Prevention of parturient paresis (milk fever) in dairy cows

Parturient paresis (milk fever) is a hypocalcemic disorder of dairy cows associated with the onset of lactation. In these studies, we have evaluated the ability of two calcitropic hormones, 1,25-dihydroxyvitamin D and parathyroid hormone, to prevent parturient paresis;Studies utilizing 1,25-dihydroxyvitamin D and its fluorinated analogues established that these compounds will prevent hypocalcemia if administered at the proper time prior to parturition. These studies confirm earlier work that the vitamin D compounds are effective solely by virtue of their ability to increase intestinal absorption of calcium. The studies also warn of possible renal toxicity that may accompany use of these compounds at high doses;Parathyroid hormone was found to increase plasma calcium concentration in periparturient cows through its activity on bone calcium resorption mechanisms, renal calcium conservation, and intestinal calcium absorption via its stimulation of the production of 1,25-dihydroxyvitamin D. These studies establish that parathyroid hormone can prevent parturient paresis in dairy cattle

Innate immune response to intramammary infection with Serratia marcescens and Streptococcus uberis

Streptococcus uberis and Serratia marcescens are Gram-positive and Gram-negative bacteria, respectively, that induce clinical mastitis. Once initial host barrier systems have been breached by these pathogens, the innate immune system provides the next level of defense against these infectious agents. The innate immune response is characterized by the induction of pro-inflammatory cytokines, as well as increases in other accessory proteins that facilitate host recognition and elimination of the pathogens. The objective of the current study was to characterize the innate immune response during clinical mastitis elicited by these two important, yet less well-studied, Gram-positive and Gram-negative organisms. The pro-inflammatory cytokine response and changes in the levels of the innate immune accessory recognition proteins, soluble CD14 (sCD14) and lipopolysaccharide (LPS)-binding protein (LBP), were studied. Decreased milk output, induction of a febrile response, and increased acute phase synthesis of LBP were all characteristic of the systemic response to intramammary infection with either organism. Infection with either bacteria similarly resulted in increased milk levels of IL-1$\beta$, IL-8, IL-10, IL-12, IFN-$\gamma$, TNF-$\alpha$, sCD14, LBP, and the complement component, C5a. However, the duration of and/or maximal changes in the increased levels of these inflammatory markers were significantly different for several of the inflammatory parameters assayed. In particular, S. uberis infection was characterized by the sustained elevation of higher milk levels of IL-1$\beta$, IL-10, IL-12, IFN-$\gamma$, and C5a, relative to S. marcescens infection. Together, these data demonstrate the variability of the innate immune response to two distinct mastitis pathogens

Development of Methodologies to Reduce the DCAD of Hay for Transition Dairy Cows

Ration formulation for dairy cows prior to parturition must control the diet cation-anion difference (DCAD) if hypocalcemia and milk fever are to be avoided. One key to reducing hypocalcemia is to avoid incorporation of high K forages into the ration. The excessive K content of these forages can cause metabolic alkalosis in the cow and subsequently hypocalcemia and milk fever. Alfalfa and other cool season grasses are often used in dairy rations. Reducing K content of forages can be achieved by restricting K fertilization so that soils do not support luxury K consumption by the crops. Because K is the major cation contributing to high DCAD diets, an obvious solution is to limit K fertilization to avoid luxury consumption of K by the forage crop. However,some forages may have reduced yield and increased winter kill if K concentrations are \u3c 2.0%, particularly alfalfa. Thus, producing alfalfa with less than 2% K may not be profitable, especially in northern regions. In addition to decreasing forage K, the producer can also increase the Cl content of the forages, the resulting DCAD will be more favorable for the late gestation cow

Osteopenic Disease in Growing Pigs: Diagnostic Methods Using Serum and Urine Calcium and Phosphorus Values, Parathormone Assay, and Bone Analysis

This research was performed to evaluate the utility of several serum and urine parameters as well as bone ash and plasma parathormone assay to diagnose and monitor diet-related osteopenia in growing pigs. Five diets were tested as follows: calcium-deficient, phosphorus-replete; moderate-deficiency of calcium and phosphorus; marked deficiency of calcium and phosphorus; calcium replete, phosphorus deficient; and vitamin D deficient. Parameters monitored included serum calcium and phosphorus as well as ratios of urine calcium to creatinine, phosphorus to creatinine, calcium to phosphorus, and percent fractional excretions of calcium and phosphorus. Plasma parathormone (PTH) levels were monitored in 2 of 3 experiments. Osteopenic bone differences at necropsy were evaluated by bone density, percent ash, ash per milliliter bone, calcium per milliliter bone, and phosphorus per milliliter bone. Marked change in urine mineral parameters, especially the calcium-to-phosphorus ratio, typically occurred within 1 to 2 days of treatment and preceded significant change in serum mineral or plasma PTH by 2 to 3 weeks. When monitored, plasma PTH levels were elevated following treatment, which confirms the hyperparathyroid state induced by the test diets. Significant differences in bone mineralization between control and treatment diets at necropsy were generally observed. The results of this study indicate that the analysis of urine minerals offers an early, noninvasive technique to investigate diet-associated osteopenic disease in growing pigs, which can be supported further by bone mineral analysis at postmortem using techniques herein described. Several urine mineral reference intervals for application to field investigations are included. Research into application of similar techniques to evaluate calcium and phosphorus homeostasis in pigs of all ages, including gestating and lactating gilts and sows, appears warranted

Effects of Chloride Fertilization on Alfalfa Cation-Anion Content

Producing low potassium (K) forages has increased due to demand for such forages in the dairy business. In the month prior to calving, a fairly anionic diet is recommended in dairy cows to avoid milk fever, a term used for hypocalcemia, a deficiency in plasma calcium (Ca) at the onset of lactation in dairy cows. This bovine disease affects approximately 6 to 8% of all U.S. dairy cows annually, directly costing the dairy industry up to $200 million/year. As dairy cows enter the lactation stage prior to calving, large amounts of calcium leave the blood and enters milk faster than it can be replaced. This decreased calcium concentration in the blood lowers the pH, causing nerve disorders, muscle weakness, loss of appetite, paralysis, and subsequent death if not treated immediately. Treatment typically includes an intravenous dosage of a calcium solution, usually including a mixture of phosphorus (P), K, magnesium (Mg) and dextrose. Cationic diets, such as forages high in potassium (\u3e2.5%) are meant for the post-calving, lactation stage because of the dairy cow’s diet requirement in producing milk

Safety Of \u3ci\u3eBrucella Abortus\u3c/i\u3e Strain Rb51 In Black Bears

In two studies conducted from October 1999 to March 2000 and December 2000 to April 2001, adult black bears (Ursus americanus) were orally inoculated with 1.4–3.1X1010 colony-forming units (CFU) of Brucella abortus strain RB51 (SRB51, n=12) or 2 ml of 0.15 M NaCl solution (saline, n=11). We did not detect a difference (P\u3e0.05) in antibody titers to SRB51 in serum obtained before vaccination, at 8 wk after vaccination, or at necropsy at 21 or 23 wk after vaccination between SRB51-vaccinated and nonvaccinated bears. The SRB51 vaccine strain was recovered from tissues obtained at necropsy from one of six SRB51-vaccinated bears in study 1, but none of the six SRB51-vaccinated bears in study 2. Vaccination of black bears with SRB51 did not appear to influence (P\u3e0.05) reproductive performance

Dietary intake relative to cardiovascular disease risk factors in individuals with chronic spinal cord injury: a pilot study

BACKGROUND: The relationship between cardiovascular disease (CVD) risk factors and dietary intake is unknown among individuals with spinal cord injury (SCI). OBJECTIVE: To investigate the relationship between consumption of selected food groups (dairy, whole grains, fruits, vegetables, and meat) and CVD risk factors in individuals with chronic SCI. METHODS: A cross-sectional substudy of individuals with SCI to assess CVD risk factors and dietary intake in comparison with age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Dietary history, blood pressure, waist circumference (WC), fasting blood glucose, high-sensitivity C-reactive protein (hs-CRP), lipids, glucose, and insulin data were collected from 100 SCI participants who were 38 to 55 years old with SCI >1 year and compared to 100 matched control participants from the CARDIA study. RESULTS: Statistically significant differences between SCI and CARDIA participants were identified in WC (39.2 vs 36.2 in.; P < .001) and high-density lipoprotein cholesterol (HDL-C; 39.2 vs 47.5 mg/dL; P < .001). Blood pressure, total cholesterol, triglycerides, glucose, insulin, and hs-CRP were similar between SCI and CARDIA participants. No significant relation between CVD risk factors and selected food groups was seen in the SCI participants. CONCLUSION: SCI participants had adverse WC and HDL-C compared to controls. This study did not identify a relationship between consumption of selected food groups and CVD risk factors

Development of Methodologies to Reduce the DCAD of Hays for Transition Dairy Cows

Hypocalcemia (clinical and subclinical) create a major economic loss in early postpartum dairy cows. Ration formulation for dairy cows just prior to parturition must control the diet cation-anion difference (DCAD) if hypocalcemia and milk fever are to be avoided. The purpose of this research was to evaluate the use of specific fertilizer regimes for forages and evaluate their impact on mineral and DCAD levels in hays, as well as forage yields. The experimental design involved four different species of hay (alfalfa, bromegrass, orchardgrass, and reed canarygrass) fertilized with either CaCl2 or K2CO3 (designated K2O) alone or a combination (designated KCl) of both. In the plots not receiving K fertilization (Control and CaCl2) the K content of the plants regardless of species was lower relative to those receiving K (K2O and KCl). With regards to plant Cl content, the plots fertilized with CaCl2 alone or in combination with K2O resulted in substantial and at least a 2 fold elevations in tissue chloride in all the hays tested. DCAD was also significantly reduced with CaCl2 treatment alone and was reduced 50-75% in the Orchardgrass, Reed Canarygrass and Orchardgrass hays. The combination of K2O and CaCl2 resulted in an attenuation of this effect. CaCl2 treatment alone had no detrimental effect on yield when compared to Control plots. However, those plots fertilized with K (with or without Cl) had higher numerical yields than those not receiving K. These data suggest that withholding K fertilization in combination with Cl fertilization may be an effective means of increasing the Cl and ultimately decreasing the DCAD content of several species of hay without sacrificing yield. We will continue to monitor the effects of K and Cl fertilization on plant parameters during the FY05 and FY06 growing seasons. The effect of Cl fertilization on hay quality and palatability is currently under investigation