ca2+ digestibility was negative in few replicates and indicated individual cow variation. Ca2+ digestibility was apparently (p = 0.29) higher in T2 and T3. Probably lack of P– source in the cationic mineral mixture affected the Ca2+ utilization in T1. In general, the ideal ratio of Ca2+ and P– intake is 1:2 to 2:1 (Horst et al., 1994). Ca2+ to P– ratio in Ca2PO4 is about 2:1. Mg2+ intake (p < 0.01), and digestibility (p < 0.05) were significantly different in CG and TGs. Mg2+ digestibility was higher in T2 or T3 than CG and T1. Mg2+ digestibility improved in T2 where mineral mixture consisted of anion mineral elements i.e., net electrical charge was negative. Weiss (2004) reported that mean apparent digestibility of Mg2+ was ranging from –0.04 to 0.33. According to NRC (2001), optimum Mg2+ digestibility is 43 %. Mg2+ digestibility in diet can be affected by increased K+ intake above the stipulated requirement in the diet (Weiss, 2004).
Intake of Cu2+ was significantly (p < 0.01) different between CG and TGs but, digestibility was not significantly (p = 0.77) affected Cu2+ in CG utilized more efficiently because it was in lower concentration than in TGs. According to Ivan and Grieve (1975) Cu2+ concentration in liver was inversely proportional to the dietary Zn2+ and, directly proportional to dietary Mn2+ supplementation. Mn2+ was not added in the cation mineral mixture but, Zn2+ was included. Zn2+ intake in CG or TGs was 15 folds higher than Cu2+. According to Weiss (2004), Zn2+ intake should not exceed the dietary Cu2+ intake by more than 5 folds. Probably, higher ratio of Zn2+ in the mineral mixture decreased the Cu2+ utilization even though both the elements incorporated as per the requirements (NRC, 2001). Zn2+ intake (p < 0.05) and digestibility (p < 0.01) were significantly different in CG and TGs. Significantly higher digestibility in T3 (59 %) than T1 (39 %) indicated that Zn2+ digestion improved in the presence of anion minerals such as P–, I–, Mo– and Se–. Fe2+ intake was not significantly (p = 0.98) different between CG and TGs because, it was not fortified in the cation or cation + anion mineral mixture since Fe2+ availability from the diet was sufficient to meet the requirements. Fe2+ digestibility was negative in CG (–4 %) and significantly lesser than TGs (p < 0.01). Fe2+ digestibility was comparable between T2 (23 %) and T3 (36 %) but not with T1 (2 %). Fe2+ utilization also improved in the presence of anions; P–, I–, Mo– and Se–, present in T2 and T3. Mn2+ intake was not significantly (p= 0.83) different as its availability in the basal diet was sufficient to substantiate requirement.
Table 4: Feed and mineral intake and digestibility in different groups
|
Parameter |
Control |
Mineral supplement (g/Kg DM) |
SEM |
||
|
Cations |
Anions |
Combined |
|||
|
Nutrient intake |
|||||
|
DM intake (kG/d) |
6.46 |
6.40 |
6.60 |
6.61 |
0.35 |
|
OM intake (kG/d) |
5.76 |
5.71 |
5.89 |
5.89 |
0.31 |
|
CP intake (g/d) |
648.75 |
638.90 |
645.4 |
653.13 |
36.52 |
|
Calcium (g/d) |
57.83a |
71.65bc |
65.42ab |
76.65c |
2.51* |
|
Magnesium (g/d) |
67.29a |
76.28b |
65.41a |
77.59b |
2.04** |
|
Copper (g/d) |
0.12a |
0.17b |
0.12a |
0.18b |
0.01** |
|
Zinc (g/d) |
1.78ab |
1.94b |
1.78a |
1.99b |
0.07* |
|
Iron (g/d) |
3.05 |
3.03 |
3.00 |
3.09 |
0.13 |
|
Manganese (g/d) |
1.45 |
1.48 |
1.55 |
1.52 |
0.08 |
|
Digestibility coefficient |
|||||
|
DM |
56.68 |
56.16 |
57.09 |
55.97 |
1.44 |
|
OM |
58.96 |
58.65 |
59.69 |
58.68 |
1.42 |
|
CP |
54.45b |
54.56 b |
48.49a |
56.10 b |
1.65* |
|
Calcium |
4.87 |
14.46 |
23.56 |
31.23 |
9.40 |
|
Magnesium |
33.26a |
31.95a |
45.15b |
47.96b |
4.06* |
|
Copper |
62.59 |
58.11 |
55.53 |
58.54 |
4.74 |
|
Zinc |
27.43a |
39.16b |
36.17ab |
58.56c |
3.14** |
|
Iron |
–4.96a |
2.40ab |
23.43bc |
35.78c |
7.05** |
|
Manganese |
41.46a |
44.54ab |
55.12bc |
64.15c |
3.50** |
Mean values in a row with different superscripts a, b, c vary significantly; *P < 0.05, **P < 0.01
Digestibility of Mn2+ was significantly (p < 0.01) different between CG and TGs. Mn2+ utilization also improved when net ion charge was negative. Cations homeostasis is partially dependent on endogenous faecal excretion controlled by the intestinal tract, liver and pancreas while, anions homeostasis is partially dependent on renal excretion (Buckley, 2000) thus, enumerating both the ions are mutually exclusive but collectively exhaustive. According to Block (2011), subjects such as ratios of Ca2+ to P and N to sulphur, interactions between Mg2+ and K+, Mn2+ and Cu2+, and vitamin E and Se have been investigated and addressed however, no unifying concepts on mineral balances have been proposed yet. Our result indicated that utilization of some of the cation mineral elements e.g., Ca2+, Mg2+, Zn2+, Fe2+ and Mn2+ were improved in the presence of anion mineral elements P–, I–, Mo– and Se–.
CONCLUSIONS
Study revealed that interaction between electrical charge carried by the cation and anion group of minerals in the mineral mixtures and their net electrovalency influenced the digestibility. Digestibility of cation mineral elements improved when net ion charge was negative.
REFERENCES
