Effects of Dietary Iodine and Selenium on Nutrient Digestibility,Serum Thyroid Hormones,and Antioxidant Status of Liaoning Cashmere Goats

Forty-eight 2-year-old Liaoning Cashmere goats (body weight = 38.0 ± 2.94 kg) were used to investigate the effects of dietary iodine (I) and selenium (Se) supplementation on nutrient digestibility, serum thyroid hormones, and antioxidant status during the cashmere telogen period to learn more about the effects of dietary I and Se on nutrition or health status of Cashmere goats. The goats were equally divided into six groups of eight animals each that were treated with 0, 2, or 4 mg of supplemental I/kg dry matter (DM) and 0 or 1 mg of supplemental Se/kg DM in a 2 × 3 factorial arrangement of treatments. The six treatments were I₀Se₀, I₂Se₀, I₄Se₀, I₀Se₁, I₂Se₁, and I₄Se₁. The concentrations of I and Se in the basal diet were 0.67 and 0.09 mg/kg DM, respectively. The study started in March and proceeded for 45 days. Supplemental I or Se alone had no effect on nutrient digestibility and nitrogen metabolism. However, the interaction between I and Se was significant regarding the digestibility of acid detergent fiber (ADF; P < 0.05), and compared with group I₄Se₁, the digestibility of ADF was significantly increased in group I₄Se₀ (P < 0.05). Selenium supplementation did not affect serum triiodothyronine (T₃) or thyroxine (T₄) concentrations. However, the concentration of serum T₄ but not that of T₃ was significantly increased with I supplementation (P < 0.05). In addition, serum superoxide dismutase (SOD) activity was not affected (P > 0.05), but serum glutathione peroxidase (GSH-Px) activity was significantly decreased by I supplementation (P < 0.05). The antioxidant status was improved by Se supplementation, and the activities of SOD and GSH-Px were significantly increased (P < 0.05).     

Use of Clonostachys rosea against sheep nematodes developing in pastures

The fungus Clonostachys rosea f. rosea has the potential to control gastrointestinal nematodes (GIN) of sheep. A study was conducted using adult Merino sheep. Gender, egg count and initial body weights (BWs) were used to categorise animals into four groups which were randomly assigned to one of four C. rosea dietary treatments. Treatments were mixed with a complete diet and fed to sheep once daily for 10 weeks. There was no effect of treatment on eggs per gram of faeces. However, treatments reduced the number of larvae per gram in faecal cultures (P < 0.001) and larval development (LD) time (P < 0.001). Efficacy of treatments increased (P < 0.001) with time. On Day 70, treatments of 0.25, 0.5 and 1.0 g of C. rosea chlamydospores per kilogram BW reduced LD time by 33, 72 and 89%, respectively, whereas in the control, LD was reduced by only 2.6%. C. rosea significantly (P < 0.001) reduced numbers of third-stage larvae (L₃) found in pastures. Our findings suggest that daily feeding with C. rosea has a potential to reduce larval stages of GIN in pastures.     

Effects of different selenium sources on tissue selenium concentrations,blood GSH-Px activities and plasma interleukin levels in finishing lambs

Thirty-two wether lambs of Tan sheep were randomly assigned into four dietary treatment groups (eight per group) for an 8-wk study and then fed a basal diet deficient in Se (0.06 mg/kg) or diets supplemented to provide 0.10 mg/kg Se from sodium selenite, selenized yeast, and selenium-enriched probiotics, respectively. Blood samples were collected at d 0, 28, and 56 of the experiment and tissue samples were collected at experiment termination. Tissue and blood Se concentrations, blood glutathione peroxidase (GSH-Px) activities, and plasma interleukin levels were analyzed. The results showed that the concentrations of Se in the kidney, liver, and muscle increased in all of the supplemented groups (p<0.01) compared with the control group. However, the Se concentrations in the kidney, liver, and muscle in the groups supplemented with Se yeast and Se-enriched probiotics were higher than those in the group supplemented with sodium selenite (p<0.01). The activities of GSH-Px and the concentrations of Se in blood also increased in all of the supplemented groups during the period of supplementation (p<0.01) compared with the control group. The activities of GSH-Px and the concentrations of Se in the whole blood of the lambs fed with selenized yeast and Se-enriched probiotics were higher than those of lambs fed with sodium selenite (p<0.01 or p<0.05). The concentrations of interleukin-1 and interleukin-2 in plasma significantly increased in all of the supplemented groups during the entire period of experiment (p<0.01) compared with the control group, but had no significant differences among all of the supplemented groups. In conclusion, a diet supplemented with Se for finishing lambs was able to increase the concentrations of Se in tissue and blood, activities of GSH-Px in blood, and levels of interleukins in plasma. Organic Se sources (selenized yeast and Se-enriched probiotics) were more effective than the inorganic Se source (sodium selenite) in increasing tissue and blood Se concentrations and blood GSH-Px activities of lambs. However, there were no significant differences in plasma interleukin levels of lambs between organic and inorganic Se sources.     

Protective role of intraperitoneally administered vitamin E and selenium on the antioxidative defense mechanisms in rats with diabetes induced by streptozotocin

The aim of this work was to determine the protective effects of intraperitoneally administered vitamin E and selenium (as Na₂SeO₃, Se) on the lipid peroxidation as thiobarbituric acid reactive substances (TBARS) and vitamin E levels, glutathione peroxidase (GSH-Px), reduced glutathione (GSH) activities in the plasma, red blood cell (RBC), liver, and muscle of rats with streptozotocin-induced diabetes. Fifty adult male Wistar rats were used and all rats were randomly divided into five groups. The first group was used as a control and the second group as a diabetic control. A placebo was given to first and second groups by injection. The third group was intraperitoneally administered with vitamin E (20 mg over 24 h), the fourth group with Se (0.3 mg over 24 h), and the fifth group with vitamin E and Se combination (COM) (20 mg vitamin E + 0.3 mg Se over 24 h). This administration was done for 25 days and the TBARS, vitamin E, GSH-Px, GSH levels in the plasma, RBC, liver, and muscle samples were determined. The vitamin E level in the plasma and liver was significantly (p < 0.05) higher in the control than in the diabetic control group. Also, the TBARS levels in the RBC, liver, and muscle were significantly (p < 0.05) lower in the control than in the diabetic control group. However, GSH-Px and GSH activities in RBC, liver, and muscle were not statistically different between the control and the diabetic control groups. The vitamin E levels in plasma and liver (p < 0.01 and p < 0.001) and GSH-Px activities (p < 0.01, p < 0.001) in RBC were significantly higher in vitamin E, Se, and COM groups than in both control and diabetic control groups. However, the TBARS levels of RBC, muscle, and liver in vitamin E and Se administered groups were significantly (p < 0.05-p < 0.001, respectively) decreased. These results indicate that intraperitoneally administered vitamin E and Se have significant protective effects on the blood, liver, and muscle against oxidative damage of diabetes. The abstract of this study was presented in Physiological Research 48(Suppl. 1), S99 (1999).     

Effects of Nigella sativa L. and Urtica dioica L. on selected mineral status and hematological values in CCl4-treated rats

This study was designed to investigate the effects of Nigella sativa L. (NS), known as black seed, or/and Urtica dioica L. (UD), known as stinging nettle root, treatments on serum Na, K, Cl, and Ca levels and some hematological values of CCl₄-treated rats. Sixty healthy male Sprague-Dawley rats, weighing 250–300 g, were randomly allotted into 1 of 4 experimental groups: A (CCl₄-only treated), B (CCl₄+UD treated), C (CCl₄+NS treated), and D (CCl₄+UD+NS treated), each containing 15 animals. All groups received CCl₄ (0.8 mL/kg of body weight, subcutaneously, twice a week for 90 d starting d 1). In addition, B, C, and D groups also received the daily ip injection of 0.2 mL/kg NS and/or 2 mL/kg UD oils for 45 d starting d 46. Group A, on the other hand, received only 2 mL/kg normal saline solution for 45 d starting d 46. Blood samples for the biochemical analysis were taken by cardiac puncture from five randomly chosen rats in each treatment group at the beginning, d 45, and d 90 of the experiment. The CCl₄ treatment for 45 d significantly (p<0.05) increased the serum K and Ca and decreased (p<0.05) the red blood cell count (RBC), white blood cell count (WBC), packed cell volume (PCV), and Hb levels without changing (p>0.05) the serum Na and Cl levels. NS or UD treatments (alone or combination) for 45 d starting d 46 significantly (p<0.05) decreased the elevated serum K and Ca levels and also increased (p<0.05) the reduced RBC, WBC, PCV, and Hb levels. It is concluded that NS and/or UD treatments might ameliorate the CCl₄-induced disturbances of anemia, some minerals, and body’s defense mechanism in CCl₄-treated rats.     

Differential Effects of Sodium Selenite and Nano-Se on Growth Performance,Tissue Se Distribution,and Glutathione Peroxidase Activity of Avian Broiler

The present research evaluated differential effects of sodium selenite and nano-Se on growth performance, tissue Se distribution, and glutathione peroxidase (GSH-Px) activity of avian broiler. Broilers were randomly segregated into 12 groups so that three replicates were available for each of the three treatments (T-1, T-2, and T-3) and control groups. The control groups were fed basal diets without Se addition. T-1, T-2, and T-3 were fed with diets containing 0.2 mg kg⁻¹ sodium selenite, 0.2 mg kg⁻¹ nano-Se, and 0.5 mg kg⁻¹ nano-Se, respectively. Compared with the control, Se supplementation remarkably improved daily weight gain and survival rate and decreased feed conversion ratio (P < 0.05). However, no significant difference was observed between T-1, T-2, and T-3. The tissue Se content was significantly higher (P < 0.05) in Se-supplemented groups than the control, and T-3 showed the highest. Furthermore, higher Se content was observed in liver, and there was a significant difference (P < 0.05) compared with that in muscle. As for serum and hepatic GSH-Px activities, Se supplementation remarkably improved GSH-Px activity (P < 0.05), and there was no significant difference (P > 0.05) between treatments (T-1, T-2, and T-3).     

Effect of selenium supplementation on thyroid hormone levels and selenoenzyme activities in growing lambs

The aim of the present study was to evaluate the effects of selenium supplementation on thyroid hormone metabolism and selenoenzyme activities in lambs. Twelve 20-d-old male lambs were assigned to one of two diets: A (0.11 ppm Se) and B (supplemented with 0.2 ppm selenium as sodium selenite). Blood samples were collected weekly for the determination of T₃, T₄, and selenium levels. The response to thyrotropin-releasing hormone (TRH) challenge was estimated at the 11th and 20th wk. Animals were slaughtered at wk 20 and tissues were collected for enzyme determination. Plasma selenium concentration was significantly higher in supplemented lambs (p<0.001). Plasma T₃ and T₄ levels remained similar in both groups. Type I deiodinase activity (ID-I) was decreased in the liver (p<0.05) and increased in the pituitary (p<0.01) of supplemented animals. No ID-I activity was detected in the thyroid. Pituitary type II deiodinase activity (ID-II) remained unchanged. The response to TRH challenge did not differ between the two groups for both challenges, but in group B, the second TRH challenge (20th wk) resulted in a significantly higher T₃ response compared to the first one (11th wk) (p<0.05). In conclusion, the lack of effects of Se supplementation on thyroid hormone metabolism demonstrates that enzyme activity is homeostatically controlled and selenium is incorporated in that order to ensure the maintenance of thyroid hormone homeostasis.     

Selenomethionine: an Effective Selenium Source for Sow to Improve Se Distribution,Antioxidant Status,and Growth Performance of Pig Offspring

The present study was to investigate the efficiency of maternal selenomethionine intake on growth performance, Se distribution, and antioxidant status of pig offspring by comparing with sodium selenite. A total of 12 sows (Landrace × Yorkshire) with same pregnancy were randomly divided into two groups; each group was replicated six times. These two groups received the same basal gestation and lactation diets containing 0.04 mg Se/kg, supplemented with 0.3 mg Se/kg sodium selenite and selenomethionine (i.e., seneno-dl-methylseleno), respectively. The feeding trial lasted for 60 days, with 32 and 28 days for gestation and lactation period, respectively. Compared with sodium selenite, maternal selenomethionine intake significantly (p < 0.05) increased the daily weight gain of piglet from birth to weaning. The Se concentration in the colostrum and milk and tissue Se content of piglets were significantly higher (p < 0.05) in the selenomethionine-treated group. The antioxidant status was greatly improved in piglets of selenomethionine-treated group and was illuminated by the increased total antioxidant capability, glutathione peroxidase, superoxide dismutase, and glutathione, and decreased the malondialdehyde level in the organs of piglets. The increased (p < 0.05) triiodothyronine (T₃) and decreased (p < 0.05) thyroxine (T₄) concentration indicated the improved protein synthesis and energy production in the selenomethionine-treated group. The increased (p < 0.05) pancreatic digestive enzymes of protease, amylase, and lipase activities indicated that maternal selenomethionine intake may have a positive effect on the degradation and absorption of nutrients in its piglets. In summary, we concluded that maternal selenomethionine intake increased Se deposition, antioxidant status, and nutrient use efficiency, thus providing an effective way to improve the growth performance of piglets from birth to weaning.     

Adaptive responses to fescue toxicosis under thermoneutral and heat stress conditions

This study determined the potential for short-term adaptation to fescue toxicosis and heat stress in rats. Male CD outbred rats (n=24) were implanted with temperature transmitters (Respironics, Bend, OR) to measure core temperature (Tc) and general activity. All rats were initially fed diets with ground, uninfected tall fescue seed (E−) and exposed to 21 °C (thermoneutral, TN) to establish baseline values. In Period 1, all groups were maintained at TN for 7 days, with one group fed a diet containing ground, endophyte-infected tall fescue seed (E+, approximately 165 μg ergovaline/kg BW/d) and two groups fed E− diet. Ergovaline is thought to be the primary toxin responsible for many symptoms associated with fescue toxicosis. Period 1 was followed by 7 days at 31 °C (heat stress, HS, Period 2) on the same diets. All animals were fed E− diet during the second 7 day of HS (Period 3). In the final 7 day (Period 4), E+ diet was returned to the original group and fed to one of the previously E− groups, with the third group remaining on E− diet. A 40% decrease in FI occurred with E+ treatment at TN (P<0.05), with a comparable BW reduction (P<0.05) after 4 day. Both responses worsened during HS. Treatment with E+ in Period 4 indicated that FI and BW had not adapted to fescue toxicosis. A reduction in daily Tc occurred with E+ treatment at TN (P<0.05) followed by hyperthermia during the initial stage of HS (P<0.05). Although feed intake and growth rate showed no change over time, there was a reduction in fescue toxicosis-induced hyperthermia in the heat with repeat treatment. Conditioning animals to fescue toxicosis and heat stress prior to exposure may be beneficial in reducing impacts on thermal status of the animal.     

Selenium-methionine and chromium-methionine supplementation of sheep around parturition: impacts on dam and offspring performance

To examine the effects of maternal energy restriction along with selenium-methionine (Se-Met) and chromium-methionine (Cr-Met) supplementation on performance of pregnant sheep and their offspring, the following treatments were allotted randomly to 40 multiparous Baluchi ewes (53.9 ± 1.15 kg of body weight [BW]) from 5 weeks prior to 5 weeks after parturition: (1) Control diet (60% and 100% of NRC energy requirements in pre- and post-partum, respectively); (2) Control diet plus 5 mg Se-Met/kg dry matter (DM); (3) Control diet plus 3 mg Cr-Met/kg DM and (4) Control diet plus 5 mg Se-Met and 3 mg Cr-Met/kg DM (Se–Cr-Met) of concentrate diet. The results indicated that Cr-Met alone or in combination with Se-Met increased average DM intake of ewes. In addition, Group Cr-Met had higher average BW than the Control (p < 0.05). Se-Met and/or Cr-Met supplementation led to decreased average serum cholesterol of the ewes (p < 0.05). Groups Cr-Met and Se–Cr-Met displayed decreased average serum malondialdehyde compared to the Control (p < 0.05). At 24 h post-partum, Group Se–Cr-Met had a greater serum Se content than the Control (p = 0.006). Compared with the Control, the Se concentration in milk was significantly increased from 30 to 138 µg/l and 197 µg/l in Groups Se-Met and Se–Cr-Met, respectively (p < 0.01), which proved that Se-Met supplementation can increase the Se concentration of ewe milk. Furthermore, feeding Cr-Met may attenuate BW loss post-partum and Se-Met and/or Cr-Met supplements may ameliorate oxidative stress condition in ewes around parturition.     

Effect of Boron as an Antidote on Dry Matter Intake,Nutrient Utilization and Fluorine Balance in Buffalo (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>) Exposed to High Fluoride Ration

Twenty male buffalo calves (8–9 months, 112.1 ± 7.69 kg) were divided into four groups of five animals in each and fed diets without (T1) or supplemented with 0.3 ppm selenium (Se) (T2), 0.3 ppm Se + 10 ppm copper (Cu) (T3), and 10 ppm Cu (T4) for 120 days during which blood samples were collected on day 0, 40, 80, and 120. Concentrations of glucose, total protein, urea, uric acid, and creatinine were similar in all the four groups, but the level of globulin was significantly (P < 0.01) increased in groups T2 and T3, leading to reduced levels of albumin and A:G ratio (P < 0.01) in these groups. The level of different serum enzymes viz. lactate dehydrogenase (LDH), alkaline phosphatase (ALP), glutamate pyruvate transaminase (SGPT), and glutamate oxaloacetate transaminase (SGOT) and hormones viz. T₃, T₄, testosterone and insulin and T₄:T₃ ratio were similar (P > 0.05) among the four groups. It was deduced that supplementation of 0.3 ppm Se and/or 10.0 ppm of Cu had no effect on blood metabolic profile in buffalo calves, except for an increased globulin level, indicating improved immunity status of these animals.     

Effects of chronic fluorosis on electrocardiogram in sheep

This study was carried out to evaluate the effects of chronic fluorosis by means of the electrocardiograms in sheep. Ten sheep with fluorosis living around a volcanic mountain (Tendürek Mount) in East Anatolia in Turkey and 10 healthy sheep were used. Leads I, II, III, aVR, aVL, aVF, V₂, V₄, and V₁₀ were recorded in the electrocardiographs of the sheep. All waves were seen in all derivations. The P-Q interval was significantly (p<0.05) prolonged and sinus bradycardia was observed in the sheep with fluorosis. As a result of this, the number of heart beats was decreased significantly (p<0.05); that is, the number of heart beats was 110±15 in the control group and 75±10 in sheep with fluorosis.     

Protective role of intraperitoneally administrated vitamin E and selenium on the levels of total lipid,total cholesterol,and fatty acid composition of muscle and liver tissues in rats

The aim of this work was to determine the protective effects of intraperitoneally administrated vitamin E and Se on total lipid, total cholesterol, and fatty acid composition of rat liver and muscle tissues. Total lipid content of muscle tissue in Se and combination groups decreased as compared to the control group. However, the level of total lipid in the liver tissues was seen to decrease only in the combination group (P < 0.05). While the amount of total cholesterol in liver tissue was lower (P < 0.05) in the vitamin E and combination groups, the amount of total cholesterol in muscle tissue decreased (P < 0.05) in the combination group. The amount of linoleic acid in muscle tissue slightly decreased (P < 0.05), whereas the eicosenoic and eicosatrienoic acid amounts significantly increased (P < 0.01, P < 0.001) in the vitamin E group as compared to the control group. The amounts of most fatty acid decreased (P < 0.05) in the combination group. The proportions of eicosenoic, eicosatrienoic, and total polyunsaturated fatty acid (PUFA) within the total fatty acid were higher (P < 0.05) in vitamin E group, whereas these fatty acids proportions were lower (P < 0.05) in the Se group. Although the proportions of palmitic, linolenic, and total saturated fatty acids were low (P < 0.05), oleic and total unsaturated fatty acid proportions were higher (P < 0.05) in the combination group than in the control group. The amount of palmitic acid and total saturated fatty acid in liver tissue decreased (P < 0.01 and P < 0.05, respectively) in the vitamin E and combination groups. However, the amount of linoleic acid only decreased (P < 0.05) in the combination group. The amount of PUFA was slightly higher (P < 0.05) in vitamin E. The proportions of stearic acid and linoleic acid decreased (P < 0.05) both in the Se and combination groups. However, the proportions of eicosatrienoic, ω 6, and PUFA were slightly higher (P < 0.05) in the vitamin E group, but total saturated fatty acid proportion significantly decreased (P < 0.01) in both the vitamin E and combination groups. In conclusion, the level of total lipid and cholesterol in muscle and liver tissues were reduced by administrating vitamin E and Se together. Additionally, the fatty acid synthesis in the muscle and liver tissues was decreased by this process. However, it was observed that the protective effect of intraperitoneally administrated vitamin E was higher than Se on fatty acid composition in muscle and liver tissues. J. Cell. Biochem. 64:233–241. © 1997 Wiley-Liss, Inc.     

Effect of black cumin (Nigella sativa) on cadmium-induced oxidative stress in the blood of rats

The protective effect of black cumin (Nigella sativa=NS) on cadmium-induced oxidative stress was studied in rats. The rats were randomly divided into three experimental groups: A (conrol), B (Cd treated), and C (Cd+NS treated), each containing 10 animals. The Cd-treated and Cd+NS-treated groups were injected subcutaneously daily with CdCl₂ dissolved in isotonic NaCl in the amount of 2 mL/kg for 30 d, resulting in a dosage of 0.49 mg Cd/kg/d. The control group was injected with only isotonic NaCl (2 mL/kg/d) throughout the experiment (for 30 d). Three days prior to induction of CdCl₂, the Cd+NS-treated group received a daily intraperitoneal injection of 0.2 mL/kg NS until the end of the study. Cd treatment increased significantly the malondialdehyde levels in plasma and erythrocyte (p<0.01 and p<0.05, respectively) and also increased significantly the antioxidant levels (superoxide dismutase, glutathione peroxidase, and catalase) (p<0.05) compared to the control group. Cd+NS treatment decreased significantly the elevated malondialdehyde levels in plasma and erythrocyte (p<0.01 and p<0.05, respectively) and also reduced significantly the enhanced antioxidant levels (p<0.05). Cd treatment increased significantly the activity of iron levels (p<0.05) in the plasma compared to the control group. Cd+NS treatment decreased the activity of iron levels (p<0.05) in the plasma compared to the Cd-treated group. In the control group with no treatment, histology of erythrocytes was normal. In the Cd-treated group, there were remarkable membrane destruction and hemolytic changes in erythrocytes. In the Cd+NS treated group, these changes were less than in the Cd-treated group. Our results show that N. sativa exerts a protective effect against cadmium toxicity.     

Serum mineral levels at pregnancy and postpartum in single and twin pregnant sheep

This study was performed to investigate calcium (Ca), inorganic phosphorus (P), potassium (K), magnesium (Mg), and chlorine (Cl) levels in blood serum at d 60, 100, and 150 of gestation and at d 45 after parturition and to find out the significance of differences for macromineral levels during these stages of single or twin gestation in Akkaraman sheep. Blood samples of 30 apparently healthy pregnant Akkaraman sheep (15 single pregnancies, 15 twin pregnancies) were used. The samples were analyzed using a biochemical analyzer for Ca, P, Na, K, and Mg concentrations and using the Schales method for Cl levels. A statistically significant decrease (p<0.001 and p<0.05) was found on d 100 of pregnancy for Ca levels and for serum inorganic P levels in both groups. Twin pregnant sheep were found to have lower (p<0.05) serum Ca and inorganic P levels than sheep pregnant with one fetus on d 100 and 150. Significant decreases (p>0.05, p <0.01) for serum Mg levels in both groups were recorded on d 100 and 150 of pregnancy. There were significant increases (p<0.01) in serum Cl levels on d 100 in single and twin pregnant sheep.     

Effect of zinc supplementation from different sources on growth, nutrient digestibility, blood metabolic profile, and immune response of male guinea pigs

Forty weaned male guinea pigs of 208.20±6.62 g mean body weight were divided into 4 groups of 10 animals in a randomized block design. All of the guinea pigs were fed a basal diet [25% ground maize hay, 30% ground maize grain, 22% ground chickpea (Cicer arietinum L.), 9.5% deoiled rice bran, 6% soybean meal, 6% fish meal, 1.45% mineral supplement (without Zn) and 0.05% ascorbic acid] and available green fodder. Group I served as the control (no Zn supplementation), whereas 20 ppm Zn was added in the diet in groups II, III, and IV either as zinc sulfate (ZnSO₄), zinc amino acid complex (ZAAC), and ZnSO₄ ⁺ ZAAC in equal parts, respectively. Experimental feeding lasted for 70 d, including a 3-d digestibility trial. Blood was collected through cardiac puncture from four animals in each group at d 0 and subsequently at the end of experimental feeding. After 40 d of experimental feeding, four animals from each group were injected with 0.4 mL of Brucella abortus cotton strain-19 vaccine to assess the humoral immune response of the animals. After 10 wk of study, four animals from each group were sacrificed to study the concentration of Zn, Cu, Co, Fe, and Mn in the liver, pancreas and spleen. Results revealed no significant difference in the feed intake, body weight gain, and digestibility of the nutrients, except for crude protein (CP) digestibility, which was significantly (p<0.05) lower in group IV. Although concentrations of serum glucose, Ca, and P and the albumin:globulin (A:G) ratio were similar in the different groups, the total protein, albumin, and serum alkaline phosphatase activity were higher in all of the Zn-supplemented groups on d 70. The serum Zn levels at the end of experimental feeding were significantly higher in groups II and III, whereas serum Mn levels were found to be significantly (p<0.05) higher in groups III and IV. The organ weights (as percentage of body weights) did not show any differences among the treatment groups. Although the Mn concentration was significantly (p<0.05) higher in the pancreas, the Cu concentration was significantly (p<0.05) reduced in the spleen in all of the Zn-supplemented groups. The humoral immune response (antibody titer values) on d 14 of vaccination was significantly (p<0.05) higher in all of the Zn-supplemented groups. It was concluded that the 20-ppm level of Zn in the diet might be adequate for growth and nutrient utilization in guinea pigs, but supplementation of 20-ppm zinc significantly improved the immune response and impact was more prominent with the ZAAC (organic source) compared to ZnSO₄ (inorganic source).     

Wool cortisol is a better indicator of stress than blood cortisol in ewes exposed to heat stress and water restriction

This study investigated the effect of water restriction on wool and blood cortisol concentrations and water consumption patterns in heat-stressed sheep. Nine Corriedale female sheep (average BW=43±6.5 kg) were individually fed diets based on maintenance requirement in metabolic crates. They were assigned to three treatments according to a Latin square design (3×3) for three periods with a 21-day duration for each period (nine sheep per treatment). Treatments included free access to water (FAW), 2 h water restriction (2hWR) and 3 h water restriction (3hWR) after feeding. Average temperature–humidity index in the experimental room was 27.9 throughout the experiment that defines heat stress conditions. Wool samples were taken at the end of each period on day 21. No differences were found in cortisol concentration in each fragment (dried, washed and residual extract) of wool (P<0.05). Total wool cortisol concentration was higher in the 3hWR group than the other treatments (P<0.05). Blood cortisol was not different among the treatments (P>0.05) and resulted in higher variable data compared with wool cortisol. Blood neutrophils and neutrophil/lymphocyte ratio suppressed in FAW and 3hWR groups compared with the 2hWR group (P<0.05). The duration of water consumption recorded after feeding in the 3hWR group was higher than in the 2hWR group when recorded in the afternoon (P<0.01). Water consumption rate was higher in the 3hWR group than in the 2hWR group (P<0.01). However, total water consumed was lower in the 3hWR group compared with other treatments (P>0.05). It can be concluded that wool cortisol provides more precise and accurate data than blood cortisol during heat stress conditions. Water restriction for 3 h after feeding can act as a stressor and is critical for sheep during heat stress as the consumption of water decreases with restriction.     

Options for the Production of Selenized Chicken Meat

A 42-day experiment was conducted to compare the effects of various levels of sodium selenite (SS) and Se-enriched yeast (SY) on chicken productivity, carcass traits, and breast Se concentration. Six hundred 1-day-old Cobb 500 broiler chicks were placed on 1 of 6 experimental treatments. The treatments consisted of feeding a diet without Se supplementation (basal diet) or basal diet with 0.6 mg/kg supplemented Se supplied by SS, SY, or a mix of the two (0.45 SS + 0.15 SY; 0.3 SS + 0.3 SY; 0.15 SS + 0.45 SY). Chicks in all Se-supplemented treatments had significantly higher final body weight and eviscerated weight than those on the basal diet (P < 0,05) and no significant differences were observed among selenium source (P < 0.05). Also, chicks in all Se-supplemented treatments had significantly higher Se contents in breast tissue than the control group (P < 0.05). Replacing SS by SY in the broiler diets resulted in increased concentrations of Se in the breast (P < 0.01). Strong correlations were found between breast Se concentrations and the level of SY supplementation of the broiler diet (r = 0.992). The results from this experiment indicate that SY is a superior source of selenium for the production of selenized meat, and can be used, without any detrimental effect on chicken performance, for adding nutritional value to broiler meat and thus safely improving human selenium intake.     

Lead Affects Apoptosis and Related Gene <Emphasis Type="Italic">XIAP</Emphasis> and <Emphasis Type="Italic">Smac</Emphasis> Expression in the Hippocampus of Developing Rats

Lead (Pb) exposure poses devastating effects on central nervous system development of children. To replicate aspects of this neurotoxicity, we examined the effect of lead on the expression of apoptosis and of apoptosis-related genes, XIAP (X chromosome-linked inhibitor of apoptosis protein) and Smac (second mitochondrial activator of caspase), in the hippocampus of developing rats. A total of 48 rats (30-day old) were randomly divided into four groups for intragastrical perfusion of lead acetate [Pb(Ac)₂]: untreated, low (2 mg/kg/d), medium (20 mg/kg/d), and high (200 mg/kg/d) dose groups. Pb content was determined in blood, and the apoptosis indexes and XIAP and Smac gene expression were analyzed in the hippocampus. There was a significant difference in apoptosis indexes (AI) between the exposed and control groups (p < 0.01). AI was highest in the high exposure group. XIAP gene expression was reduced in the exposed groups and the expression was negatively correlated with blood lead levels (BLLs) (p < 0.05). But the four groups did not differ in the expression of Smac (p > 0.05). Our data indicate that exposure to Pb(Ac)₂ caused a dose-dependent and significant increase of apoptosis in the hippocampus of developing rats through depressing the expression of the XIAP but not the Smac genes.     

The Effects of FeCl<Subscript>3</Subscript> and Fe–EDTA on the Development of Psoriasis

The effects of FeCl₃ and Fe–EDTA on the development of psoriasis were studied in the mouse model of vaginal epithelium and tail epidermis. The mitoses of vaginal epithelial cell in female mice of their estrogenic stage and the formation of granular cell layers in male mouse tail scale were observed. Mice were randomly divided into eight groups and treated with normal saline, methotrexate, and different doses of two iron forms, FeCl₃ and Fe–EDTA, respectively, for 10 days. To explore the influence of FeCl₃ and Fe–EDTA on the excretion of Cu, Fe, Zn, Ca, Mg, Mn, and Se, the concentration of those elements in liver and kidney was analyzed by atomic absorption spectrometry. The different doses of FeCl₃ or Fe–EDTA could obviously inhibit the mitoses of vaginal epithelial cell (p< 0.05) and promote the formation of granular cell layers in mice tail scale (p < 0.05). No statistically significant results were found between the groups of FeCl₃ and Fe–EDTA, and between experimental groups and methotrexate group acted as the positive control (p>0.05). Compared with the negative group, the concentrations of Cu, Fe, Zn, Ca, Mg, Mn, and Se in liver and kidney of experimental groups and positive control group were not significantly changed (p > 0.05). FeCl₃ and Fe–EDTA are as effective as methotrexate on inhibiting hyperplasia of epidermal cells and increasing the formation of granular cell layers, and the concentrations of Cu, Fe, Zn, Ca, Mg, Mn, and Se in liver and kidney of experimental groups and positive control group were not significantly changed compared with the negative group, possibly retarding the development of psoriasis.