Effect of supplement crude protein concentration on milk production over the main grazing season and on nitrogen excretion in late-lactation grazing dairy cows

The objectives of this study are to evaluate the effects of (1) a potential interaction between supplement crude protein (CP) concentration and differing cow genotypes on milk production, (2) differing cow genotypes on milk production, and (3) decreasing the supplement CP concentration on milk production and N excretion during the main grazing season within a spring-calving herd. A 2 × 2 factorial arrangement experiment, with 2 feeding strategies [14%; n = 30 (lower CP; LCP) and 18%; n = 28 (higher CP; HCP) CP concentrate supplements] offered at varying levels according to pasture availability and days in milk (DIM) was conducted over the main grazing season from April 3 to September 3, 2019, at University College Dublin Lyons Farm. Cows were also grouped into 2 genotype groups: lower milk genotype; n = 30 [LM; milk kg predicted transmitting ability (PTA): 45 ± 68.6 (mean ± SD); fat kg PTA: 10 ± 4.9; and protein kg PTA: 7 ± 2.3] and higher milk genotype; n = 28 [HM; milk kg PTA: 203 ± 55.0; fat kg PTA: 13 ± 3.8; and protein kg PTA: 10 ± 2.4]. A total of 46 multiparous and 12 primiparous (total; 58) Holstein Friesian dairy cows were blocked on parity and balanced on DIM, body condition score, and Economic Breeding Index. Cows were offered a basal diet of grazed perennial ryegrass pasture. The N partitioning study took place from August 25 to 30, 2019 (187 ± 15.2 DIM). No interactions were observed for any milk production or milk composition parameter. No effect of supplement CP concentration was observed for any total accumulated milk production, daily milk production, or milk composition parameter measured. The HM cows had increased daily milk yield (+1.9 kg), fat and protein (+0.15 kg), and energy-corrected milk (+1.7 kg), compared with the LM cows. Furthermore, HM cows had decreased milk protein concentration (-0.1%) compared with LM cows. For the N partitioning study, cows offered LCP had increased pasture dry matter intake (PDMI; +0.9 kg/d), dietary N intake (+0.022 kg/d), feces N excretion (+0.016 kg/d), and decreased N partitioning to milk (-2%), and N utilization efficiency (-2.3%). In conclusion, offering cows LCP had no negative influence on milk production or milk composition over the main grazing season where high pasture quality was maintained. However, any potential negative effects of offering LCP on milk production may have been offset by the increased PDMI. Furthermore, offering cows LCP decreased N utilization efficiency due to the higher PDMI and feed N intake associated with cows on this treatment in our study.s.

Combined infection of Norwalk-like virus and verotoxin-producing bacteria associated with a gastroenteritis outbreak

Detection of multiple pathogens, particularly a combination of viruses and bacteria, is infrequently documented in outbreaks of gastroenteritis. This paper reports the presence of Norwalk-like virus (NLV) and enterohaemorrhagic verotoxin-producing Escherichia coli in one individual, and NLV and verotoxin-producing Aeromonas sobria in another individual, both part of a large gastroenteritis outbreak. The causes of gastroenteritis in such outbreaks may be more complex than previously thought.

Cryptosporidiosis in patients with AIDS

Cases of cryptosporidiosis in patients with the acquired immunodeficiency syndrome (AIDS) residing in Melbourne over a 6-year period (1990-1995) are described. During this period 85 cases occurred, while 979 new AIDS diagnoses were notified. Over this period temporal clustering in cryptosporidial detection was evident (P=0.007), but the pattern was not statistically associated with the season, rainfall (P=0.88), mean average maximal temperature (P=0.15) or mean average minimal temperature. Further studies should identify these risk factors and provide an opportunity to prevent this devastating disease.

Primary follow-up care in a multidisciplinary setting enhances catch-up growth of very-low-birth-weight infants

OBJECTIVE

To determine the impact of multidisciplinary primary care follow-up, which included the services of a registered dietitian, on growth outcomes of very-low-birth-weight (VLBW) infants.

DESIGN

Data were obtained retrospectively from medical records. Forty-two infants receiving follow-up care on an as needed basis from the general pediatric clinic were compared with 33 infants receiving multidisciplinary follow-up care that included routine nutrition intervention from the comprehensive care clinic. Comparisons were made in weight, length, and head circumference measurements; growth rates; and catch-up growth (defined as > or = 5th percentile on growth charts of the National Center for Health Statistics attained by 12 months growth-corrected age).

SUBJECTS

VLBW infants (< or = 1,500 g at birth) were selected from both follow-up groups.

STATISTICAL ANALYSIS

Chi 2 Analysis compared the proportions of infants in each group who achieved catch-up growth. Unpaired t tests compared group means in weight, length, and head circumference measurements and growth rates.

RESULTS

The two groups differed significantly in the number of infants exhibiting catch-up growth for length and head circumference. At 8 months growth-corrected age, 7 (28%) of the general pediatric clinic infants were at the 5th percentile or greater for length compared with 21 (64%) of the comprehensive care clinic infants (P < .01); 15 (60%) of the general pediatric clinic group and 30 (91%) of the comprehensive care clinic group were at the 5th percentile or greater for head circumference (P < .05). At 12 months growth-corrected age, 12 (57%) of the general pediatric clinic infants and 26 (87%) of the comprehensive care clinic infants were at the 5th percentile or greater for length (P < .05); 11 (52%) of the general pediatric clinic infants and 27 (90%) of the comprehensive care clinic infants were at the 5th percentile or greater for head circumference (P < .05).

APPLICATIONS

Multidisciplinary primary care follow-up that includes the services of a registered dietitian for nutrition intervention can enhance the catch-up growth of VLBW infants through 12 months growth-corrected age.

In vitro growth of the microsporidian Septata intestinalis from an AIDS patient with disseminated illness

A new species of microsporidian, Septata intestinalis, was recently recognized as an opportunistic pathogen of AIDS patients. In this study, it was cultured from the nasopharyngeal aspirate of a human immunodeficiency virus type 1-infected patient with disseminated microsporidiosis. In human embryonic lung cells exposed to S. intestinalis, a cytopathic effect appeared within 28 days as foci of rounded up cells. Thin-section electron microscopy showed a variety of developmental stages of the microsporidium within parasitophorous vacuoles. In monocyte-derived macrophages, evidence of infection and development of the parasite was demonstrated by light and electron microscopy. In both infected human embryonic lung cells and monocyte-derived macrophages, a network of septa separated individual spores. Partial sequencing of the RNA small-subunit gene (16S rDNA gene) confirmed the identity of this parasite as S. intestinalis. This is the first report of the isolation of S. intestinalis in vitro and provides evidence that the parasite can be disseminated by macrophages.

A new trichrome-blue stain for detection of microsporidial species in urine, stool, and nasopharyngeal specimens

Detection of microsporidia in clinical specimens has relied on electron microscopy, histology, or staining. This article describes further alterations to the modified trichrome staining method which make it easier to identify microsporidial spores. The changes are a decrease in the phosphotungstic acid level and the substitution of a colorfast counterstain, aniline blue, for the fast green of the original stain. The modified stain provides good contrast between microsporidial spores and background material including human and fungal cells. Stool specimens from 139 human immunodeficiency virus-seropositive patients revealed that 5 patients were infected with Enterocytozoon bieneusi and 6 patients had larger spores. Thin-section electron microscopy of the larger spores showed a structure consistent with that of either Encephalitozoon or Septata species. Three of the patients with Encephalitozoon- or Septata-like species had disseminated infection, with spores detected in nasopharyngeal aspirates and urine samples.

Occurrence of invasive thymoma after thymectomy for myasthenia gravis: report of a case

We report the occurrence of an invasive thymoma following a median sternotomy with removal of a normal involuted thymus in a patient with myasthenia gravis and stress the prompt reevaluation of post-thymectomy patients who have an initial good response and then deteriorate.

Concurrence of limb girdle muscular dystrophy and myasthenia gravis

We describe a case of limb girdle muscular dystrophy with associated myasthenia gravis. This association has not been previously noted in the literature. The unusual feature of the case was that symptoms coexisted for several years before a correct diagnosis was made. The diagnosis was based on the clinical picture and the results of the muscle biopsy and electrophysiologic testing. This case serves to illustrate the fact that a separate problem should be considered when the clinical picture is not compatible with the underlying diagnosis.

Neonatal Citrobacter meningitis: pathogenesis of cerebral abscess formation

In 2 premature infants with brief survival, the major pathological feature of Citrobacter meningitis consisted of vasculitis and infarction with necrosis and liquefaction of large portions of the white matter of the hemispheres. Areas of decreased density demonstrated on computed tomographic head scan represented infarction with necrosis, liquefaction, and cavitation and not a classic abscess. This finding has clinical significance, because surgical drainage of liquefied infarcts is rarely indicated and could further damage the relatively preserved cortex.

Meningococcal meningitis in children: clinical comparison of disease produced by the minor and major serologic groups of Neisseria meningitidis

Since 1972, there has been an increased incidence of meningococcal disease due to the minor serologic groups, "serogroups," of Neisseria meningitidis. Few cases, however, have been reported in pediatric patients. We present 24 cases of meningococcal meningitis, ten of them (42%) due to serogroups X, Y, and Z N meningitidis. We believe these cases to be the largest group of pediatric patients with such meningitis thus far reported. The clinical disease produced by the minor serogroups was indistinguishable from that produced by the major serogroups. Our experience supports previous published reports that severe meningococcal disease does occur with the minor serogroups of N meningitidis, and this increasing incidence may be of major importance if vaccination programs are to be effective in controlling epidemic meningococcal disease.

Aflatoxin B1; its role in the etiology of Reye's syndrome

Seven cases of Reye's syndrome in which aflatoxin B1 was isolated from the blood or liver or both are presented. In two cases aflatoxin B1 was found in the blood during the acute phase of the disease; a finding not previously reported. In six cases aflatoxin B1 was recovered from autopsy specimens of liver. A number of case reports linking aflatoxin B1 to Reye's syndrome have appeared in the literature but until now only one case had been reported from the United States. Aflatoxin B1 and its possible role in the etiology of Reye's syndrome is discussed. It is concluded that Reye's syndrome is the result of multiple interrelated factors.

Enterotoxin-producing Escherichia coli and diarrhoea among newborn babies in Darwin

Specimens of Escherichia coli O119B14 isolated from 13 newborn babies during an outbreak of diarrhoea in Darwin Hospital were tested for their ability to produce enterotoxin. Of the 13 isolates tested none was found to produce heat-labile enterotoxin. However, isolates from two of the five diarrhoeal faecal specimens were found to produce moderate levels of heat-stable enterotoxin (ST). It seems like that ST-producing strains of E. coli were responsible for the diarrhoea.

Neurological evaluation of the newborn

The neurological examination is an integral part of the evaluation of the newborn infant. In too many instances the infant is dismissed from the nursery as 'normal' when,in fact, little or no effort has been expended to determine the body's neurological status. The neurological deficits overlooked often do not become overt until a much later age. Early detection can prevent the mental anguish that plagues the parents who must be told that their 'normal' infant has significant neurological problems. In some instances early diagnosis may lead to a better ultimate prognosis. We have presented a simple scheme for the neurological evaluation of the full-term infant and hope that it will be useful in encouraging pediatricians to assess neurological status.