This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This study was performed on 36 (average weight 7.6 kg) weaning piglets. The weaning piglets were randomly allocated to 1 of 4 homogeneous treatments (A, control treatment, no added Se; B, Sodium selenite, 0.3 mg Se/kg feed; C, yeast Se, 0.3 mg Se/kg; D, DL-methionine Se 0.3 mg Se/kg). Every treatment had 3 replicates, every replicate had 3 piglets. The experiment lasted for 35 d, with the first 7 d for adaptation. Feed intake, residual and contaminated feed were recorded every day. Every piglet weight was weighted respectively at beginning and end of experiment. Daily intake, gain weight and feed conversion rates of every replicate were calculated finally. Se concentrations of serum, blood antioxidant and immunity index were analyzed in the 36th d of experiment. The results showed average daily gain of treatment C was significant higher ( <i> P </i> < 0.05) and D had higher trend than that of treatment A and B ( <i> P </i> = 0.06) respectively. And feed and gain ratio of C and D had trends to lower than them of A and B ( <i> P </i> = 0.14). However, all the intake of every week and whole period had no significant differences among treatments ( <i> P </i> > 0.05). At same time, except for the Immunoglobulin M of treatment D and C was higher than that of treatment A and B significantly ( <i> P </i> < 0.05), all the other Se contents of serum, immunity indexes, blood cell parameters and enzymatic activities had no significant differences among treatments ( <i> P </i> > 0.05). But they took on some obvious trends. For example, the Se contents and glutathione peroxidase activities increased successively in order of treatment A, B, C and D; the blood urea nitrogen and total bilirubin of treatment A had higher trend than that of other treatments ( <i> P </i> = 0.06). All in all, adding to organic Se in basal diets could improve the animal’s healthy levels, growth properties and Se utilization to some extent. Relatively speaking, the DL-methionine Se had more advantages compared to yeast Se.
Selenium (Se) is an essential trace element for human and animal health, which has effects on anticancer, antioxidant, anti-cardiovascular diseases, strengthening antioxidant and immunity capacity, promoting growth and improving meat qualities, and so on [
The 36 (average weight 7.6 kg) weaning piglets (weaned on d 28) were randomly allocated to 1 of 4 homogeneous treatments (A, control treatment, no added Se; B, SS, 0.3 mg Se/kg feed; yeast Se, 0.3 mg Se/kg; DL-methionine Se 0.3 mg Se/kg). SS, yeast Se and DL-methionine Se were added to the basal diets at the expense of premix. Every treatment had 3 replicates, every replicate had 3 piglets
The experiment lasted for 35 d, with the first 7 d for adaptation. The SS was bought from Guangxi Nanning Jun Wei: Feed Co., LTD, and its content is 1000 mg/kg in product. The yeast Se and DL-methionine Se were bought respectively from Le Fu yeast companies in the Unites States and Puno (Chengdu) biological technology co., LTD, and their contents are 2000 mg/kg in product. The piglets of every group was closed in a house with access to water and feed ad libitum. During the course of experiment, all the experiment houses were well ventilated and dried, and kept temperature 25˚C - 28˚C and relative humidity 55% - 70%. Furthermore, the experiment houses were swept and fumigated twice at am 8:00 and pm 14:00 every day.
The formula and nutrient levels of the experiment diet are presented in
Ingredients | % |
---|---|
Corn | 66.3 |
Peeled soybean meal | 21.6 |
Whey power | 4.9 |
Imported fish meal | 2.9 |
CaHPO4 | 0.8 |
Limestone | 0.8 |
Soybean oil | 0.7 |
Lysine | 0.4 |
Acidifiers | 0.3 |
NaCl | 0.2 |
DL-Methionine | 0.1 |
Threonine | 0.1 |
Premix | 0.9 |
In total1 | 100 |
Nutrient levels | % |
Digestive energy (MJ/kg, DM) | 14.0 |
Crude protein2 | 18.5 |
Calcium2 | 0.75 |
Phosphorus2 | 0.60 |
Lysine | 1.30 |
L-Methionine | 0.45 |
Threonine | 0.80 |
Note: 1Provided per kilogram of diet: vitamin A 11,000 IU, vitamin D3 1500 IU, vitamin E 44.1 IU, vitamin K3 4.0 mg, vitamin B1 1.4 mg, vitamin B2 5.22 mg, vitamin B5 20.0 mg, vitamin B12 0.01 mg, niacin 26.0 mg, pantothenic acid 14 mg, folic acid 0.8 mg, biotin 44 μg, Fe 100.0 mg, Cu 16.50 mg, Zn 90.0 mg, Mn 35.0 mg, I 0.30 mg. 2Crude proteins, Calcium, Phosphorus were measured. The Se content of basal diet was 0.04 mg/kg DM. Other values were calculated based on data from the diet supplier.
The basal diets and premix were all prepared according to the People’s Republic of China feed standard in piglets (2004) by Henan Hyrum Feed Co., LED. And the feeds were offered 4 times per day, respectively 8:00am, 12:00am, 16:00pm, 20:00pm. All ingredients were same except for Se sources in four diets.
Intake, residual and contaminated feed were recorded every day. Every piglet weight gain was weighted respectively at beginning and end of experiment. Daily intake, weight gain and feed and gain ratios of every replicate were calculated finally.
Before intake and water in the morning, the 5 ml blood samples (2 ml anti-clotting and 3ml no anti-clotting) were collected from the front cavity vein of piglets among 4 treatments (one piglet/treatment replicate) in the 36th d of experiment. The collected 2 ml anti-clotting blood then centrifuged at 4000 rpm for 10 min at 4˚C to collect serum, which was frozen at −20˚C until analyzed. Serum samples were later thawed and analyzed for quantification of glutathione peroxidase (GSH-px), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), alkaline phosphatise (ALP), total protein (TP), albumin (ALB), blood urea nitrogen (BUN), creatinine (CREA), glucose (GLU), total bilirubin (TBIL), cholesterol (CHOL), immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM) were determined according to method described in other studies [
Another 3 ml no anti-clotting blood was placed into a 10-mL tube for whole blood variable determination immediately. The whole blood samples were used to determine red blood cell count (RBC), haematocrit concentration (HCT), haemoglobin concentration (HGB), and white blood cell count (WBC), platelet (PLT) according to method reported previously [
Additionally, the Se concentration of serum was determined by a SpectorAA-30 atomic absorption spectrophotometer (Varian Techtron. Pty. Ltd., Mulgrave, Victoria, Australia).
Statistical analysis was conducted using SAS 9.1.3. All data were analyzed using the MIXED procedure. Piglets within treatment were subjected as random to test for main effects and interactions using the covariance type AR (1), and the residual error was used to test for week and week × treatment interaction. Mean comparisons across treatments were made when the interaction terms of the model were significant (P < 0.05) using LSMEANS and PDIFF separation of all the treatments. Significant differences were declared at P < 0.05 and trends at 0.05 ≤ P ≤ 0.10.
The effects of organic Se on growth properties were shown in
Controls | The first week intake (g) | The second week intake (g) | The third week intake (g) | The fourth week intake (g) | The whole period intake (g) | Average daily gain (g) | Feed and gain ratio (F/G) |
---|---|---|---|---|---|---|---|
A (n = 3) | 464 ± 59 | 631 ± 46 | 772 ± 30 | 876 ± 41 | 686 ± 163 | 321b ± 40 | 2.14 ± 0.12 |
B (n = 3) | 456 ± 34 | 636 ± 55 | 769 ± 28 | 870 ± 49 | 683 ± 162 | 314b ± 63 | 2.20 ± 0.28 |
C (n = 3) | 476 ± 32 | 645 ± 49 | 770 ± 27 | 870 ± 46 | 690 ± 154 | 419a ± 128 | 1.72 ± 0.34 |
D (n = 3) | 492 ± 34 | 652 ± 38 | 761 ± 27 | 877 ± 51 | 695 ± 149 | 385ab ± 116 | 1.82 ± 0.27 |
Note: In the same column, values with different capital and small letters mean very significant difference at P < 0.01 and significant difference at P < 0.05.
know that average daily gain of treatment C was significant higher (P < 0.05) and D had higher trend than that of treatment A and B (P = 0.06) respectively. And feed and gain ratio of C and D had trends to lower than them of A and B (P = 0.14). However, all the intake of every week and whole period had no significant differences among treatments (P > 0.05).
The effects of organic Se on Se contents in serum, immunity indexes, blood cell and biochemistry parameters were shown in Tables 3-6. Except for the IgM of treatment D and C was higher than them of treatment A and B significant (P < 0.05), all the other Se contents of serum, immunity indexes, blood cell parameters and enzymatic activities had no significant differences among treatments (P > 0.05). But they took on some obvious trends. For example, the Se contents and GSH-Px activities increased successively in order of treatment A, B, C and D; the BUN and TBIL of treatment A had higher trend than them of other treatments (P = 0.06).
The effects of Se on growth performance of animals are somewhat variable. It was reported that different Se sources and levels did not effect on the average daily gain weight, intake and feed and meat ratio among the groups [
Controls | Se in serum (mg/kg) | IgA (g/L) | IgG (g/L) | IgM (g/L) |
---|---|---|---|---|
A (n = 3) | 0.12 ± 0.02 | 0.06 ± 0.02 | 3.69 ± 0.81 | 0.74b ± 0.26 |
B (n = 3) | 0.13 ± 0.03 | 0.03 ± 0.01 | 4.11 ± 0.45 | 0.62b ± 0.25 |
C (n = 3) | 0.13 ± 0.01 | 0.04 ± 0.02 | 4.58 ± 1.05 | 1.04a ± 0.31 |
D (n = 3) | 0.17 ± 0.06 | 0.10 ± 0.14 | 4.44 ± 0.91 | 1.30a ± 0.20 |
1) In the same column, values with different capital and small letters mean very significant difference at P < 0.01 and significant difference at P < 0.05. 2) IgA, Immunoglobulin A; IgG, Immunoglobulin G; IgM, Immunoglobulin M.
Controls | RBC (quantities × 1012/L) | WBC (quantities × 1010/L) | PLT (quantities × 1011/L) | HGB (g/L) | HCT (%) |
---|---|---|---|---|---|
A (n = 3) | 6.91 ± 0.79 | 2.84 ± 0.59 | 1.38 ± 0.53 | 111 ± 11 | 41.4 ± 3.7 |
B (n = 3) | 6.72 ± 0.76 | 3.57 ± 0.64 | 3.00 ± 0.97 | 102 ± 14 | 38.2 ± 5.3 |
C (n = 3) | 6.54 ± 0.59 | 2.27 ± 0.35 | 3.34 ± 1.76 | 107 ± 13 | 39.6 ± 4.5 |
D (n = 3) | 6.27 ± 0.88 | 3.16 ± 0.82 | 2.59 ± 0.51 | 100 ± 12 | 37.6 ± 3.8 |
RBC, red blood cell count; WBC, white blood cell count; PLT, platelet; HGB, haemoglobin concentration; HCT, haematocrit concentration.
Controls | TP (g/L) | ALB (g/L) | BUN (m mol/L) | CREA (u mol/) | GLU (m mol/L) | CHOL (m mol/L) | TBIL (u mol/L) |
---|---|---|---|---|---|---|---|
A (n = 3) | 53.9 ± 7.0 | 25.6 ± 2.9 | 5.52 ± 1.48 | 119 ± 22 | 2.42 ± 1.61 | 3.63 ± 0.97 | 3.20 ± 3.07 |
B (n = 3) | 56.3 ± 4.4 | 24.0 ± 2.4 | 3.65 ± 0.60 | 96 ± 13 | 1.84 ± 1.25 | 2.41 ± 0.32 | 0.43 ± 0.17 |
C (n = 3) | 50.5 ± 3.8 | 25.5 ± 5.9 | 4.24 ± 0.18 | 203 ± 198 | 2.27 ± 0.84 | 2.74 ± 0.40 | 0.35 ± 0.13 |
D (n = 3) | 55.5 ± 8.4 | 22.9 ± 6.0 | 4.94 ± 0.39 | 99 ± 16 | 1.75 ± 0.72 | 3.70 ± 1.83 | 0.40 ± 0.19 |
TP, total protein; ALB, albumin; BUN, blood urea nitrogen, CREA, creatinine; GLU, glucose; CHOL, cholesterol; TBIL, total bilirubin.
Controls | GSH-PX Activities (U/ml) | ALT (U/L) | AST (U/L) | GGT (U/L) | ALP (U/L) |
---|---|---|---|---|---|
A (n = 3) | 550 ± 105 | 59.8 ± 18.0 | 101 ± 21 | 150 ± 61 | 153 ± 62 |
B (n = 3) | 588 ± 85 | 81.0 ± 15.3 | 117 ± 22 | 275 ± 38 | 239 ± 105 |
C (n = 3) | 622 ± 76 | 69.3 ± 20.4 | 77 ± 25 | 246 ± 17 | 311 ± 120 |
D (n = 3) | 683 ± 91 | 64.0 ± 15.3 | 114 ± 26 | 354 ± 48 | 176 ± 22 |
GSH-PX, glutathione peroxidase; ALT, alanine aminotransferase; AST, aspartate amino transferase; GGT, gamma-glutamyltransferase; ALP, alkaline phosphatise.
growth performance. The underlying mechanism might be they elevated health levels of animals and thus improved the growth performance of weaning piglets [
Mahan and Peters (2004) reported that organic Se showed a higher potential to improve the Se status in the piglets [
The research showed the RBC increasing in quantities might promote the WBC phagocytic functions, improve the body’s ability to deliver oxygen in blood, strengthen immunity and metabolic functions. However, the WBC, neutrophils and lymphocyte are the important indexes indicated immunity of animal bodies, and the changes of quantities are the stronger or weaker expression of cell [
The changes of blood biochemistry parameters are the reflex of permeability changes of tissue and cell and metabolism function changes of bodies. ALT exists in cytoplasm of dogs, cats and primates mainly and so on, and it is one of the most sensitive liver function test index of the animals. The AST contents are higher in liver cells, hearts and skeletal muscles and they can be used to explore the extensive organizational damages. Normally the AST increasing of cattle and goats often occurs in hepatic necrosis symptoms caused by all kinds of reasons [
Se is active ingredient of GSH-PX. However the GSH-PX activity determination in plasma of piglets is the important indexes of measuring Se levels and antioxidant capacity of animal bodies. It is widely accepted that proper Se intake improved the antioxidant status of the body in any form of Se. In general, organic Se-enriched yeast showed more potential to improve the antioxidant status than inorganic Se [
In this experiment, the enzymatic activities had no significant differences among treatments (P > 0.05), but the GSH-Px activities increased successively in order of treatment A, B, C and D. It showed adding organic Se could improve the GSH-Px activities and body’s antioxidant capacity. On the other hand, the GSH-Px activities of DL-selenomethionine were the highest among all treatments which showed DL-selenomethionine had more advantages compared to yeast Se. This was consistent with the other results.
In this experiment, adding to organic Se had improved the animal’s healthy level, growth properties, Se utilization and antioxidant capacity to some extent. Relatively speaking, DL-methionine Se had more advantages in all kinds of ways. We suggested that organic Se, especially DL-selenomethionine, exhibited higher absorption and utilization efficiency, better antioxidant capacity than SS and could provide as an effective additive for weaning piglets to improve its growth performance. Hence, DL-selenomethionine, a pure organic Se source, would have bright implication in feed additives of the weaning piglets industry.
This work was supported by Henan Provincial Department of International Technical Cooperation Foundation (Project #162102410028) and the key Projects of Scientific and Technological Research in the Department of Education of Henan Province (Zhengzhou, China; No. 14B230019), and the Chair Programs Fund from the Henan Key Lab of Unconventional Feed Resources Innovation and Utilization. Here we are also grateful to the technical staffs of experimental center and testing center in the Henan Key Lab of Unconventional Feed Resources Innovation and Utilization for their help in this work. Also, staff members of Chuying agricultural and animal husbandry limited company, Weishi branch office (Kaifeng, China) are appreciated for their care for the experimental weaning piglets used in this study.
The authors declare no conflicts of interest regarding the publication of this paper.
Zhang, W.X., Li, Y., Deng, H.Y., Li, Z., Xiang, R.P., Guo, J.L. and Pan, C.M. (2020) Effects of Organic Selenium on Growth Properties, Selenium Absorption and Utilization, Antioxidant Activity and Immunity in Weaning Piglets. Food and Nutrition Sciences, 11, 385-395. https://doi.org/10.4236/fns.2020.115028