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Jesse P. Goff - One of the best experts on this subject based on the ideXlab platform.
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diet induced pseudohypoparathyroidism a hypocalcemia and Milk Fever risk factor
Journal of Dairy Science, 2014Co-Authors: Jesse P. Goff, Annette Liesegang, Ronald L HorstAbstract:Abstract Subclinical hypocalcemia may affect half of all multiparous cows, and clinical hypocalcemia or Milk Fever affects approximately 5% of dairy cows each year. This disorder of calcium homeostasis can be induced by several dietary factors. Recent studies implicate high dietary potassium and high dietary cation-anion difference (DCAD) with increased risk of Milk Fever. The hypothesis tested in this study was that high-DCAD diets fed to prepartum cows reduce tissue sensitivity to parathyroid hormone (PTH), inducing a pseudohypoparathyroid state that diminishes calcium homeostatic responses. Multiparous Jersey cows were fed low- or high-DCAD diets in late gestation, creating a compensated metabolic alkalosis in the high-DCAD cows and a compensated metabolic acidosis in the low-DCAD cows. They then received synthetic PTH injections at 3-h intervals for 48h. Parathyroid hormone is expected to cause an increase in plasma calcium by increasing renal production of 1,25-dihydroxyvitamin D and increasing bone calcium resorption. Plasma calcium concentration increased at a significantly lower rate in cows fed the high-DCAD diet. Cows fed the high-DCAD diet also produced significantly less 1,25-dihydroxyvitamin D in response to the PTH injections than cows fed the low-DCAD diet. Serum concentrations of the bone resorption marker carboxyterminal telopeptide of type I collagen were numerically lower in cows fed the high-DCAD diet but this difference was not statistically significant. These data provide direct evidence that high-DCAD diets reduce tissue sensitivity to PTH. The metabolic alkalosis associated with high-DCAD diets likely induces a state of pseudohypoparathyroidism in some dairy cows at the onset of lactation, resulting in hypocalcemia and Milk Fever.
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The monitoring, prevention, and treatment of Milk Fever and subclinical hypocalcemia in dairy cows
Veterinary Journal, 2008Co-Authors: Jesse P. GoffAbstract:The periparturient cow undergoes a transition from non-lactating to lactating at calving. The animal is tremendously challenged to maintain calcium homeostasis. Those that fail can develop Milk Fever, a clinical disorder that is life threatening to the cow and predisposes the animal to a variety of other disorders. Guidelines for monitoring the incidence of hypocalcemia and methods for treating Milk Fever are reviewed. The physiological factors that cause Milk Fever and strategies for prevention of Milk Fever are discussed, focusing on the effects diet cation-anion difference can have on tissue sensitivity to parathyroid hormone. Another major risk factor for Milk Fever is hypomagnesemia, which is observed when animals are fed inadequate amounts of magnesium, or some factor is present in the diet that prevents adequate absorption of magnesium. Moderate hypomagnesemia impairs the ability of the cow to maintain calcium homeostasis and hypocalcemia occurs.
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macromineral physiology and application to the feeding of the dairy cow for prevention of Milk Fever and other periparturient mineral disorders
Animal Feed Science and Technology, 2006Co-Authors: Jesse P. GoffAbstract:The periparturient cow undergoes a transition from non-lactating to lactating at calving. The animal is tremendously challenged to maintain calcium homeostasis. Those that fail can develop Milk Fever, a clinical disorder that is life threatening to the cow and predisposes the cow to a variety of other disorders. Less dramatic sub-clinical hypocalcemia can also reduce productivity of cattle by reducing feed intake in early lactation. The cause and prevention of Milk Fever will be discussed, focusing on the role of diet cation–anion difference and use of low calcium diets. The periparturient period also typically causes minor perturbations in blood potassium and phosphorus concentrations. Occasionally these disturbances are severe enough to be the cause of recumbency and the “downer cow” syndrome. Pathogenesis of these syndromes will be discussed. Low blood magnesium concentrations are observed when animals are fed inadequate amounts of magnesium or some factor is present in the diet, which prevents adequate absorption of magnesium. Severe hypomagnesemia can cause tetany and the downer cow syndrome, but more commonly moderate hypomagnesemia impairs the ability of the cow to maintain calcium homeostasis and hypocalcemia occurs secondary to the hypomagnesemia.
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relative acidifying activity of anionic salts commonly used to prevent Milk Fever
Journal of Dairy Science, 2004Co-Authors: Jesse P. Goff, R Ruiz, Ronald L HorstAbstract:Abstract High cation diets can cause Milk Fever in dairy cows as they induce a metabolic alkalosis reducing the ability of the cow to maintain calcium homeostasis at the onset of lactation. Adding anions to the diet can offset the effect of the high cation forages by inducing a mild metabolic acidosis, restoring the ability to maintain calcium homeostasis. The difference in mEq of dietary cations and anions (DCAD) is most often expressed as (Na + + K + )−(Cl − + S − − ). This equation implies that a mEq of chloride and a mEq of sulfate are equipotent in their ability to alter acid-base balance of the cow. Using blood and urine pH to monitor effects on acid-base balance, experiments were conducted to test the relative acidifying activity of various sulfate and chloride anion sources in nonpregnant, nonlactating Jersey cows. Across all experiments, chloride proved to have about 1.6 times the acidifying activity of sulfate. Calcium and magnesium, ignored by the common DCAD equation, had a small but significant alkalinizing effect when accompanying chloride or sulfate. The ranking of the anion sources tested at a dose of 2 Eq/d, from most to least potent urine acidifier, was hydrochloric acid, ammonium chloride, calcium chloride, calcium sulfate, magnesium sulfate, and sulfur. These data should allow more accurate prediction of the response of late gestation cows to dietary cation-anion manipulation.
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using solanum glaucophyllum as a source of 1 25 dihydroxyvitamin d to prevent hypocalcemia in dairy cows
Acta Veterinaria Scandinavica, 2003Co-Authors: Ronald L Horst, Jesse P. Goff, M. E. Dallorso, S Gill, E PawlakAbstract:Reducing cation-anion difference of diets (DCAD) fed just before parturition can prevent Milk Fever. However this dietary regimen does not entirely eliminate hypocalcemia. Milk Fever can also be prevented by exogenous administration of the calcium regulating hormone 1,25-dihydroxyvitamin D. Unfortunately 1,25-dihydroxyvitamin D treatment remains expensive and the pre-partal diets used in most trials would be classified today as high in cations. Solanum glaucophyllum (Sg) is a plant that contains high levels of a glycoside form of 1,25-dihydroxyvitamin D. S. Glaucophyllum is widely distributed in the province of Buenos Aires in Argentina and in Brazil and causes the development of a calcinotic disease in cattle called "Enteque Seco". In order to become active the glycoside must be cleaved to liberate the 1,25(OH) 2 D 3 . Rumen microbes are very efficient at this process. Could administration of Sg leaves to cows that were already being fed a low DCAD pre-partum diet further improve calcium status at calving? Nine multiparous Jersey cows were fed a low DCAD diet prior to calving. Urine pH of cows was maintained below 7.0 in all cows the week prior to parturition. Five cows were daily given 2 or 3 g Sg leaves in gelatin boluses beginning 6 days (on average) before calving and continuing for the first 14 days of lactation. None of the four cows fed the low DCAD diet only developed Milk Fever. Their blood calcium concentration was 7.6, 7.0 and 8.0 mg/dl the day of calving and d 1 and 2 after calving respectively. Cows receiving Sg in addition to low DCAD diet had significantly higher blood calcium concentration during the periparturient period with blood calcium concentrations of 7.8, 8.8 and 9.3 mg/dl the day of calving and d 1 and 2 after calving respectively. Defining subclinical hypocalcemia as blood calcium <7.5 mg/dl, control cows suffered an average of 3 days of subclinical hypocalcemia and the Sg treated cows suffered 0.8 d of subclinical hypocalcemia the first 2 wk of lactation. Thus, Sg treatment improved calcium status in animals that were also being fed a low DCAD diet. Unfortunately, all cows receiving Sg suffered 1-2 days of hypocalcemia (1 cow developed Milk Fever) between 6 and 8 days after Sg treatment was ended. Mean blood calcium on d 22 of lactation of Sg cows was 6.9 mg/dl compared with 9.2 mg/dl in untreated cows. It appears that Sg treatment supplanted the cow's own calcium homeostasis mechanisms so that abrupt withdrawal of treatment left the cows temporarily unable to control blood calcium concentration. Additional experiments were conducted using a phased withdraw approach. Three cows were treated with Sg from 5 days prepartum to 7 postpartum (2 g Sg/d) from day 8-14 postpartum (1 g Sg/d) and day 15-21 postpartum (0.5 g Sg/d). The phased withdrawal approach resulted in normal calcium concentration for up to 2 weeks following cessation of Sg. These data suggest that Sg can be used successfully in the prevention of hypocalcemia and that a phased withdrawal approach to removing the exogenous source of 1,25-(OH) 2 D 3 was successful in avoiding the hypocalcemic side effects associated with abrupt withdrawal. 242
Ronald L Horst - One of the best experts on this subject based on the ideXlab platform.
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diet induced pseudohypoparathyroidism a hypocalcemia and Milk Fever risk factor
Journal of Dairy Science, 2014Co-Authors: Jesse P. Goff, Annette Liesegang, Ronald L HorstAbstract:Abstract Subclinical hypocalcemia may affect half of all multiparous cows, and clinical hypocalcemia or Milk Fever affects approximately 5% of dairy cows each year. This disorder of calcium homeostasis can be induced by several dietary factors. Recent studies implicate high dietary potassium and high dietary cation-anion difference (DCAD) with increased risk of Milk Fever. The hypothesis tested in this study was that high-DCAD diets fed to prepartum cows reduce tissue sensitivity to parathyroid hormone (PTH), inducing a pseudohypoparathyroid state that diminishes calcium homeostatic responses. Multiparous Jersey cows were fed low- or high-DCAD diets in late gestation, creating a compensated metabolic alkalosis in the high-DCAD cows and a compensated metabolic acidosis in the low-DCAD cows. They then received synthetic PTH injections at 3-h intervals for 48h. Parathyroid hormone is expected to cause an increase in plasma calcium by increasing renal production of 1,25-dihydroxyvitamin D and increasing bone calcium resorption. Plasma calcium concentration increased at a significantly lower rate in cows fed the high-DCAD diet. Cows fed the high-DCAD diet also produced significantly less 1,25-dihydroxyvitamin D in response to the PTH injections than cows fed the low-DCAD diet. Serum concentrations of the bone resorption marker carboxyterminal telopeptide of type I collagen were numerically lower in cows fed the high-DCAD diet but this difference was not statistically significant. These data provide direct evidence that high-DCAD diets reduce tissue sensitivity to PTH. The metabolic alkalosis associated with high-DCAD diets likely induces a state of pseudohypoparathyroidism in some dairy cows at the onset of lactation, resulting in hypocalcemia and Milk Fever.
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relative acidifying activity of anionic salts commonly used to prevent Milk Fever
Journal of Dairy Science, 2004Co-Authors: Jesse P. Goff, R Ruiz, Ronald L HorstAbstract:Abstract High cation diets can cause Milk Fever in dairy cows as they induce a metabolic alkalosis reducing the ability of the cow to maintain calcium homeostasis at the onset of lactation. Adding anions to the diet can offset the effect of the high cation forages by inducing a mild metabolic acidosis, restoring the ability to maintain calcium homeostasis. The difference in mEq of dietary cations and anions (DCAD) is most often expressed as (Na + + K + )−(Cl − + S − − ). This equation implies that a mEq of chloride and a mEq of sulfate are equipotent in their ability to alter acid-base balance of the cow. Using blood and urine pH to monitor effects on acid-base balance, experiments were conducted to test the relative acidifying activity of various sulfate and chloride anion sources in nonpregnant, nonlactating Jersey cows. Across all experiments, chloride proved to have about 1.6 times the acidifying activity of sulfate. Calcium and magnesium, ignored by the common DCAD equation, had a small but significant alkalinizing effect when accompanying chloride or sulfate. The ranking of the anion sources tested at a dose of 2 Eq/d, from most to least potent urine acidifier, was hydrochloric acid, ammonium chloride, calcium chloride, calcium sulfate, magnesium sulfate, and sulfur. These data should allow more accurate prediction of the response of late gestation cows to dietary cation-anion manipulation.
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using solanum glaucophyllum as a source of 1 25 dihydroxyvitamin d to prevent hypocalcemia in dairy cows
Acta Veterinaria Scandinavica, 2003Co-Authors: Ronald L Horst, Jesse P. Goff, M. E. Dallorso, S Gill, E PawlakAbstract:Reducing cation-anion difference of diets (DCAD) fed just before parturition can prevent Milk Fever. However this dietary regimen does not entirely eliminate hypocalcemia. Milk Fever can also be prevented by exogenous administration of the calcium regulating hormone 1,25-dihydroxyvitamin D. Unfortunately 1,25-dihydroxyvitamin D treatment remains expensive and the pre-partal diets used in most trials would be classified today as high in cations. Solanum glaucophyllum (Sg) is a plant that contains high levels of a glycoside form of 1,25-dihydroxyvitamin D. S. Glaucophyllum is widely distributed in the province of Buenos Aires in Argentina and in Brazil and causes the development of a calcinotic disease in cattle called "Enteque Seco". In order to become active the glycoside must be cleaved to liberate the 1,25(OH) 2 D 3 . Rumen microbes are very efficient at this process. Could administration of Sg leaves to cows that were already being fed a low DCAD pre-partum diet further improve calcium status at calving? Nine multiparous Jersey cows were fed a low DCAD diet prior to calving. Urine pH of cows was maintained below 7.0 in all cows the week prior to parturition. Five cows were daily given 2 or 3 g Sg leaves in gelatin boluses beginning 6 days (on average) before calving and continuing for the first 14 days of lactation. None of the four cows fed the low DCAD diet only developed Milk Fever. Their blood calcium concentration was 7.6, 7.0 and 8.0 mg/dl the day of calving and d 1 and 2 after calving respectively. Cows receiving Sg in addition to low DCAD diet had significantly higher blood calcium concentration during the periparturient period with blood calcium concentrations of 7.8, 8.8 and 9.3 mg/dl the day of calving and d 1 and 2 after calving respectively. Defining subclinical hypocalcemia as blood calcium <7.5 mg/dl, control cows suffered an average of 3 days of subclinical hypocalcemia and the Sg treated cows suffered 0.8 d of subclinical hypocalcemia the first 2 wk of lactation. Thus, Sg treatment improved calcium status in animals that were also being fed a low DCAD diet. Unfortunately, all cows receiving Sg suffered 1-2 days of hypocalcemia (1 cow developed Milk Fever) between 6 and 8 days after Sg treatment was ended. Mean blood calcium on d 22 of lactation of Sg cows was 6.9 mg/dl compared with 9.2 mg/dl in untreated cows. It appears that Sg treatment supplanted the cow's own calcium homeostasis mechanisms so that abrupt withdrawal of treatment left the cows temporarily unable to control blood calcium concentration. Additional experiments were conducted using a phased withdraw approach. Three cows were treated with Sg from 5 days prepartum to 7 postpartum (2 g Sg/d) from day 8-14 postpartum (1 g Sg/d) and day 15-21 postpartum (0.5 g Sg/d). The phased withdrawal approach resulted in normal calcium concentration for up to 2 weeks following cessation of Sg. These data suggest that Sg can be used successfully in the prevention of hypocalcemia and that a phased withdrawal approach to removing the exogenous source of 1,25-(OH) 2 D 3 was successful in avoiding the hypocalcemic side effects associated with abrupt withdrawal. 242
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Presence of Acute Phase Response in Normal and Milk Fever Dairy Cows Around Parturition
Acta Veterinaria Scandinavica, 2003Co-Authors: Burim N. Ametaj, Jesse P. Goff, Ronald L Horst, Barry J. Bradford, Donald C. BeitzAbstract:Milk Fever is a metabolic disease of dairy cows occurring at the onset of lactation and characterized by a rapid decline in the concentrations of calcium in plasma. Significant advances have been made during the last decade in the understanding of the pathogenesis of Milk Fever. The etiology of the disease, however, still remains unclear. The goal of the present study was to search for the presence of an acute phase response (APR) during the peripartal period in normal and Milk Fever dairy cows and the role that APR might play in the etiology of Milk Fever. Eight clinically healthy, pregnant Holstein dairy cows were selected. Approximately 3 wk before the expected date of calving as well as 2 wk after calving, animals were brought into individual tie stalls to be fed a diet with a cation-anion difference of +40 meq/100g. Three cows showed clinical signs of Milk Fever and were treated intravenously with a solution containing calcium borogluconate and magnesium gluconate, whereas the rest of the cows showed no clinical signs of postparturient diseases. Blood samples were obtained from jugular vein at 10, 5, and 1 d before parturition, on the day of parturition, as well as at 1, 5, and 10 d after parturition. Plasma samples were analyzed for serum amyloid A (SAA), calcitonin generelated peptide (CGRP), tumor necrosis factor-alpha (TNF-α), lactate, iron, and total calcium. Results show that concentrations of SAA in plasma from all cows increased from 706 µg/dL at 10 d before calving to 3096 µg/dL 1 d after calving and then declined to prepartal values. Concentrations of lactate in plasma also increased from 0.5 mmol/L at 10 d before parturition to 1.3 mmol/L on the day of parturition and then dropped to precalving values. Concentrations of iron and total calcium in plasma declined in both control and Milk Fever cows from 57 µg/dL and 8.7 mg/dL at 10 d before calving to 41 µg/dL and 6.4 mg/dL, respectively, on the day of parturition and then increased to precalving concentrations. Analysis showed detectable amounts of TNF-α in plasma of only one clinically normal cow. Concentrations of CGRP in plasma were high in both Milk Fever and normal cows before parturition at 59 pg/mL and then declined after calving at 27 pg/mL. Concentrations of SAA and iron in plasma were greater in Milk Fever cows compared with clinically normal ones at the day of parturition. Overall, data from the present study indicate the presence of an APR in both normal and Milk Fever cows. Calcitonin gene-related peptide, a 37-amino acid peptide generated by alternative tissue-specific splicing of the transcript of the calcitonin gene and a well-known inhibitor of calcium mobilization from bone in rodents, might play a significant role in regulation of calcium homeostasis as well as in the etiology and pathogenesis of Milk Fever in dairy cows. Further investigation is warranted to better understand the role of APR in the etiology and pathogenesis of Milk Fever of dairy cows.
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Milk Fever control in the United States.
Acta veterinaria Scandinavica. Supplementum, 2003Co-Authors: Jesse P. Goff, Ronald L HorstAbstract:Strategies for the prevention of Milk Fever in the United States have made several 180 degree changes over the last several decades. During the 1950's and 1960's evidence suggested that low calcium diets could be utilizedto stimulate the parathyroid prior to calving to initiate calcium homeostasis prior to the onset of lactation. High calcium diets were avoided and the strategy worked - for a while, until more concentrated farming practices changed the cation composition of the forages. Although Norwegian scientists presented evidence of a role for cations and anions in Milk Fever during the late 1960's, recent studies have more precisely defined the physiological link between high diet potassium and tissue sensitivity to parathyroid hormone as a leading cause of Milk Fever. Manipulation of dietary cation-anion balance has been growing rapidly as a means of controlling not only Milk Fever but sub-clinical hypocalcemia as well. A recent United States survey found that 45% of dairy operations feed dry cows a "low potassium diet" to reduce Milk Fever. In addition some use anionic salts. About 27% of dairy farms feed dry cows a diet with added anions to induce a compensated metabolic acidosis which has proved effective in reducing sub-clinical hypocalcemia. These diets are often high in calcium.
J Wedam - One of the best experts on this subject based on the ideXlab platform.
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field trials of an oral calcium propionate paste as an aid to prevent Milk Fever in periparturient dairy cows
Journal of Dairy Science, 1996Co-Authors: Jesse P. Goff, P W Jardon, Ronald L Horst, Claudia Borelli, J WedamAbstract:Abstract Trials were conducted to test the efficacy of a calcium propionate paste as an aid to prevent Milk Fever and to improve the health of dairy cows. Each calcium propionate treatment tube supplied 37g of calcium. In trials involving Holstein herds and a Jersey herd, two (trials 1 and 2) or three (trial 3) calcium propionate tubes were given at calving and again at 12h after calving. For the Jersey herd, calcium propionate treatment (two tubes) reduced the incidence of Milk Fever from 50% in control cows to 29% in treated cows. Plasma obtained 24h after calving from treated cows had higher calcium, lower NEFA, and lower β -hydroxybutyrate concentrations than did plasma from control cows. No other benefits of calcium propionate treatment were significant for health or for productivity of the cows. Calcium propionate treatment had no significant effects on blood calcium, NEFA, or s-hydroxybutyrate in the Holstein herds studied. However, calcium propionate did reduce the number of cows with subclinical hypocalcemia (≤7.5 mg/dl of plasma calcium) at 24h after calving in both trials involving Holstein cows. Calcium Propionate treatment was beneficial in reducing subclinical hypocalcemia in all trials and reduced the incidence of Milk Fever in a herd having a problem with Milk Fever.
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Field trials of an oral calcium propionate paste as an aid to prevent Milk Fever in periparturient dairy cows.
Journal of dairy science, 1996Co-Authors: Jesse P. Goff, P W Jardon, Ronald L Horst, Claudia Borelli, J WedamAbstract:Trials were conducted to test the efficacy of a calcium propionate paste as an aid to prevent Milk Fever and to improve the health of dairy cows. Each calcium propionate treatment tube supplied 37 g of calcium. In trials involving Holstein herds and a Jersey herd, two (trials 1 and 2) or three (trial 3) calcium propionate tubes were given at calving and again at 12 h after calving. For the Jersey herd, calcium propionate treatment (two tubes) reduced the incidence of Milk Fever from 50% in control cows to 29% in treated cows. Plasma obtained 24 h after calving from treated cows had higher calcium, lower NEFA, and lower beta-hydroxybutyrate concentrations than did plasma from control cows. No other benefits of calcium propionate treatment were significant for health or for productivity of the cows. Calcium propionate treatment had no significant effects on blood calcium, NEFA, or beta-hydroxybutyrate in the Holstein herds studied. However, calcium propionate did reduce the number of cows with subclinical hypocalcemia (< or = 7.5 mg/dl of plasma calcium) at 24 h after calving in both trials involving Holstein cows. Calcium propionate treatment was beneficial in reducing subclinical hypocalcemia in all trials and reduced the incidence of Milk Fever in a herd having a problem with Milk Fever.
R. J. Jørgensen - One of the best experts on this subject based on the ideXlab platform.
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Preventive strategies and risk factors for Milk Fever in Danish dairy herds: a questionnaire survey.
Preventive veterinary medicine, 2007Co-Authors: S.s. Hansen, J.y. Blom, Annette Kjær Ersbøll, R. J. JørgensenAbstract:Abstract Milk Fever is a commonly recognized production disease in dairy cows around parturition. The aim of this questionnaire survey was therefore to investigate Milk Fever preventive strategies used in Danish dairy herds during 1998, to explore the reasons for choosing a specific strategy, and finally to evaluate possible risk factors for Milk Fever occurrences. A random sample of 230 Milk producers (MP) was drawn from the Danish Cattle Database. A telephone interview (TI) was used to collect data. A sub-sample of 25% MPs was chosen by systematic random sampling and interviewed a second time (TI 2 ). Descriptive analysis of all answers was performed. The agreement between TI 1 and TI 2 was evaluated using Cohen's kappa coefficient and the overall intra-MP agreement. Risk factors (such as housing systems or use of Milk Fever preventive strategies) for differences in Milk Fever incidences between herds were evaluated using logistic regression. This investigation revealed that Danish MPs focused on a few well-described Milk Fever preventive principles and other management methods, such as reduced Milking and management of body condition. There was no significant difference in risk of developing Milk Fever using different prevention strategies ( p = 0.80). Furthermore, the logistic regression did not indicate an association between reported Milk Fever cases and the assessments of this as a problem or not ( p = 0.09). Tie stalls increased the risk of Milk Fever compared to loose housing systems ( p = 0.019). There was a significant difference in risk of Milk Fever between parities. The overall Milk Fever incidence risk was 3.0%.
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Milk Fever Control Principles: A Review
Acta veterinaria Scandinavica, 2002Co-Authors: T Thilsing-hansen, R. J. Jørgensen, Søren Dinesen ØstergaardAbstract:Three main preventive principles against Milk Fever were evaluated in this literature review, and the efficacy of each principle was estimated from the results of controlled investigations. Oral calcium drenching around calving apparently has a mean efficacy of 50%–60% in terms of Milk Fever prevention as well as prevention of Milk Fever relapse after intravenous treatment with calcium solutions. However, some drenches have been shown to cause lesions in the forestomacs. When using the DCAD (dietary cation-anion difference) principle, feeding rations with a negative DCAD (measured as (Na + K) – (Cl + S)) significantly reduce the Milk Fever incidence. Calculating the relative risk (RR) of developing Milk Fever from controlled experiments results in a mean RR between 0.19 and 0.35 when rations with a negative versus positive DCAD are compared. The main drawback from the DCAD principle is a palatability problem. The principle of feeding rations low in calcium is highly efficient in Milk Fever prevention provided the calcium intake in the dry period is kept below 20 g per day. Calculating the relative risk (RR) of developing Milk Fever from controlled experiments results in a very low mean RR (between 0 and 0.20) (daily calcium intake below versus above 20 g/d). The main problem in implementing the low-Ca principle is difficulties in formulating rations sufficiently low in calcium when using commonly available feeds. The use of large doses of vitamin D metabolites and analogues for Milk Fever prevention is controversial. Due to toxicity problems and an almost total lack of recent studies on the subject this principle is not described in detail. A few management related issues were discussed briefly, and the following conclusions were made: It is important to supply the periparturient cow with sufficient magnesium to fulfil its needs, and to prevent the dry cows from being too fat. Available information on the influence of carbohydrate intake, and on the effect of the length of the dry period and prepartum Milking, is at present insufficient to include these factors in control programmes.
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hot topic prevention of parturient paresis and subclinical hypocalcemia in dairy cows by zeolite a administration in the dry period
Journal of Dairy Science, 2001Co-Authors: T Thilsinghansen, R. J. JørgensenAbstract:To test the effects of a zeolite feed supplement on parturient calcium status and Milk Fever, two groups of dry cows were treated with either 1 kg of zeolite/d or none for 4 wk prepartum. At calving and d 1 and 2 after calving all cows were given 250 g of calcium carbonate as a drench, and a blood sample was taken. Serum calcium analysis revealed a greater calcium concentration in zeolite-treated cows. While three control cows contracted Milk Fever, necessitating intravenous calcium therapy, and six out of eight control cows experienced serum calcium levels below 2 mmol/L in one or more samples taken, none of the zeolite-treated cows contracted Milk Fever or experienced subclinical hypocalcemia.
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Milk Fever and subclinical hypocalcaemia--an evaluation of parameters on incidence risk, diagnosis, risk factors and biological effects as input for a decision support system for disease control
Acta veterinaria Scandinavica, 2001Co-Authors: Hans Houe, T Thilsing-hansen, R. J. Jørgensen, Søren Dinesen Østergaard, Jan Tind Sørensen, Torben Larsen, Jens Frederik Agger, J.y. BlomAbstract:The present review analyses the documentation on incidence, diagnosis, risk factors and effects of Milk Fever and subclinical hypocalcaemia. It is hereby evaluated whether the existing documentation seems sufficient for further modelling in a decision support system for selection of a control strategy. Several studies have been carried out revealing an incidence of Milk Fever most often in the level of 5-10%. Few studies indicate that the incidence of subclinical hypocalcaemia is several times higher than Milk Fever. The diagnosis based on clinical or laboratory methods or based on presence of risk factors is outlined. The clinical symptoms of Milk Fever are highly specific and the disease level may thus be determined from recording of treatments. Diagnosis of subclinical hypocalcaemia needs to include laboratory examinations or it may be determined by multiplying the incidence of Milk Fever by a certain factor. From the documentation on risk factors, it is very complex to predict the incidence from the exposure level of the risk factors. Due to uncertainty, sensitivity analyses over a wide range of values for each parameter are needed. The documentation of cow characteristics, nutrition, environment and management as risk factors are described. Among cow characteristics, parity or age, body condition and production level were found to be important. Risk factors associated with nutrition included most importantly dietary cation-anion difference and calcium level whereas the importance of general feeding related factors like type of feed stuff and feeding level were less clear. Environment and management included season, climate, housing, pasturing, exercise, length of dry period and prepartum Milking. Several of the parameters on environment and management were confounded among each other and therefore firm conclusions on the importance were difficult. The documentation of the effect of Milk Fever includes the downer cows, reproductive disorders, occurrence of other diseases and the effect on Milk production, body weight and culling. The reproductive disorders included most importantly dystocia, uterine prolapse, retained placenta, metritis and repeat breeding, and occurrence of other diseases included ketosis, displaced abomasum and mastitis. The documentation was substantial and often quantifiable within certain limits. Overall it is concluded that the present documentation on Milk Fever concerning incidence, diagnosis, risk factors and effects seems sufficient for a systematic inclusion in a decision support system. A model on Milk Fever should take into consideration the variation in biological data and individual herd characteristics. The inclusion of subclinical hypocalcaemia would be more uncertain and probably should await further documentation on possibilities of determining the herd level incidence and also the effect of this condition on production.
Jan Tind Sørensen - One of the best experts on this subject based on the ideXlab platform.
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A stochastic model simulating Milk Fever in a dairy herd
Preventive Veterinary Medicine, 2003Co-Authors: Søren Dinesen Østergaard, Jan Tind Sørensen, Hans HoueAbstract:A simulation model was developed to evaluate the long-term effect of control strategies against Milk Fever (MF); here, we present the base model and sensitivity analyses. The representation of the within-herd dynamics was based on the existing SimHerd II model. Because of the relationships between MF and other diseases, the new model (called "SimHerd III") includes diseases common in a dairy herd. The cow level risk factors modelled were: base risk in the herd, parity, Milk-yield potential, lactational disease recurrence, disease interrelationships, body condition and season. The diseases include clinical cases of MF, dystocia, downer-cow syndrome, retained placenta, metritis, displaced abomasum, ketosis and mastitis. The effects of diseases were represented by daily Milk yield, daily body weight, daily feed intake, risk of stillbirth, conception probability, decision on culling, death and immediate removal. Simulated technical results showed that the herd effects of reduced risk of MF differed according to the reproductive efficiency in the herd. These interactions between reproduction efficiency and the effect of reduced base risk of MF were related to differences in how the simulated herds reacted to the reduction in replacements caused by MF. In the sensitivity analysis, eight potential key parameters were changed to their lowest and highest expected values retrieved from the literature. When measuring the sensitivity on Milk production in the herd (as the economically most important technical effect), the model seemed most sensitive to the uncertainty of effect of MF on death risk and MF-recurrence risk.
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Expert opinions of strategies for Milk Fever control.
Preventive veterinary medicine, 2002Co-Authors: Jan Tind Sørensen, Søren Dinesen Østergaard, Hans Houe, Jens HindhedeAbstract:Dairy cows have several risk factors for Milk Fever. The most-suitable strategy to control Milk Fever in a specific herd will depend on herd-specific circumstances such as the attitude and skills of the farmer, the opportunities available in the production system and the economic consequences of a certain strategy. To develop feasible strategies in a modern loose-housing dairy herd, we carried out an expert opinion study. Animal husbandry advisors and veterinary practitioners were used as experts. The experts quantified the effect on Milk Fever and time needed by the farmer for two preselected options: Ca-gel fed orally peripartum and a low dietary cation-anion-difference in the dry-cow ration. The estimated mean relative risk (compared to no strategy) was 0.45 and 0.42, respectively, and the median time needed by the farmer was 7 and 33 min, respectively, per cow year. The experts also suggested 12 control strategies. The two control strategies, which were predicted to be the most, relevant were Ca-gel fed orally peripartum used alone and used in combination with a low Ca dry-cow diet.
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Milk Fever and subclinical hypocalcaemia--an evaluation of parameters on incidence risk, diagnosis, risk factors and biological effects as input for a decision support system for disease control
Acta veterinaria Scandinavica, 2001Co-Authors: Hans Houe, T Thilsing-hansen, R. J. Jørgensen, Søren Dinesen Østergaard, Jan Tind Sørensen, Torben Larsen, Jens Frederik Agger, J.y. BlomAbstract:The present review analyses the documentation on incidence, diagnosis, risk factors and effects of Milk Fever and subclinical hypocalcaemia. It is hereby evaluated whether the existing documentation seems sufficient for further modelling in a decision support system for selection of a control strategy. Several studies have been carried out revealing an incidence of Milk Fever most often in the level of 5-10%. Few studies indicate that the incidence of subclinical hypocalcaemia is several times higher than Milk Fever. The diagnosis based on clinical or laboratory methods or based on presence of risk factors is outlined. The clinical symptoms of Milk Fever are highly specific and the disease level may thus be determined from recording of treatments. Diagnosis of subclinical hypocalcaemia needs to include laboratory examinations or it may be determined by multiplying the incidence of Milk Fever by a certain factor. From the documentation on risk factors, it is very complex to predict the incidence from the exposure level of the risk factors. Due to uncertainty, sensitivity analyses over a wide range of values for each parameter are needed. The documentation of cow characteristics, nutrition, environment and management as risk factors are described. Among cow characteristics, parity or age, body condition and production level were found to be important. Risk factors associated with nutrition included most importantly dietary cation-anion difference and calcium level whereas the importance of general feeding related factors like type of feed stuff and feeding level were less clear. Environment and management included season, climate, housing, pasturing, exercise, length of dry period and prepartum Milking. Several of the parameters on environment and management were confounded among each other and therefore firm conclusions on the importance were difficult. The documentation of the effect of Milk Fever includes the downer cows, reproductive disorders, occurrence of other diseases and the effect on Milk production, body weight and culling. The reproductive disorders included most importantly dystocia, uterine prolapse, retained placenta, metritis and repeat breeding, and occurrence of other diseases included ketosis, displaced abomasum and mastitis. The documentation was substantial and often quantifiable within certain limits. Overall it is concluded that the present documentation on Milk Fever concerning incidence, diagnosis, risk factors and effects seems sufficient for a systematic inclusion in a decision support system. A model on Milk Fever should take into consideration the variation in biological data and individual herd characteristics. The inclusion of subclinical hypocalcaemia would be more uncertain and probably should await further documentation on possibilities of determining the herd level incidence and also the effect of this condition on production.
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a stochastic model simulating the feeding health production complex in a dairy herd
Journal of Dairy Science, 2000Co-Authors: Soren Ostergaard, Jan Tind Sørensen, Anders Ringgaard KristensenAbstract:A dynamic, stochastic, and mechanistic Monte Carlo model, simulating a dairy herd with focus on the feeding-health-production complex is presented. By specifying biological parameters at cow level and a management strategy at herd level, the model can simulate the technical and economic consequences of scenarios at herd level. The representation of the feeding-health-production complex is aimed to be sufficiently detailed, to include relationships likely to cause significant herd effects, and to be sufficiently simple to enable a feasible parameterization of the model and interpretation of the results from the model. Consequently, diseases are defined as four disease types: two metabolic disease types, an udder disease type, and a reproductive disease type. Risk factors for the diseases were defined as parity, yield capacity, disease recurrence, disease interrelationships, lactation stage, and season. Direct effects of the diseases were defined according to Milk yield, feed intake, feed utilization, conception, culling, involuntary removal, and death. Scenarios differing in base risks of Milk Fever and ketosis, heat detection rate, and culling strategy were simulated for describing the model behavior. Annual Milk yield per cow was decreased by increased risk of ketosis and by increased risk of Milk Fever, even though no direct effect of Milk Fever on Milk yield was modeled at the cow level. The indirect effect from Milk Fever is a consequence of increased replacement rate (relatively lower Milk yield from younger cows). By ignoring the history of Milk Fever in insemination and replacement decisions, a significantly reduced net income per cow was found in some herds. We concluded that important benefits from using such a herd model are the capability of accounting for herd management factors and the advantage of avoiding to double count the indirect effects from disease, such as increased risk of other diseases, poorer reproduction results, and increased risk of culling and death.