Sel-Plex in Beef Diets. Dr. Sim o n J. Tim m e rm a ns

Transcription

1 Sel-Plex in Beef Diets Dr. Sim o n J. Tim m e rm a ns

2 Why do beef cattle have trouble maintaining optimum Se status? Feed ingredients and forages vary in naturallyoccurring Se Rumen bugs reduce selenite, leaving less than 25% available to animal Inorganic Se can not be stored, leaving animal with tissue reserves Classic Se-related deficiencies persist despite supplementation with 0.3 ppm inorganic Se

3 Symptoms of Selenium Deficiency in Cattle Animal Newborn and Young Calves Growing Calves Symptoms WMD Unthriftiness Weak Calf Syndrome Unthrifitness Sub-Optimal Performance Increased Susceptibilty to BRD Low Growth Rates Poor Survival Weight loss and diarrhea Decreased immune response Cows Retained Placenta Metritis and Cystic Ovaries Still born calves Infertility Bulls Early Embryonic Deaths Low Sperm Motility

4 Sel-Plex Benefits for Beef Immune function Reproductive health Reduced retained placentas Fertility and sperm quality Calf health and vitality Improved meat quality Less drip loss Nutritional value of meat

5 3 Problem Areas on Beef Operations 1. Reproduction 2. Immunity 3. Viability in early postnatal life

6 Se Relationship to Male Fertility is Well Understood Both Antioxidant and Structural Roles Selenium is preferentially retained in testes Antioxidant role of PH-GSH-Px during sperm maturation Structural role of insoluble PH- GSH-Px in sperm mid-piece Selenium plays a role in sperm caps enzyme capability Normal Se deficient

7 Replacement Heifer and Cow Fertility Sel-Plex increased reproductive performance Decreased days to first breeding Decreased calving interval Less services per conception Reduced incidences of RP (Groenewegen et al., 2007) (Qiang et al., 2007)

8 Selenium and the Pre-Parturient Cow At calving tissue reserves at lowest Se deficiency in dam can lead to poor/weak calves, depressed immune system, and thyroid problems Calf Se status depends on dam: little inorganic crosses placenta only organic form of Se (such as Sel-Plex) can be effectively transferred from cow to calf via colostrum and milk

9 Sel-Plex on Fresh Cow Problems Inorganic Se Sel-Plex Incidence (%) RP (%) Metritis (%) Fever (%) Mastitis (%) Ketosis (%) Endometritis(%) Source effects: P>0.10 for all measures Cerri et al J. Dairy Sci. 89(Suppl. 1):53 (Abstr.)

10 Serum IgM Content of Cows at Parturition ppm (Selenite) 60 ppm (Selenite) 120 ppm (Selenite) 60 ppm (Sel-Plex) Cow serum Awadeh et al,1998 JAS

11 Maternal Se Status at Calving: Inorganic NaSe vs. Sel-Plex U/ml Selenite, 6 mg/d Sel-Plex, 6 mg/d Se, ug/l Selenite, 6 mg/d Sel-Plex, 6 mg/d Higher GSH-Px activity Higher whole blood Se Hemken et al., 1998

12 Plasma Selenium Concentration of Dams Plasma Se ( μg/l) Start Calving ab Means differ P < 0.05 Sel-Plex 0.5 ppm Na-Se 0.5 ppm Na-Se 0.1 ppm Guyot et al., 2006

13 Se Concentration in Colostrum and Milk Se ( μg/l) Birth D 75 Sel-Plex 0.5 ppm Na-Se 0.5 ppm Na-Se 0.1 ppm ab Means differ P < 0.05 Goyot et al., 2006c

14 Neonatal Diarrhea Incidence in Calves Odds ratio: 10.2 for Sel-Plex 0.5 versus Na-Se 0.1. Probability of diarrhea almost 10-fold higher in Na-Se 0.1 group vs. Sel-Plex Frequency % Sel-Plex 0.5 Na-Se 0.5 Na-Se 0.1 ab Means differ P < 0.05 Gyot et al., 2006

15 Average Daily Gain of Calves a 600 Frequency % b 510 b Sel-Plex 0.5 Na-Se 0.5 Na-Se 0.1 ab Means differ P < 0.05 Gyot et al., 2006

16 Calf Liver Se at Birth Tissue Se, ug/kg Control Deposel Mu-Se Sodium Selenite Sel-Plex 250 Bars with different letters differ (P < 0.05) Davis et al., 2005

17 Calf Whole Blood Se Over Time Blood Se, ug/l Control Deposel Mu-Se Sodium Selenite Sel-Plex Calf Age, d Davis et al., 2005

18 Weaning Weight, 205 d Control BWT, lbs Deposel Mu-Se Sodium Selenite Sel-Plex Davis et al., 2005

19 Se/Thyroid Responses and Cold Se-deficient calves born in cold weather are more sensitive to cold. Resistance Non-shivering thermogenesis in brown adipose tissue keeps neonates warm in early life Thyroid hormone (T3) stimulates heat production

20 Stress Increases Incidence of Disease When a cow is stressed, his body activates a stress adaptation response. This response causes an increased level of cortisone in the blood, which results in an inhibition of the cow s immune response which makes him more susceptible to infection.

21 Blood Se and GSH-Px Increase No Se Selenite Sel-Plex No Se vs. Se Na Se vs. SP Whole Blood Se, ng/ml (cows) P Value Early December Early February April Whole blood Se, ng.ml (calves) Birth Late May

22 Sel-Plex Can Improve Immune Function in Calves Item No Se Na Se Sel-Plex SE Whole blood Se, ng/ml 54.7 a b c 8.4 GSH-Px, EU/g Hb a b b 19.4 Macrophage phagocytosis, % 5.0 a 4.2 a 9.2 b EU/g Hb = nanomoles of NADPH oxidized min/gm of hemoglobin. 2 % of macrophages that phagocytized at least one porcine RBC. abc LS means within rows with differing superscripts differ (P<0.01).

23 Sel-Plex Improves Active Immune Response in Calves Macrophage Phagocytosis, % No Se Selenite Sel-Plex Gunter et al., University of Arkansas

24 Problems with Receiving Calves Stress associated with weaning, transportation Exposure to several challenges due to co-mingling Low feed intake during stress Most common disease: BRD

25 The Importance of Passive Immune Transfer Antibody concentrat Passive immunity (colostrum) High risk period Active immunity (immune system) 1 d 14 d Time

26 When and Why Do Calves Die? 70 61% scours Scours Resp Joint Other Unk. 62% of all deaths by 21 days of age. Cause 25% pneumonia 14% other/ unknown 27% within first week of life 21% within second week 14% third week Thomas, 2006

27 Neonatal Diarrhea Incidence in Calves Odds ratio: 10.2 for Sel-Plex 0.5 versus Na-Se 0.1. Probability of diarrhea almost 10-fold higher in Na-Se 0.1 group vs. Sel-Plex Frequency % b 35 b a Sel-Plex 0.5 Na-Se 0.5 Na-Se 0.1 ab Means differ P < 0.05 Gyot et al., 2006

28 Average Daily Gain of Steers Days 0 28, Receiving Period lbs/day No Se, E Sel-Plex E Sel-Plex E Sel-Plex E Selenite E Selenite E Sel-Plex vs. Selenite, P < 0.09 Sel-Plex 125 E vs. Selenite 500 E, P < 0.05 Sel-Plex 250 E vs. Selenite 500 E, P < 0.01

29 Summary Current recommendations may be too low for optimum health, reproductive function and immunity Mineral deficiencies can be due to interferences (high iron, sulfur) as well as low levels in feeds and forages It is more economical to maintain adequate mineral status than to try to catch up Residual effects of a sound mineral program adds value to your calf crop

30 Move beyond basic to optimum performance Better Immunity Improved Fertility Increased Viability

31 The effect of dietary supplementation of selenium on the immune functions of bovine polymorphornuclear leukocytes Aloysius Ibeagha, Jalil Mehrzad, Eveline Ibeagha-Awemu and Xin Zhao Department of Animal Science, McGill University, Quebec, Canada

32 Introduction to Selenium and immune function The question and objective Experiment design and Results Take-home message

33 Selenium Exists in several inorganic states: Se 2 Se 4+ Se 6+ (selenide, Selenite and Selenate) Is a micro or trace Mineral: provided to the animal as: ppm = mg/kg Is similar to and replace sulfur in amino acids: selenomethionine, selenocysteine and selenocystine

34 Selenocysteine Selenium is incorporated as selenocysteine into a wide range of selenoproteins. At least 50 have been identified. Not so many have been identified in bovine. This amino acid is specifically coded for in the mrna of selenoproteins. Selenocysteine UGA Stop codon UGA

35 Their metabolisms are also different. Selenium Supplementation Two forms of Se: Se (Selenite and Selenate) and organic Se inorganic The organic Se shows higher capacity of assimilation and bioavailability when compared to the inorganic form (Weiss and Hogan, 2005; Juniper et al., 2006).

36 Selenium dependent enzymes Glutathione peroxidase GSH + H 2 O 2 GSSG + H 2 O Iodothyronine deiodinases Thioredoxin Reductase Selenophosphate Synthetase Selenoprotein P Selenoprotein W, etc

37 Physiological functions of Selenium acts as an antioxidant is involved in thyroid hormone metabolism participates in redox reactions improves immune functions - Improves killing ability of neutrophils - Reduces the prevalence and severity of mastitis

38 Selenium Supplementation The level of Se supplementation varies from country to country and is determined largely by the Se status in feedstuff as influenced by soil Se status. Both sources of Se can be supplemented at 0.3 mg Se/ Kg of DM in Canada and the United States and 0.5 mg Se/Kg of DM in the EU.

39 Neutrophils form the first line of immune defense against invading pathogens in mammary glands Dosogne et al., During intramammary infection, Neutrophils form > 95% milk somatic cells

40 Function of neutrophils: Phagocytosis nucleus enzyme sac bacteria vacuoles pseudopodia

41 Neutrophil Bactericidal Functions Bacterial Killing Oxygen-dependent Superoxide anion Hydrogen peroxide Hydroxyl radial Oxygen-independent (Degranulation) Release of granule contents phagosomes Extracellular environment (Trowbridge & Emling, 1997)

42 Introduction to Selenium and immune function The question and objective Experiment design and Results Take-home message

43 Observation Sel-Plex reduced somatic cell counts in milk (Harrison et al., 2005) Question How does Sel-Plex affect neutrophil functions? Objectives To compare the effect of supplemented inorganic and organic selenium on neutrophil functions in high producing dairy cows during the periparturient period.

44 Introduction to Selenium and immune function The question and objective Experiment design and Results Take-home message

45 xperimental Design roup 1 : Control with no Se supplementation roup 2 : Low level of organic Se (0.3 mg/dm) roup 3 : High level of organic Se (0.5 mg/kg DM) elplex 2000 (Alltech Inc.) roup 4 : Low level of inorganic Se (0.3 mg/kg DM) roup 5 : High level of inorganic Se (0.5 mg/kg DM). odium selenite as the inorganic form. he experiment started 4 wks before parturition and finished 4 wks after parturition his is an on-going trial, the final results are expected in July, 2007.

46 Parameters to be measured Milk somatic cell counts (SCC) Oxidative burst Apoptosis and necrosis Phagocytosis Total protein content of milk Total fat content of milk Total milk production Plasma (cows and calves) Se concentration Milk (and colostrum) Se concentration Se content in DM (feed)

47 Organic Se reduces somatic cell counts (SCC)

48 Phagocytosi s Phagocytosis was performed using a Phagotest kit. It uses an opsonized FITC-labeled E. coli bacteria which is applied to heparinized whole blood samples to determine phagocytosis.

49 Phagocytosis in control samples (top) and treated samples (bottom)

50 There is no difference among groups for phagocytosis Phagocytosis (%) Inorganic Se Organic Se Se supplementation (mg/kg DM) Control

51 DHR 123 determines the percentage of phagocytic cells which produce reactive oxidants (conversion of DHR 123 to Rhodamine 123) and their enzymatic activity. Oxidative burst Oxidative burst was performed using a Bursttest (Phagoburst) kit. Escherichia coli bacteria was used to activate heparinized whole blood for 10 min at 38.5 ºC followed by incubation with a fluorogenic substrate dihydrorhodamine (DHR) 123 at 38.5 ºC for another 10 min.

52 Organic Se increases oxidative burst

53 Apoptosis and necrosis Apoptosis and necrosis assays were done by dualcolour FCM procedure using FITC-labeled Annexin V and PI. Q1 Q3 Q2 Q4 Hypothetical apoptotic and necrotic assay for dual Annexin Vand PI flourochromes showing various quadrants.

54 Organic Se reduces neutrophil apoptosis

55 Organic Se increases live cell % in comparison with inorganic Se Inorganic Inorganic Organic Organic Control 94

56 Introduction to Selenium and immune function The question and objective Experiment design and Results Take-home message

57 Take-home message Organic Se performed better than inorganic Se based on its oxidative capacity, apoptosis and cell survival ability. These will lead to more efficient killing of bacteria by neutrophils. The precise role of Se in modulating bovine cellular immunity appears to be complex. Only when all the selenoproteins have been identified and characterized can we fully understand the role of Se in host resistance. We recommend that Se be supplemented at a level of 0.5 mg/kg DM to boost the cow s immune system. Furthermore, organic Se should be used.

58 We thank Alltech Inc. for sponsoring this project.