THE EFFECT OF COMMERCIAL TRAPPING ON RABBIT POPULATIONS

The effect of commercial trapping on two rabbit populations in West Wales, was investigated during 1946 to 1949. On two farms rabbits were caught alive in snares, marked and released just before trapping; the total number of rabbits marked, divided by the fraction of marked rabbits recovered in the trapped sample gave an estimate of the population before trapping started. Trapping usually removed 30–40 % of the rabbits present, a proportion compatible with a careful cropping of the population. At one farm, studied for 3 years, the population increased steadily.
Breeding was intense from January to June inclusive, and from weight and age distributions it was apparent that in 1948 and 1949 considerable breeding also occurred in autumn. The sex ratio varied around a mean of about 50%.
Data are given on movements, obtained from recapture records of zog marked animals. They suggest that rabbits probably forage over an area of not more than 150 yards in diameter. The records from recaptured marked animals indicate that the mean expectation of life is about 6 months.     

Fence-Line Contact Between Wild and Farmed Cervids in Colorado: Potential for Disease Transmission

Abstract: Direct and indirect contact between wild and farmed cervids along perimeter fences may play a role in transmission of diseases like chronic wasting disease (CWD), but no studies have quantified such interactions. At 9 high-fenced commercial elk (Cervus elaphus) farms in Colorado, USA, during October 2003 to January 2005, we used animal-activated video to estimate rates of fence-line use by wild cervids, rates of direct contact between farmed and wild cervids, and probability of direct contact when wild cervids were present. We recorded 8-fold-more wild elk per unit time than mule deer (Odocoileus hemionus) at fence lines. Depending on site, we recorded 0.66 to 46.90 wild elk per 1,000 hours of camera monitoring. We documented 77 interactions between wild and farmed elk involving naso-oral contact and no contact between wild mule deer and farmed elk. Rate of direct contact ranged from 0.00 to 1.92 direct contacts per 1,000 hours of camera monitoring among sites. Given recorded presence of wild elk, estimated probability of observing direct contact during a 2-minute video recording ranged from 0.00 to 0.11 among sites. Risk of direct contact was about 3.5 times greater for single woven-wire fence compared with offset electric fence attached to a single woven-wire fence. We observed no direct contact through double woven-wire fences. Because little is currently known about infection rates associated with infection mechanisms, we cannot infer a level of CWD infection risk from our results, but some form of double fencing should reduce potential for direct and indirect transmission of disease into or out of elk farms.     

The breeding biology of White-tailed Tropicbirds Phaethon lepturus at Cousin Island, Seychelles

During 1981–1983 the population of White-tailed Tropicbirds Phaethon lepturus at Cousin Island, Seychelles, bred aseasonally and asynchronously. The mean interval between consecutive successful breeding attempts was 273 days. Most individuals nested in the same site, and with the same partner, in successive attempts, but 7-5% of nest sites were used by more than one pair; 21 % of pairs which lost eggs, and 13% of those which lost chicks re-nested. Incubation lasted 40–41 days, with a mean incubation shift length of 6-6 days. Fledging periods varied between 67 and 89 days (mean 76-5 days). Mean fledging weight was not significantly greater than the average weight of breeding adults.
Fledging success was 36%. Many of the 39% of eggs which failed to hatch probably did so as a result of exposure to the sun's heat, following temporary desertion by adults which were themselves heat-stressed during incubation. Of the 41 % of chicks which died, most died young; many were probably killed by crabs Ocypode spp. Not more than 10% of all nest failures were due to nest site competition. A few chicks probably starved to death.
At the time of the study, both food and nesting sites were evidently in excess. A considerable increase in the size of the population will be possible before density-dependent control mechanisms begin to operate.     

Evaluation of fine needle aspiration of the male breast for the diagnosis of gynaecomastia

Fine needle aspiration of the male breast can present problems of diagnosis because the cytological presentation of gynaecomastia can be confused with that of adenocarcinoma. We reviewed breast aspirates from 24 male patients in order to determine the accuracy of cytology as a method of diagnosing gynaecomastia. Discrepancies were observed between the original cytology reports on one hand and the review cytology and biopsies on the other. Of the 24 aspirates from the male breast, the cytology was reported as negative in 16 cases, suspicious in three cases and malignant in five. In four cases of the negative group, a specific diagnosis of gynaecomastia was made. In two of the negative cases the subsequent biopsies revealed adenocarcinoma. Of the five cases reported on the original cytology as adenocarcinoma, two on review showed the features of florid gynaecomastia and this was confirmed on biopsy and three confirmed the initial diagnosis of adenocarcinoma. The cytological features of gynaecomastia which distinguish it from adenocarcinoma are discussed.     

Sperm structure and ultrastructure in the Hymenoptera (Insecta)

A light and electron microscopical survey of spermatozoan gross morphology and ultrastructure in the Hymenoptera is presented. Details are provided for the first time for members of the families Xyelidae, Argidae, Tenthredinidae, Diprionidae, Cephidae, Figitidae, Proctotrupidae, Diaprii- dae, Heloridae, Eurytomidae, Leucospidae, Perilampidae, Torymidae, Braconidae, Dryinidae, Sphecidae, Pompilidae and Vespidae. Spermatozoan length ranged from 8 μ m in some Braconidae to 500 μm in one chalcidoid. Considerable variation in gross morphology and ultrastructure were observed between taxa. Several phylogenetically informative characters were noted. Very small spermatozoa characterized most of the non-cyclostome subfamilies of Braconidae; spirally twisted axoneme and mitochondrial derivatives occur in the Eulophidae, Eurytomidae and Pteromalidae; spermatozoa with virtually indistinguishable head (nucleus and acrosome) regions characterized the Vespinae and Polistinae. The presence of well-developed spermatodesmata in the vas deferens and seminal vesicle characterize the Symphyta and were largely absent from other groups though they are occasionally present in some bees.     

A sporulation medium for Clostridium perfringens

A new solidified medium for inducing sporulation of Clostridium perfringens is described. The essential components of the medium are bile, bicarbonate and quinoline. The medium induced significant sporulation in all of 100 strains of Cl. perfringens isolated at random from human faecal specimens. The majority (94%) of strains sporulated profusely.     

Passive Haemagglutination Test for Anti-rhinovirus Antibodies

The use of chromic chloride as a coupling reagent has made it possible to coat red cells with rhinovirus protein. This is shown by immunofluorescence, electron microscopy and immunocolloidal experiments.     

Aminopeptidases from Plasmodium falciparum, Plasmodium chabaudi chabaudi and Plasmodium berghei

ABSTRACT. Using fluorogenic substrates and polyacrylamide gels we detected in cell-free extracts of Plasmodium falciparum, Plasmodium chabaudi chabaudi and Plasmodium berghei only a single aminopeptidase. A comparative study of the aminopeptidase activity in each extract revealed that the enzymes have similar specificities and kinetics, a near-neutral pH optima of 7.2 and are moderately thermophilic. Each has an apparent molecular weight of 80,000 ± 10,000, determined by high performance liquid chromatography on a calibrated SW500 column. Whilst the P. c. chabaudi and P. berghei activity co-migrate in native polyacrylamide gels, that of P. falciparum migrates more slowly. The three enzymes can be selectively inhibited by ortho -phenanthroline and are thus metallo-aminopeptidases; however, in contrast to other aminopeptidases the metal co-factor does not appear to be Zn²⁺.     

Trypanosoma Manulis N. Sp. From the Russian Pallas Cat Felis Manul

ABSTRACT. The morphology of Trypanosoma manulis n. sp. is described from living and stained specimens obtained from the blood of a Pallas cat, Felis manul , from Kazakhstan. the cat was also infected with a Hepatozoon sp. and feline immunodeficiency virus. the morphology of the trypanosome most closely resembles that of Trypanosoma mpapuense Reichenow and Trypanosoma heybergi Rodhain found in bats. Trypanosoma manulis does not grow well in conventional media, but co-culture with African green monkey kidney cells in Eagle's Minimum Essential Medium supplemented with 10% fetal calf serum at approximately 27° C resulted in luxuriant growth of trypanosomes. Under these growth conditions, epimastigotes adhered to the surface of the culture flask and to African green monkey kidney cells, as well as forming large rosettes. At 37° C, although growth was poor, transformation of the epimastigotes into the bloodstream forms occurred. This represents the first report of a trypanosome of the subgenus Megatrypanum in a felid.