A whole-genome assembly of Drosophila

We report on the quality of a whole-genome assembly of Drosophila melanogaster and the nature of the computer algorithms that accomplished it. Three independent external data sources essentially agree with and support the assembly's sequence and ordering of contigs across the euchromatic portion of the genome. In addition, there are isolated contigs that we believe represent nonrepetitive pockets within the heterochromatin of the centromeres. Comparison with a previously sequenced 2.9- megabase region indicates that sequencing accuracy within nonrepetitive segments is greater than 99. 99% without manual curation. As such, this initial reconstruction of the Drosophila sequence should be of substantial value to the scientific community.     

Lead-210 and polonium-210 in biological samples from Alaska

The naturally occurring concentrations of lead-210 and polonium-210 in certain biological samples from Alaska are unusually high. The concentration processes are similar to those observed for artificially produced radioactive fallout. Concentrations of these nuclides are greater in Alaskan natives than they are in other United States residents.     

Bronchopleural fistula in the horse: A conduit of chronicity

Bronchopleural fistulas occur secondary to severe, chronic, bacterial pleuropneumonia in horses. Primary closure is rarely reported, and most bronchopleural fistulas resolve with time and prolonged antimicrobial administration. The case report in this issue describes primary closure with acrylate co-monomer glue. When faced with severe pleuropneumonia, clinicians can anticipate a good clinical outcome when infection can be eradicated which requires patience, persistence and the client’s financial fortitude.     

National beef market basket survey

Beef retail cases in supermarkets in 12 cities across the United States were surveyed for fat thickness measurements, cut representation, package weights and counts, and case space allocation. Randomly selected retail cuts were purchased and transported to Texas A&M University, where they were dissected into separable components. Samples of ground beef were obtained for chemical analysis. Over 42% of the beef retail cuts had no external fat, and approximately 75% of all cuts were boneless. The overall mean fat thickness for all retail cuts in the beef case was .31 cm, and the overall mean fat thickness for steaks and roasts from the major primals - chuck, rib, loin, and round - was .38 cm. The average percentage of separable lean was 79.0%, separable fat was 12.3%, and bone and connective tissue was 8.7%. Retail cuts had more than twice as much separable seam fat as separable external fat. Beef steaks and roasts had 27.4% less separable fat than values from USDA Agriculture Handbook 8-13. Of the ground beef surveyed, 37% was regular, 40% was lean, and over 22% was extra lean. Retail ground beef had approximately 10% less fat than values from USDA Agriculture Handbook 8-13.     

Investigation of a chronic feed-passage problem on a broiler farm in northwest Arkansas.

A commercial broiler farm with a history of poor feed conversion and chronic feed-passage problems was chosen for investigation. Chickens were taken from the broiler flock at specified intervals during growout and tested by virus isolation and enzyme-linked immunosorbent assay (ELISA) for avian reovirus. Abnormal tissue pathology was first seen in the broilers at 9 days of age and continued sporadically throughout the growout period. Antireovirus antibody levels began to increase at 24 days of age. Avian reovirus and avian adenovirus was recovered at different intervals starting at 17 and 31 days of age, respectively. One-day-old specific-pathogen-free chicks housed in filtered-air positive-pressure isolation units were inoculated with two inocula recovered from the field study. Avian reovirus was recovered from the tissues of both treatment groups using chick kidney cells. Significant weight differences were seen in one of the two treatment groups. This avian reovirus was given the name SS-412.     

CSF from a puppy with a cerebral vascular hamartoma

A 9-week-old puppy with refractory seizures and a dome-shaped head presented to the Mississippi State College of Veterinary Medicine Specialty Center for suspected hydrocephalus. Computerized tomography (CT) findings included transtentorial herniation and an intra-axial mass with dystrophic mineralization. Cerebrospinal fluid analysis revealed an increased nucleated cell count of 1100/μl (RI < 5/μl), erythrocyte count of 2.2 × 10⁶/μl, and markedly increased microprotein of 1939 mg/dl (RI < 30 mg/dl). On cytologic examination of the CSF, numerous erythrophagocytic, and hemosiderin-laden macrophages were observed, which indicated chronic active hemorrhage. Many neutrophils, macrophages, and lymphocytes that contained numerous intracytoplasmic, pleomorphic, bright yellow crystals were observed. Considering the ongoing hemorrhage, the crystals were presumed to be hematoidin. A biopsy with histopathology was performed on the intra-axial mass, and the results were consistent with a vascular hamartoma. We speculate that the formation of these crystals was related to the ongoing hemorrhage associated with the vascular hamartoma. Identification of these crystals may be useful to aid in the identification of chronic hemorrhage associated with vascular malformations or lesions within the central nervous system.     

Galaxy disruption in a halo of dark matter

The relics of disrupted satellite galaxies have been found around the Milky Way and Andromeda, but direct evidence of a satellite galaxy in the early stages of disruption has remained elusive. We have discovered a dwarf satellite galaxy in the process of being torn apart by gravitational tidal forces as it merges with a larger galaxy's dark matter halo. Our results illustrate the morphological transformation of dwarf galaxies by tidal interaction and the continued buildup of galaxy halos.     

An evaluation of anthelmintic properties,assessed using faecal nematode egg counts,of New Zealand native flax (Phormium tenax)

AIM: To investigate the anthelmintic properties of New Zealand native flax (Phormium tenax) for cattle, using a faecal egg count reduction test (FECRT).

METHODS: Twenty-six heifer calves with high (>300 epg) faecal nematode egg counts (FEC) were paired into two groups and fed either chopped flax leaves ad libitum, or barley straw at an equivalent dry matter (DM) rate, from Day 0–7; all were supplemented with 1.5 kg/head/day cereal feed supplement. On Days 8–10, all heifers were fed a common diet of 3.5 kg DM/ head/day barley straw and 1.5 kg/head/day cereal feed supplement. Heifers were weighed and faecal samples were collected on Days —6, 0, 7, and 10; samples were analysed in triplicate for FEC. The nutritive value of the flax and straw was analysed.

RESULTS: Both the flax and straw had low dry matter digestibility (DMD) and protein content. Although the flax-fed claves grew more than the controls, this may have been related to gut fill. Total daily faecal egg output was similar for flax and straw groups on Day 7 (14.7 vs 15.0 x 10⁶ eggs/day, respectively) and Day 10 (14.9 vs 15.1 x 10⁶ eggs/day, respectively). There was no difference in the change in FEC with time between the calves fed flax or straw diets.

CONCLUSION: Consumption of flax leaves did not reduce FEC in calves with a mixed nematode infection.