Suppression of ovarian progesterone production in dairy cows using an implant of GnRH-agonist (deslorelin) for the purpose of evaluating progesterone metabolism

OBJECTIVE: To evaluate the potential of an implant of a GnRH-agonist (deslorelin) to create a progesterone free animal suitable for studying progesterone (P4) metabolism in intact cows by measuring blood P4 and faecal P4 metabolites. METHODS: Experiment 1: Eighteen non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to one of three groups to study plasma P4 concentrations preceding an intravaginal insert. These groups comprised: i) a deslorelin group (GnRH-agonist implanted); ii) a PGF group receiving two injections of prostaglandin (PGF2alpha) 12 days apart; and, iii) an ovariectomised (OVX) group. An intravaginal device (CIDR) was inserted into the vagina of each animal and left in place for 11 days. Plasma P4 concentrations were measured during the study period. Experiment 2: Twelve non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to two groups: i) a deslorelin group (GnRH-agonist implanted); and ii) an ovariectomised group. Plasma P4 and faecal P4 metabolites (20-oxo-pregnanes, 20alpha-OH and 20beta-OH) were monitored for a period of 5 weeks. RESULTS: Experiment 1: Average plasma P4 concentration did not differ between the three groups (1.28, 1.43 and 1.55 ng/mL for deslorelin, OVX and PGF cows, respectively, P = 0.8) during the period of supplementation. Experiment 2: There was no difference in plasma P4 (mean plasma P4 < 0.02 ng/mL, P = 0.9) and faecal P4 metabolites between deslorelin and OVX cows 2 weeks after the implantation (P = 0.7). CONCLUSIONS: These data showed that a GnRH-agonist (deslorelin) implant may be used as an alternative to ovariectomy to create a progesterone free animal suitable for studying the metabolism of administered P4.     

Veterinary experiences as a Japanese prisoner of war and ex-POW along the Burma railroad from 1942 to January 1946

Summary As a prisoner of war the writer was working for nearly three years in different POW camps, and outside them, along the Burma railway from Thanbyuyzat in southern Burma up to Kanchanabury in Thailand. In the army of the Netherlands-Indian archipelago (KNIL) he had the military rank of reserve horse-doctor. In civilian life he was attached to the Veterinary Institute in Buitenzorg (now Bogor) as a veterinary bacteriologist. His task as a POW became that of meathygienist and supervisor of the living animals in the camps. In this function he diagnosed swine fever in growing pigs which had mainly been fed on the offal of the Japanese kitchen. The acute course and the pathological alterations observed during the post-mortem examinations were identical with those of the Southern-African type of the disease. In slaughter cattle the author diagnosed some cases of lung tuberculosis, one of anthrax, several of rinderpest, some of rhinal granulomatosis and one of foot and mouth disease. In chickens he found NCD (pseudo-fowlpest) and in ducklings a mortal disease which the author then called 'keeling disease' but which he many years later, recognized as virus hepatitis. As assistant bacteriologist and ex-POW he joined the British regimental hospital in Bangkok. Here he had the opportunity to assist the bacteriologist pathologist, Maj. C. R. Peck IMS / IAMC in diagnosing the first case of melioidosis in an ex-POW of the KNIL who died from the sub-acute infection, notwithstanding treatment in the hospital with sulfa-drugs and penicillin.     

Theileria orientalis: a review

Theileria orientalis (also known historically as T. sergenti and T. buffeli) is responsible for benign or non-transforming theileriosis, and exerts its major effect through erythrocyte destruction. The life cycle of T. orientalis is essentially similar to that of other Theileria species, except that the schizonts do not induce transformation and fatal lymphoproliferation. The pathogenesis of anaemia as a result of infection is not clearly established and may be multifaceted. Clinical signs of weakness, reluctance to walk and abortion are early but non-specific indications of disease, particularly if accompanied by a history of cattle being moved. Physical examination may reveal pallor (pale eyes, vaginal mucosa), pyrexia, and elevated heart and respiratory rates. T. orientalis is an economically important parasite of cattle in New Zealand, Australia and Japan, especially where naïve animals are introduced into an endemic area or in animals under stress. Increased awareness of the risks posed by the parasite is required to enable management practices to be implemented to minimise its impact.     

Presence of human Giardia in domestic,farm and wild animals,and environmental samples suggests a zoonotic potential for giardiasis

Giardia lamblia which parasitize humans belong to either of two genotypes, A or B, based on specific signature sequences in the 5' end of the small subunit (16S) ribosomal RNA (rRNA) gene. These two genotypes also were found in cysts from fecal samples of animal origin such as dogs, cats, some farm animals and wild animals. In addition, trophozoites recovered from cysts obtained from environmental samples belonged to these two genotypes as well, suggesting that the G. lamblia genotypes A and B are widespread and possibly zoonotic. Trophozoites were recovered from rats and these isolates might belong to another genotype of G. lamblia. Deer mice and one dog appeared to be parasitized by genotypes of Giardia with close affinity to G. microti. This species, therefore, also consists of a genotype complex.     

Naphthalophos combinations with benzimidazoles or levamisole as effective anthelmintics for sheep

Objective: To investigate the relative efficacy and safety of the anthelmintic naphthalophos in sheep, either given alone or in combination with benzimidazole (fenbendazole and albendazole) or levamisole anthelmintics.
Design: A parasitological study using faecal egg count reduction tests, a validating slaughter trial and field safety trials.
Procedure: Faecal egg count reduction tests were carried out on 13 farms. Naphthalophos and combinations of naphthalophos with levamisole and fenbendazole were included in the drench tests. On one property a controlled efficacy study was carried out to validate faecal egg count reduction test findings. In this trial, sheep were slaughtered 10 days after treatment and the remaining parasites recovered from the gastro-intestinal tract. Safety trials were carried out on eight farms where approximately 50 000 sheep were treated with naphthalophos and albendazole that were tank mixed in the backpack.
Results: The efficacy of naphthalophos alone in faecal egg count reduction tests ranged from 59 to 98% with one test showing 95% reduction. The efficacy of naphthalophos and levamisole ranged from 74 to 100%, with 5 farms showing 95% reduction. The efficacy of naphthalophos and fenbendazole ranged between 88 and 100% with 95% reduction achieved on 10 farms. The controlled efficacy study showed a good correlation between the faecal egg count reduction tests and numbers of parasites recovered, except for Nematodirus where the faecal egg count reduction tests overestimated efficacy. The mortality rate in the safety trials was 0.05%, with most fatalities occurring on one farm.
Conclusion: The combination of naphthalophos and fenbendazole was more effective than a combination of naphthalophos and levamisole, and will provide a sufficiently safe drench rotation option.     

Soil solution chemistry and element budgets of three Scots pine ecosystems along a deposition gradient in north-eastern Germany

Since 1993 we are studying three Scots pine ecosystems along a deposition gradient in north-eastern Germany (formerly GDR). Dramatic reductions of pollutant emissions are reported for the period since 1989/90. S-deposition is high at the sites Roesa and Taura (25 kg S ha^?1yr^?1) compared to Neuglobsow. Inputs of basic cations, especially Ca, by alkaline dust immissions decrease in the order Roesa > Taura > Neuglobsow. The soil solution data show high concentrations of Ca and SO₄ at Roesa decreasing drastically along the deposition gradient. The elevated pH values reflect the impact of alkaline dust deposition particularly in the organic surface layer at Roesa. The site Taura received less base cation deposition and is marked by the lowest pH values throughout the soil profile combined with increased Al concentrations in the solution of the mineral soil. Thus, the composition of the soil solutions clearly reflects the different deposition regimes of the past. The element budgets show that large amounts of base cations, sulfur, and, at Taura, also aluminum are actually released from the soils that were previously stored.     

Spatial Variability of Turbulent Mixing in the Abyssal Ocean

Ocean microstructure data show that turbulent mixing in the deep Brazil Basin of the South Atlantic Ocean is weak at all depths above smooth abyssal plains and the South American Continental Rise. The diapycnal diffusivity there was estimated to be less than or approximately equal to 0.1 x 10(-4) meters squared per second. In contrast, mixing rates are large throughout the water column above the rough Mid-Atlantic Ridge, and the diffusivity deduced for the bottom-most 150 meters exceeds 5 x 10(-4) meters squared per second. Such patterns in vertical mixing imply that abyssal circulations have complex spatial structures that are linked to the underlying bathymetry.