Cows (n = 139) were sampled within 17 d postpartum and monthly thereafter to examine dynamics of mammary infections and relationships between infection status, milk yield, SCC, NAGase activity, and chloride concentration. Forty-eight and 67% of cows and 19.5 and 30.5% of quarters were infected at first test and lactation end, respectively, with 51% of all infections present at first test. Coagulase-negative staphylococci accounted for 67 and 65% of first test and total infections with 85% persisting to lactation end. Animals with coagulase-negative staphylococci infections had significantly elevated quarter SCC and NAGase activity and a decrease of 821 kg mature equivalent lactation milk production compared with uninfected animals. Clinical cases with no bacterial isolation or major pathogen infections were associated with significant elevations in bucket and quarter milk SCC, NAGase activity, chloride concentration in quarters, and a decrease of 1153 kg mature equivalent lactation milk production as compared with uninfected animals. Correlations between milk production and in SCC and ln NAGase and between ln SCC and ln NAGase were -.15, -.25, and .55 (-.23, -.28, and .41 for first lactation only).
Neurology. 2002;58:1227‐1233. BACKGROUND: Previous single voxel (31)P MRS pilot studies of migraine patients have suggested that disordered energy metabolism or Mg(2+) deficiencies may be responsible for hyperexcitability of neuronal tissue in migraine patients. These studies were extended to include multiple brain regions and larger numbers of patients by multislice (31)P MR spectroscopic imaging. METHODS: Migraine with aura (MWA), migraine without aura (MwoA), and hemiplegic migraine patients were studied between attacks by (31)P MRS imaging using a 3‐T scanner. RESULTS: Results were compared with those in healthy control subjects without headache. In MwoA, consistent increases in phosphodiester concentration [PDE] were measured in most brain regions, with a trend toward increase in [Mg(2+)] in posterior brain. In MWA, phosphocreatine concentration ([PCr]) was decreased to a minor degree in anterior brain regions and a trend toward decreased [Mg(2+)] was observed in posterior slice 1, but no consistent changes were found in phosphomonoester concentration [PME], [PDE], inorganic phosphate concentration ([Pi]), or pH. In hemiplegic migraine patients, [PCr] had a tendency to be lower, and [Mg(2+)] was significantly lower than in the posterior brain regions of control subjects. Trend analysis showed a significant decrease of brain [Mg(2+)] and [PDE] in posterior brain regions with increasing severity of neurologic symptoms. CONCLUSIONS: Overall, the results support no substantial or consistent abnormalities of energy metabolism, but it is hypothesized that disturbances in magnesium ion homeostasis may contribute to brain cortex hyperexcitability and the pathogenesis of migraine syndromes associated with neurologic symptoms. In contrast, migraine patients without a neurologic aura may exhibit compensatory changes in [Mg(2+)] and membrane phospholipids that counteract cortical excitability. Comment: If the theory of hyperexcitability of migraine brain is correct, basic scientists will need to find clear markers for the neuronal abnormalities that underlie this excitability. Using their techniques, these researchers could not find such markers. SJT
Somatic cells in milk include epithelial cells from the gland and leukocytes from the blood. Epithelial cells are elevated in very early and late lactation. Leukocytes increase during mastitis infection or injury. They have phagocytic properties and combat invading organisms. Mean somatic cell counts of each milking over a 1-month period for cows with no udder infection, non-pathogens, or pathogens, were 169,500, 225,800, and 997,800 cells per ml, with coeffecients of variation of 94, 66, and 82%. Advanced age, late lactation, and a previous history of mastitis are related to elevated cells. Milk loss in subclinical mastitis is related to somatic cell counts. On a quarter basis, loss started at 500,000 cells per ml, progressed to 7.5% at 1 million, and 30% at 5 million. In cell counting programs associated with monthly testing of individual cows, those cows with two cell counts over 1 million cells per ml produced over 1,000 pounds of milk per lactation less than other cows in the same lactation whose cell count never exceeded 500,000 per ml. Use of cell counting on an individual cow basis improves its usefulness as a management tool for the dairyman compared to bulk tank counts. Literature data suggest the following changes in the milk composition from quarters definitely positive to mastitis screening tests based on somatic cell counts compared to normal quarters (values represent percent of normal): total solids (92), lactose (85), fat (88), total protein (100), caseins (82), whey protein (162), chloride (161), sodium (136), potassium (91), pH (105), lipase activity (116), and acid degree value (183).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.