Effects of stocking density and concentrate supplementation of grazing dairy cows on milk production, composition and processing characteristics

The effects on milk composition and processing characteristics of varying grass supply by changing stocking density and of offering a concentrate supplement were investigated. The experiment was conducted over 28 weeks of the lactation (April-October) using 48 spring-calved Friesian-Holstein cows. Three herds each of 16 cows were offered a restricted grass supply, a standard grass supply and a standard grass supply with a supplement of 3 kg concentrate/d. Treatment groups were grazed separately with a residence time of 3 d/paddock. Milk production, composition and processing characteristics such as renneting properties, ethanol stability and plasmin activity were measured weekly. Increasing stocking density above the standard system resulted in significant reductions in milk fat and protein yields, the concentrations of total protein, casein and whey proteins, and a deterioration in most processing characteristics. Imposing concentrate supplementation on the standard system increased total protein, casein and whey protein concentrations but generally did not improve processing characteristics except for ethanol stability. These results suggest that the standard grass supply in a rotational grazing paddock system can support efficient production of quality milk, and concentrate supplementation will not improve processing characteristics when an adequate supply of good quality herbage is available.

Effect of decreased milking frequency of cows in late lactation on milk somatic cell count, polymorphonuclear leucocyte numbers, composition and proteolytic activity

The effects of reducing the frequency of milking of cows in late lactation on milk somatic cell count (SCC), polymorphonuclear leucocyte (PMN) content, chemical composition and proteolytic activity were investigated. Intermittent milking is frequently practised by Irish farmers in late lactation, and the objective of this study was to determine whether this procedure could be linked to altered quality of milk. Seventeen Holstein Friesian cows in late lactation (> 215 d in milk) were assigned to two treatment groups, and were either milked twice a day until drying-off (control group) or milked intermittently as the yield fell (test group). Milk composition and enzymic characteristics were measured on two occasions. At the first sampling, day 7, test cows were on once daily milking and at the second, day 15, the test cows were being milked every second day. Milk yields were significantly lower in test than control animals and decreased between days 7 and 15 in both groups. Milk SCC and PMN levels were increased on reducing milking frequency and, at day 15, the increase was not linked to decreased milk yield. Milk lactose levels were significantly decreased and pH, alpha-lactalbumin levels, plasmin activity and plasminogen activity significantly increased by reducing milking frequency. In conclusion, reduced frequency of milking in late lactation leads to the production of milk that is abnormal in character and this may be linked to reduced quality of dairy products manufactured from such milk.

Growth hormone replacement does not improve psychological well-being in adult hypopituitarism: a randomized crossover trial

In order to examine the effect of growth hormone (GH) on psychological parameters in adult hypopituitarism, 20 adults were studied, mean age 47 years (range 20-69) with hypopituitarism and confirmed GH deficiency (GH < 3 micrograms/l following clonidine 0.15 mg/m2). Subjects were randomly allocated to either GH-up to 0.25 U/kg per week in daily doses) or placebo for 3 months before crossover to the opposite treatment arm. Psychological parameters were assessed by self-reported questionnaires (Disease Specific Questionnaire (DSQ), the Symptom Checklist-90 (SCL-90), and the Social Adjustment Scale (SAS)) at baseline and monthly intervals to the end of the trial. Both SAS and SCL-90 total scores showed a significant decline with respect to time (p = .03 and .013 respectively), although this was not a function of active treatment. DSQ showed a trend to decline (p = .06), but no effect of active treatment. None of the subscale components of the SCL-90 showed any significant change on active treatment. Improvement in psychological parameters occurs as a function of enrolment to a clinical trial, rather than active GH replacement in adult hypopituitarism.

Plasma cortisol, PRL, ACTH, AVP and corticotrophin releasing hormone responses to direct current cardioversion and electroconvulsive therapy

OBJECTIVE

We aimed to evaluate and contrast the hypothalamo-pituitary-adrenal (HPA) response to direct current (DC) cardioversion and electroconvulsive therapy (ECT).

SUBJECTS

Six male subjects (mean age 61.2 years, range 46-74) with chronic atrial fibrillation were selected for cardioversion. Six subjects with depression (one male, five female; mean age 43.2 years, range 31-59) were selected for ECT. Those taking glucocorticoid drugs, opiates or beta-adrenoceptor antagonists were excluded.

MEASUREMENTS

Patients attended for serial blood sampling on the day of cardioversion or ECT, and for an equivalent time period on a control day at least one week before. Intravenous propofol was given to each subject for anaesthesia on the day of cardioversion or ECT. On both study and control days, blood samples were taken at -30, -15, 0 (just prior to cardioversion or ECT), +5, +10, +15, +30, +60, +90 and +120 minutes for assay of cortisol, PRL, ACTH, AVP and CRH.

RESULTS

For cardioversion: plasma cortisol increased from 252.5 +/- 39.8 to a maximum of 721.3 +/- 50 nmol/l at 30 minutes (P < 0.0001 compared with control day). ACTH increased from 12.8 +/- 2.8 to a maximum of 64 +/- 14 pmol/l at 5 minutes (P < 0.0001 compared with control day). AVP increased from 6.6 +/- 3.3 to a maximum of 42.9 +/- 16 pmol/l at 5 minutes post-cardioversion (P < 0.005 compared with control day). PRL increased from 141 +/- 28 mlU/l to a maximum of 873 +/- 219 mlU/l at 10 minutes (P < 0.001 compared with control day). There was no significant difference in CRH responses between cardioversion and control days. There was no significant correlation between total electrical energy delivered and maximum ACTH and AVP responses (R = 0.54 and -0.13, respectively). For ECT: on the day of ECT plasma cortisol increased from 419.5 +/- 25.9 to a maximum of 614.7 +/- 26.9 nmol/l (P < 0.002 compared with control day). ACTH increased from 22.7 +/- 6.2 to a maximum of 77.8 +/- 19.1 pmol/l (P < 0.0003 compared with control day). PRL increased from 771 +/- 317 to a maximum of 3152 +/- 703 mlU/l (P < 0.001 compared with control day, and significantly greater than the peak response to cardioversion, P < 0.03). AVP increased from 13.0 +/- 10.8 to a maximum of 35.1 +/- 5.6 pmol/l (P < 0.02 compared with control day). There was no significant difference in CRH responses between ECT and control days. Peak cortisol and ACTH responses did not differ significantly between ECT and cardioversion. Baseline cortisol levels, however, were significantly higher in the depressed group compared with the cardioversion group, P < 0.02, but not ACTH or AVP.

CONCLUSION

Significant hypothalamic-pituitary-adrenal activation and PRL release occur in response to both cardioversion and ECT. AVP may have an important role in mediating the acute ACTH response to electrical stimulation.

Silicosis and workers' compensation in New Jersey

The employer is expected to maintain responsibility for health care expenses and lost income that result from occupational injury and illness through the workers' compensation insurance system. However, financial support for individuals with occupational illnesses, especially those with long latency, is often from sources other than workers' compensation. Silicosis, a well defined, chronic, occupational lung disease, can be viewed as a sentinel for the inadequacy of the public policy to compensate workers for chronic occupational lung disease. Three hundred twenty-nine patients with confirmed silicosis were identified by the silicosis surveillance program in the New Jersey Department of Health using source data from 1979 through 1992. One hundred seventy-seven of these individuals provided information on the status of any compensation claims against their employer. Only 31% of these patients stated that a claim had been filed; 84% of those whose claims were settled were awarded payments. Severity of radiologic findings was not associated with the likelihood of filing a claim or with being awarded a payment; whereas, smoking was associated with these outcomes. The implications of these findings for the health care system are discussed.

The distribution of rare alleles

Population geneticists have long been interested in the behavior of rare variants. The definition of a rare variant has been the subject of some debate, centered mainly on whether alleles with small relative frequency should be considered rare, or whether alleles with small numbers should be. We study the behavior of the counts of rare alleles in samples taken from a population genetics model that allows for selection and infinitely-many-alleles mutation structure. We show that in large samples the counts of rare alleles--those represented once, twice, ...--are approximately distributed as a Poisson process, with a parameter that depends on the total mutation rate, but not on the selection parameters. This result is applied to the problem of estimating the fraction of neutral mutations.

Type I hypersensitivity reactions in intestinal mucosae from rats infected with Fasciola hepatica

Type I hypersensitivity reactions in the intestinal tract of sensitized animals may contribute to resistance to reinfection with Fasciola hepatica. Colonic mucosae isolated from previously infected rats were voltage clamped in Ussing chambers. Antigen was prepared as a crude homogenate from adult liver fluke. Assay of serum antibodies against fluke antigen confirmed sensitization. Antigen challenge evoked a rapid onset, transient inward current in sensitized but not in control preparations. Chloride secretion accounted for at least part of the response since the loop diuretic bumetanide reduced the effect of antigen by 61%. Anti-rat IgE mimicked the response to antigen and desensitized tissues to subsequent antigen challenge. Local synthesis of eicosanoids may mediate the response to antigen since the cyclo-oxygenase inhibitor piroxicam reduced the response by 76%. In contrast, mepyramine which is a histamine receptor antagonist did not alter the ion transport response evoked by antigen. Tetrodotoxin reduced the response to antigen by 53% implicating intrinsic neurons within the lamina propria as effector cells in the responses of this tissue to antigen. We propose that antigen stimulation of electrogenic chloride movement and consequent fluid secretion in vivo may contribute to a local effector mechanism in prevention of reinfection of previously sensitized hosts.

Leiomyosarcoma of the femoral vein

Soft-tissue masses uncommonly completely occlude or engulf a major vessel. Complete occlusion of a major vein suggests that the mass originates in the wall of the vein. Such tumours are rare, the most frequently encountered type being leiomyosarcoma. The authors present a case of leiomyosarcoma of the femoral vein.

Identification of phosphorylcholine containing antigens of Fasciola hepatica--successful tolerization against this epitope in experimental animals

Phosphorylcholine containing antigens have been identified in the parasite Fasciola hepatica by immunoblotting and ELISA. Immunoblots probed with polyclonal and monoclonal antibodies indicate that the majority of antigens identified in both the immature and mature parasite contain both phosphorylcholine and non-phosphorylcholine epitopes. One antigen of 58 kDa appears to contain predominantly PC epitopes or at least this epitope is the major one responded to by host animals. Successful immunotolerization against the epitope PC was achieved by injecting the PC conjugate, ovalbumin PC, into neonatal rats. Immunotolerization against PC resulted in a 25% reduction in worm burden upon subsequent infection with Fasciola hepatica.

Prevalence of three bulimia syndromes in the general population

Prevalence of bulimia was estimated from a cross-sectional general population survey of 1498 adults, using the Diagnostic Interview Schedule (DIS) administered by trained lay interviewers. Lifetime prevalence of the DSM-III syndrome in adults aged 18-64 was 1.0% and this was concentrated in young women: in women aged 18-44 lifetime prevalence was 2.6%, and 1.0% currently had the disorder. Based on clinicians' reinterviews of random respondents and identified and marginal cases, the prevalence of current disorder using criteria for draft DSM-III-R bulimia was 0.5%, for DSM-III it was 0.2%, and for Russell's Criteria bulimia nervosa 0.0%. A strong cohort effect was found, with higher lifetime prevalence among younger women, which is consistent with a growing incidence of the disorder among young women in recent years. Although elements of the syndromes were so common as to suggest that dysfunctional attitudes to eating and disturbed behaviour surrounding eating are widespread, there was little evidence of the bulimia syndrome having become an epidemic on the scale suggested by early reports.

Basket removal of intraatrial catheter after liver transplantation: technical note

A fragment of an intravenous catheter, lodged in the right atrium of a patient after a recent liver transplant, was removed percutaneously. Extra care is needed in such patients if the transfemoral approach is used. Reasons for the additional precautions are discussed and a case history is provided.

Is knowing the age-order of alleles in a sample useful in testing for selective neutrality?

The most powerful, and most frequently used, test of selective neutrality, based on data consisting of observed allelic frequencies in a sample of genes at some locus, is the procedure of G. A. Watterson. This procedure uses the sample homozygosity F* as the test statistic, and in effect leads to rejection of the hypothesis of selective neutrality if the observed value of F* differs significantly from neutral theory expectations. The homozygosity statistic is invariant under relabeling of the alleles and thus cannot use any further information on the alleles which might be available. We present results which suggest that information concerning the age order of the alleles cannot be used to provide a more powerful testing procedure than that of Watterson.