ROLE OF CHELATED MINERAL TO IMPROVE THE PRODUCTIVITY OF LIVESTOCK AND POULTRY
Suresh.C1* and Sujatha.V2
- Corresponding author & Assistant Professor and Head, Veterinary University Training & Research Centre, Nagapattinam-611 001
- Assistant Professor, Farmers Training Centre, Tiruvarur – 610 004.
TANUVAS – Tamil Nadu Veterinary and Animal Sciences University, Chennai, Tamil Nadu, India-600 051
*-Corresponding Author Email I.D:drsureshthambi@gmail.com
Minerals are included in the livestock ration at very small amount in the form of premix of inorganic salts such as sulphates, chlorides, carbonates and oxides. In general, feed manufacturers use much higher concentrations of minerals than the safety levels in livestock and poultry feed to achieve optimum performance. Because of wide safety margins in supplementation level, the majority of inorganic trace minerals are excreted as waste, with very low body retention. High inorganic mineral supplementation is not only wasteful, but perhaps also harmful to the environment. Dozier et al. (2002) reported that poultry manure, as applied on nitrogen basis, contained 660% zinc and 560% copper in excess of crop requirement. The possible reasons of low body retention of trace minerals could be ascribed to their tendency to dissociate in the low pH environment of upper gastrointestinal tract, leaving the minerals susceptible to various nutrients and ingredient antagonisms that impair absorption (Underwood and Shuttle, 1999). Patton (1990) stated that the absorption of each mineral could be affected directly by the nutritional body balance of that specific mineral. In addition, phytic acid form complexes with trace minerals those are very stable and highly insoluble, rendering the minerals unavailable for absorption (Leeson and Summers, 2001). Enhanced bioavailability of mineral source (more specifically organic minerals or chelated minerals) can potentially reduce the amount of a mineral that is added to a diet to meet nutritional requirement, leading to reduced amount of mineral excretion.
The term “organic mineral” refers to a variety of compounds including metal-amino acid complexes, metal amino chelates, metal proteinates, metal-polysaccharide complexes, metal-yeast complexes and metal-organic acid complexes (Patton, 1990). Ashmead et al. (1993) reported about the chemical inertness of the metal amino acid chelates because of the covalent and ionic bonds between the minerals and the ligand, and opined that these minerals remained unaffected by the factors those lead to precipitation, unlike the minerals ionized after salt solubilisation in case of inorganic minerals. Enhancing trace mineral bioavailability is the main aim of using organic sources of minerals. The principle is to bind minerals to organic molecules (ligands), allowing the formation of structures with unique characteristics and high bioavailability. Variability in availability of organic minerals was reported by many authors, which might be related to their ability to remained chelation during solubilisation (Guo et al., 2001).
Bioavailability
Measuring the deposition or storage of minerals in selected tissue (tibia or plasma zinc, liver copper and tibia manganese) is most common output in trace mineral relative bioavailability experiments (Underwood and Shuttle, 1999). Bioavailability can be affected by a number of factors including animal species, physiological state, previous nutrition, interactions with dietary nutrients and ingredients, choice of response criteria, choice of standard source, chemical form and solubility of the mineral element (Ledoux and Shannon, 2005). Organic mineral sources like amino acid complexes or proteinates have higher bioavailability in comparison to inorganic minerals that are traditionally used in livestock and poultry ration (Yan and Waldroup, 2006). The gel filtration chromatography studies of Guo et al. (2001) and Cao et al. (2000) indicated that very little of the copper and zinc remained in the chelated form at pH 2. Considering this finding, question pertaining to the absorption of organic minerals as such in the intestine appeared to be questionable. However, some studies revealed low minerals interaction on use of organic minerals. Excess of molybdenum and sulphur in the diet reduces copper absorption. Some studies revealed the influence on the availability of copper on using organic copper sources. Higher bioavailability of copper from copper proteinate compared with copper sulfate in calves fed diets containing molybdenum was reported by Kincaid et al. (1986) while Ward et al. (1993) found no difference in copper bioavailability between copper sulfate and copper lysine regardless of dietary Mo and sulfur levels. Qin et al.(2007) observed higher total Se concentration in kidney, liver and muscle of lambs supplied with 0.1 ppm of selenium as selenium yeast for 8wk as compared to sodium selenite supplemented group. Zhan et al. (2007) observed increased Se content in blood serum, muscle, liver and kidney of pigs supplemented with 0.3ppm organic selenium for 40 days. The differences in level of bioavailability associated with organic sources might be due to variable concentrations of minerals and organic ligands (Ledoux and Shannon, 2005).
Organic trace minerals have been shown to affect meat quality through reduced cooking loss (Saenmahayak et al., 2007). In addition, fillet color measurements indicated that broilers fed organic trace minerals showed darker fillets, which may be correlated with a lower incidence of pale, soft and exudative meat. Zhan et al. (2007) observed that 0.3 ppm dietary organic selenium to finishing pigs for 40 days had no effect on pH, myoglobin content of muscle. Svedaite et al. (2009) observed that feeding a diet containing 0.1 ppm Se and 20 IU of vitamin-E to pigs for 4 months had no effect on meat pH and color intensity.
Chelated Mineral in Dairy cows
Marginal mineral deficiencies, under low levels of production, become more severe with increased levels of production, and previously unsuspected nutritional deficiency signs usually occur as production levels increase (McDowell, 2002). To meet the higher need of minerals for supporting the increased milk production, organic minerals were supplemented in the lactating dairy animal rations and some of the experimental findings are elucidated for a comparative study. The experimental findings of many researchers revealed that supplementing organic minerals tended to increase both total milk production and production of milk components in the first calf heifers more than was possible with inorganic mineral supplementation (Ashmead and Samford, 2004). Positive effect on milk yield by supplementing cows with organic trace minerals were also reported by Ballantine et al. (2002), Nocek et al. (2006) and Griffiths et al. (2007). Ballantine et al. (2002) and Griffiths et al. (2007) reported higher protein level in the milk on supplementation of organic trace minerals to the dairy animals. As regard to fat level in the milk, higher fat levels were reported by Ballantine et al. (2002), Nocek et al. (2006) and Griffiths et al. (2007). The exact metabolic pathway(s) of organic minerals in increasing milk production or milk components need to be elucidated. Determining whether the observed improvements are a direct result of the enhanced uptake of minerals from the organic minerals source or a consequence of increased amounts of minerals interacting with other nutrients essential for milk and milk component production requires further study (Ashmead et al., 2004). In contrast, Ramos et al. (2012) reported that organic trace mineral supplementation did not affect the overall milk production, milk fat, milk protein content and sometic cell count in the milk. Similarly, no significant effect on milk yield by supplementing cows with organic trace minerals were reported by Uchida et al. (2001). No difference in milk fat yield (Uchida et al., 2001) and milk protein percentage during the first or second lactation (Nocek et al., 2006) were also reported while comparing inorganic versus organic mineral supplementation to lactating cows.
Positive effects of organic minerals supplementation on reproductive indices in dairy animals were reported by many authors. In heifers, the study on organic minerals supplementation as reported by Ashmead et al. (2004) revealed that the organic mineral supplemented heifers displayed estrus by 113 days while in the inorganic mineral group, estrus occurred in some animals as late as 206 days post-calving. As regard to first service conception rates, Ballantine et al. (2002) reported increased first service conception rates while Griffiths et al. (2007) reported no difference on organic minerals supplementation to dairy cows. Several studies have also reported improvements in reproductive performance, immune response and hoof health in ruminants supplemented with these minerals (Nocek et al., 2000). The better reproductive performances as reported by many authors in dairy animals on organic mineral supplementation might be due to increased concentration of minerals in their uterine tissue. Manspeaker et al. (1987) demonstrated that supplemental metal amino acid chelates were more bioavailable than inorganic metal salts and resulted in improved reproductive `performance. Many authors reported no difference between the organic and inorganic minerals supplementation on the reproductive indices of dairy animals. Lamb et al. (2008) also reported no differences in follicular growth, as measured by follicle number, follicle size and number of follicles that ovulated, in superovulated Angus heifers whether they received inorganic, or organic trace mineral supplementation for 23 d before embryo collection.
Chelated Mineral in Poultry
Abdallah et al. (2009) reported that the body of weight birds at 35th day fed with 100% organic zinc were significantly higher than the group fed with 50% organic and 50% inorganic zinc and group fed with 100% inorganic zinc. But Zhao et al. (2010) reported no significant difference with respect to body weight in poultry by replacing inorganic copper at 50% and 100% level with organic. Mishra et al. (2013) reported that supplementation with zinc-methionine resulted in better body weight of broilers than that of organic copper, organic manganese and from their respective inorganic mineral supplemented broilers. Paulicks and Kirchgessner (1994) found a positive effect of zinc supplementation on egg production of laying hens while Soni et al. (2014) reported that the overall hen day egg production and feed conversion ratio of the broiler breeders from 32 to 48 weeks did not differ significantly in both organic and inorganic zinc fed groups. Various workers also had reported no significant effect of zinc supplementation on body weight of broilers either in inorganic form or supplementation with organic zinc (Rossi et al., 2007; Zhao et al., 2010). But Idowu et al. (2011) reported that the mean body weight of layers in control and ZnCl2 groups were significantly lower than that of zinc-proteanate group. Considering the essential role of zinc in egg production, various authors reported on supplementation of organic zinc on the egg quality traits of layers and breeders. Idowu et al. (2011) reported that egg quality parameters viz. egg weight, egg length, egg breadth, albumen weight, albumen height, yolk weight, dry shell thickness, dry shell weight and shell index of control group did not differed significantly with that of zinc-proteanate fed group. Kidd et al. (1992) reported that on feeding of zinc both from inorganic and organic sources did not have any significant effect on egg weight and chick weight. Similar findings were also reported by Tabatabaie et al. (2007). But, Hudson et al. (2004) reported better egg quality parameters in organic zinc fed groups than inorganic zinc fed group. Kidd et al. (1992) reported that on feeding of zinc both from inorganic and organic sources did not have any significant effect on the hatchability. Soni et al. (2014) reported that the fertility percent, hatchability percent (on total egg set basis/on fertile egg set basis) of the broiler breeders from 32 to 48 weeks did not differ significantly in both organic and inorganic zinc fed groups.
Role of Chelated minerals in Immunity
As regard to effect on immunity and antioxidant status Fekete and Kellems (2007) found that deficiency of copper, iron, zinc and selenium in animal is associated with signs of immunodeficiency. In addition, the trace elements (Cu, Zn. Fe, Mn and Se) are involved in the metabolic activities via metalloenzymes, which are essential for the antioxidant protection of the cells (Ozturk-Urek et al. 2001). Role of organic minerals in improvement of immunity was reported by many researchers. Soni et al. (2013) reported that the influence on primary antibody titre to SRBC was significantly lower in inorganic zinc group than that of organic zinc fed broiler breeder groups. Hudson et al. (2004) reported that immune response to PHA-P injection was enhanced when dietary zinc supplementation was solely from zinc- aminoacid (ZnAA). Stahl et al. (1989) reported that zinc as zinc- methionine supplementation (100 mg/kg zinc to a basal diet containing 36.8 mg/kg zinc) had better effect on primary immune response to SRBC relative to control. Researcher has demonstrated that supplementing broiler breeder hen diets with zinc-methionine rather than inorganic zinc sources increased cellular immune response of progeny to PHA (Virden et al., 2004). Shinde et al. (2006) concluded that supplementation of 20 ppm zinc significantly improved immune response and impact was more prominent with ZnAA compared to zinc sulphate. Kidd et al. (1992) reported no significant difference in immunity of birds on supplementation of organic zinc while comparing with inorganic zinc supplementation. Moghaddam and Jahanian (2009) reported that supplementation of zinc methionine partially or completely in place of inorganic sources in the ration of poultry birds had not much influence on primary antibody titre to SRBC. Pimentel et al. (1991) reported that zinc supplementation (80 mg/kg zinc from ZnSO4) had lower effect on primary immune response to SRBC relative to control.
Most of the reports on organic Se supplementation in the diet of different species of animals have shown an enhancing effect on blood glutathione peroxidase (GSH-Px) activity. Kaur et al. (2003) observed higher activity of antioxidant enzymes (lipid peroxidase (LPO), catalase and glutathione peroxidase) by supplementation of 0.25 mg sodium selenite/ kg body weight daily for 6 weeks. Cerri et al. (2009) observed that supplementation of 0.3 ppm organic and inorganic Se in dairy cows from 25 days before calving to 70 days of lactation had no effect on serum glutathione peroxidase activity. Kumar et al. (2009) observed increased glutathione peroxidase activity in lambs given 0.15 ppm of organic Se for 90 days than inorganic Se supplemented animals.
Cortinhas et al. (2012) reported that feeding organic sources of Zn, Cu and Se to cows reduced the number of subclinical mastitis cases, without any alternation in the concentration of serum superoxide dismutase, glutathione peroxidase or ceruloplasmin. Kumar et al. (2009) observed increased humoral immunity in lambs given 0.15 ppm of organic Se (Jevsel-101) for 90 days than inorganic Se supplemented groups.
Conclusion
Bioavailability of chelated minerals was higher than the inorganic salts. Chelated minerals supplementation ensures the lesser excretion of excess minerals. Precise mineral nutrition to livestock and poultry can be achieved by supplementation of chelated minerals to different classes of livestock and poultry.
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