**9. Impact of nanominerals on layers**

Eggs and meat are the primary products of poultry industry which are widely accepted, consumed and provides the quality nutritional security to the human race. The huge demand of poultry products intensifies the production system and improving the productivity becomes the major focus of research. The composition and nutrient density of poultry diets affect composition and nutritional quality of eggs and their products [82]. Considering the layer birds, precise mineral nutrition is very important to maintain the egg production and egg production is very susceptible to minute deficiency of many minerals. Several studies have been conducted to validate the effects of nanominerals in layers and their effects on egg productions are documented.

**69**

*Essential Nanominerals and Other Nanomaterials in Poultry Nutrition and Production*

Calcium is required for egg shell formation; hence its requirement in layer diets is very high to sustain egg production. On adding 1 g/L of Ca carbonate NP in water, Wang et al. [83] could find stronger eggshell strength and better freshness indexed eggs as compared to the control. However, Ganjigohari et al. [84] reported a drop in egg production percentage, egg mass and low blood Ca level by reducing 4.03% of Ca carbonate by 0.126% Ca carbonate NP in laying hens as compared to birds supplemented with 4.03% of Ca carbonate replaced by 2.02%, 1.01%, 0.25% Ca carbonate NP, which would be due to too much reduction in the Ca level in the bird's diet. Similarly, Zn supplementation is obligatory to improve egg production and quality [1]. Being a part of enzyme carbonic anhydrase, Zn is required during egg shell formation and thus deficiency of Zn results in poor eggshell quality. Zn also interrelate Ca crystals during eggshell synthesis [85] which indirectly affects formation of shell membrane and eggshell. Abedini et al. [85] reported an improvement in feed intake, egg mass, egg Haugh unit, eggshell thickness and strength, and tibia ash content and strength at 40 and 80 mg Zn/kg diet as ZnO NP in the laying hens. Tsai et al. [86] observed a hike in Zn retention, thickness of the eggshell, concentration of growth hormone in the blood serum and carbonic anhydrase in nano-Zn supplemented groups as compared to control, without affecting the immunity and other nutrient retention in birds. However, no effect of different dietary Zn sources such as inorganic, organic or nano-Zn on egg quality parameters namely, egg mass, eggshell weight, and eggshell breaking strength [87, 88]. An increase in Zn content in egg yolk due to supplementation of nano-Zn may be proved advantageous to produce designer egg and aid in better keeping quality [82]. Olgun and Yildiz [89] observed highest egg weight and the lowest eggshell thickness by supplementation of nano Zn at 50, 75 and 100 mg per kg diet as compared to Zn-sulphate and Zn-oxide and Zn-glycine supplemented birds and thus, suggested nano-Zn supplementation negatively affects the eggshell thickness and bone mechanical properties. However other studies reported positive responses by supplementation on nano-Zn [82, 85]. The malondialdehyde content in egg was reduced in the groups supplemented with Zn-oxide NP at 80 mg Zn/kg diet [87] and 40 mg/kg of Zn-oxide NP [66], respectively. Dietary Se has a significant role in egg production and immunity in poultry and reports suggests better responses of nano-Se as compared to its conventional counterparts. Radwan et al. [56] reported that use of nano-Se improved Se content in eggs, egg production and feed conversion ratio without affecting egg weight, feed intake in birds. Qu et al. [90] supplemented Se-NP at 0.5 mg/kg diet in laying hens and reported improved rate of egg production, glutathione peroxidase (GPx) activity, total antioxidant status, along with decreased soft-shelled or cracked egg rate. Meng et al. [53] observed an increase in egg Se concentration by supplementation of Nano-Se at 0.3 mg/kg as compared to sodium selenite, Se-yeast. However, they observed that Se-yeast and nano-Se were better retained in the body than sodium selenite. It is observed that injection of nano-Se and nano-ZnO lessened the negative effects of heat stress by increasing antioxidant activity and reducing oxidative stress [91]. Shokraneh et al. [91] observed increased activity of GPx and superoxide dismutase (SOD) and total protein and decreased the levels of corticosterone, cortisol, T4 and T3 in the eggs being injected with NaCl solution containing 40 μg nano-Se at high eggshell temperature. In ovo injection of Cu-NP on 1st and 10th day of incubation showed decreased oxygen consumption, lower heat production, higher residual yolk sac weight compared with the control group, signifying reduced lipid oxidation in Cu-NP injected group [92]. Supplementation of nano-Cu in poultry has shown varied effects depending on dose administered. For an instance, in ovo supplementation of nano-Cu and Cu-sulphate NP at 50 mg hiked the red blood cells and white blood cells in poultry [93], while at a dose of 0.3 mL containing 50 mg/L nano-Cu improved the expression of pro-angiogenic

*DOI: http://dx.doi.org/10.5772/intechopen.96013*

#### *Essential Nanominerals and Other Nanomaterials in Poultry Nutrition and Production DOI: http://dx.doi.org/10.5772/intechopen.96013*

Calcium is required for egg shell formation; hence its requirement in layer diets is very high to sustain egg production. On adding 1 g/L of Ca carbonate NP in water, Wang et al. [83] could find stronger eggshell strength and better freshness indexed eggs as compared to the control. However, Ganjigohari et al. [84] reported a drop in egg production percentage, egg mass and low blood Ca level by reducing 4.03% of Ca carbonate by 0.126% Ca carbonate NP in laying hens as compared to birds supplemented with 4.03% of Ca carbonate replaced by 2.02%, 1.01%, 0.25% Ca carbonate NP, which would be due to too much reduction in the Ca level in the bird's diet. Similarly, Zn supplementation is obligatory to improve egg production and quality [1]. Being a part of enzyme carbonic anhydrase, Zn is required during egg shell formation and thus deficiency of Zn results in poor eggshell quality. Zn also interrelate Ca crystals during eggshell synthesis [85] which indirectly affects formation of shell membrane and eggshell. Abedini et al. [85] reported an improvement in feed intake, egg mass, egg Haugh unit, eggshell thickness and strength, and tibia ash content and strength at 40 and 80 mg Zn/kg diet as ZnO NP in the laying hens. Tsai et al. [86] observed a hike in Zn retention, thickness of the eggshell, concentration of growth hormone in the blood serum and carbonic anhydrase in nano-Zn supplemented groups as compared to control, without affecting the immunity and other nutrient retention in birds. However, no effect of different dietary Zn sources such as inorganic, organic or nano-Zn on egg quality parameters namely, egg mass, eggshell weight, and eggshell breaking strength [87, 88]. An increase in Zn content in egg yolk due to supplementation of nano-Zn may be proved advantageous to produce designer egg and aid in better keeping quality [82]. Olgun and Yildiz [89] observed highest egg weight and the lowest eggshell thickness by supplementation of nano Zn at 50, 75 and 100 mg per kg diet as compared to Zn-sulphate and Zn-oxide and Zn-glycine supplemented birds and thus, suggested nano-Zn supplementation negatively affects the eggshell thickness and bone mechanical properties. However other studies reported positive responses by supplementation on nano-Zn [82, 85]. The malondialdehyde content in egg was reduced in the groups supplemented with Zn-oxide NP at 80 mg Zn/kg diet [87] and 40 mg/kg of Zn-oxide NP [66], respectively. Dietary Se has a significant role in egg production and immunity in poultry and reports suggests better responses of nano-Se as compared to its conventional counterparts. Radwan et al. [56] reported that use of nano-Se improved Se content in eggs, egg production and feed conversion ratio without affecting egg weight, feed intake in birds. Qu et al. [90] supplemented Se-NP at 0.5 mg/kg diet in laying hens and reported improved rate of egg production, glutathione peroxidase (GPx) activity, total antioxidant status, along with decreased soft-shelled or cracked egg rate. Meng et al. [53] observed an increase in egg Se concentration by supplementation of Nano-Se at 0.3 mg/kg as compared to sodium selenite, Se-yeast. However, they observed that Se-yeast and nano-Se were better retained in the body than sodium selenite. It is observed that injection of nano-Se and nano-ZnO lessened the negative effects of heat stress by increasing antioxidant activity and reducing oxidative stress [91]. Shokraneh et al. [91] observed increased activity of GPx and superoxide dismutase (SOD) and total protein and decreased the levels of corticosterone, cortisol, T4 and T3 in the eggs being injected with NaCl solution containing 40 μg nano-Se at high eggshell temperature. In ovo injection of Cu-NP on 1st and 10th day of incubation showed decreased oxygen consumption, lower heat production, higher residual yolk sac weight compared with the control group, signifying reduced lipid oxidation in Cu-NP injected group [92]. Supplementation of nano-Cu in poultry has shown varied effects depending on dose administered. For an instance, in ovo supplementation of nano-Cu and Cu-sulphate NP at 50 mg hiked the red blood cells and white blood cells in poultry [93], while at a dose of 0.3 mL containing 50 mg/L nano-Cu improved the expression of pro-angiogenic

*Advances in Poultry Nutrition Research*

in broiler chickens. Mishra et al. [48] fed layer birds with extremely low levels of nano-Zn (1/500th of basal dose) and obtained similar growth promoting effect. Likewise, Ahmadi et al. [65] observed increased body weight gain, feed intake, and feed efficiency at 60 and 90 mg/kg diet of ZnO NP, but exhibited a lower performance in chickens at a dose of 120 mg/kg diet, whereas Fathi [66] reported lower feed efficiency in birds by supplementing nano-ZnO at 40 mg/kg. In contrast, feed intake, body weight gain, feed efficiency and, carcass traits were not affected due to supplementation of nano-ZnO at 25 and 50 mg/kg as well as ZnO at 100 mg/kg [50]. Nano-Zn at 80 mg/kg increased Zn, Ca and P levels, bone dimensions, weight, total ash along with higher liver and muscle Zn concentration [74]. Significantly lower fat and cholesterol content and better antioxidant status was obtained by supplementation of nano-Zn than inorganic Zn at 80 mg/kg [74]. Nano-ZnO increased mRNA expressions of insulin like growth factor-1 and growth hormone

genes in broiler chickens compared to the inorganic or organic Zn [75].

Nano-Cr increased protein contents in thigh and breast muscles and lowered fat and cholesterol concentrations in thigh muscles. Chromium NP at 0.5 mg/kg diet improved breast and thigh muscle protein content, average daily gain and feed efficiency and lowered cholesterol and fat in thigh muscles of the broilers [76]. However, supplemental nano-Cr picolinate at 0.5 and 3 mg/kg [58] or 0.4 mg/kg [59] of Cr did not affect body weight, feed intake, feed efficiency, and egg production of layer birds. Supplementation of nano-Cr at 0.8 mg/kg diet was effective in reducing the negative effects of induced stress on meat quality of quail broilers, as evident from reduced malondialdehyde concentration in the thigh muscle and unaltered hematological parameters [77]. CuO NP was more efficient in increasing growth performance and immunity compared with the conventional sources of Cu [78]. As compared to the inorganic salts, supplementation of nano-Se improved the body weight gain and lowered the feed to gain ratio at doses up to 0.30 mg/kg diet, beyond which no beneficial effect was recorded [52, 54]. Se-yeast and nano-Se resulted in better growth performance than sodium selenite at 0.2 mg/kg Se [79]. Nano-Se supplementation reduced drip loss percentage without altering weight gain, feed intake, and feed conversion, meat color or immune organ index (thymus, bursa, and spleen) in broilers [57]. However, Se supplementation irrespective of its source (sodium selenite or nano-Se) increased daily weight gain and feed efficiency [67], though nano-Se proved to be more efficient. Improved weight gain and feed conversion due to supplementation of Fe NP (7 mg/kg) was possibly due to increased arginine in liver [80]. Dietary Fe sulfate NP resulted in highest jejunal villi width and surface area in broiler chickens at 21 and 42 days of age [81]. Overall, above studies that nano-minerals at reduced dose rates have potential to improve growth performance and the quality of meat compared with the conventional mineral sources.

Eggs and meat are the primary products of poultry industry which are widely accepted, consumed and provides the quality nutritional security to the human race. The huge demand of poultry products intensifies the production system and improving the productivity becomes the major focus of research. The composition and nutrient density of poultry diets affect composition and nutritional quality of eggs and their products [82]. Considering the layer birds, precise mineral nutrition is very important to maintain the egg production and egg production is very susceptible to minute deficiency of many minerals. Several studies have been conducted to validate the effects of nanominerals in layers and their effects on egg productions

**68**

are documented.

**9. Impact of nanominerals on layers**

and pro-proliferative genes [94], and also improved the bone characteristics at 42 days birds which signified the possible effect of nano-Cu in bone development and maintenance [95]. The better performances in poultry by in ovo injection of nano-Cu was attributed to improved metabolic rate during embryogenesis resulting in amplified performance of broiler chickens after hatching [96]. Supplemental nano-Cr-picolinate at 0.5 and 3 mg/kg of Cr improved egg quality, retention of Cr and Zn, whereas, it decreased shell ratio in the 60th day eggs [58]. Nano-Cr supplementation at 0.4 mg/kg of feed also improved egg quality parameters including Cr and Zn content in eggshell, Ca in the liver and eggshell, and Zn in egg yolk [59]. Another study specified that eggs of birds supplemented with nano-Cr at 0.2 and 0.4 mg/kg feed exhibited higher shell strength than eggs of hens from the group control and receiving Cr in an inorganic form [97]. In ovo supplementation of nano-Fe though improved body weight gain to egg ratio and feed conversions ratio at 7 days of age in broiler chicks, but no such improvement was observed later and there was no significant effect on hematological parameters [98]. L-cysteine-coated Fe-oxide NP at 6 or 60 mg/kg diet improved availability and utilization of Fe as evident from increased percentage of egg production and egg weight in quails [99]. Taken together, nano-minerals can improve egg production and s eggs quality traits at decreased rate of application.
