The distribution of 35S-sulfadiazine and 14C-trimethoprim in rainbow trout, Salmo gairdneri.

The distribution of ³⁵S-labelled sulfadiazine and ¹⁴G-labelled trimethoprim was studied in rainbow trout by use of whole body autoradiography and liquid scintillation. As compared to mammals, gastrointestinal absorption and elimination were slow. Accumulation in the skin and the uveal tract of the eye was observed for both drugs tested. The results also indicated that the bile was an important route of excretion. Considerable radioactivity was still present in the skin at 144 hr. survival time.     

Parapoxvirus papillomatosis in the muskoxen (Ovibos moschatus): genetical differences between the virus causing new outbreak in a vaccinated herd, the vaccine virus and a local orf virus

Since 1981 a domesticated muskoxen herd had been successfully vaccinated against papillomatosis with homogenated, glutaraldehyde inactivated papilloma tissue. In the fall of 1985 a new clinical outbreak of disease occurred, affecting previously infected as well as vaccinated animals. The purification of parapox virions directly from papilloma tissue and orf scabs collected in a local sheep farm was followed by restriction endonuclease analysis of viral DNA. The morphological identity of purified virus was controlled by electron microscopy. Comparison of restriction endonuclease digests (10 different enzymes) by gel electrophoresis demonstrated that the muskoxen parapoxvirus from the new outbreak 1985 differed considerably from the 2 other isolates (muskoxen 1981 and local orf). The latter viruses demonstrated a high degree of homology, but differences were evident after digestion with the enzyme EcoRI. During metrizamide gradient purification minor bands containing morphologically intact virions were isolated in addition to the major fractions. The restriction enzyme digests indicated that the virions of the minor bands differed from those in the major bands.     

Important characteristics of some browse species in an agrosilvopastoral system in West Africa

Three browse species, Afzelia africana Sm., Khaya senegalensis (Desv.) A. Juss., and Pterocarpus erinaceus Poir. were investigated as agroforestry system components in a subhumid zone of West Africa. The foliation, flowering and fruiting of ten trees per species were recorded every 15 days for 2 years. The total foliage biomass at maximum availability was determined by complete pruning of 75 trees. The chemical composition of the foliage and the proportion of trees pruned on the pasture were determined. The phenological phases of the species began in the dry season and ended at the end of the rainy season. Afzelia africana and Pterocarpus erinaceus were totally defoliated during 2–6 weeks while K. senegalensis replaced the foliage progressively and earlier. The crude protein content was significantly different (123 g, 102 g and 92 g kg⁻¹ dry matter (DM) for Afzelia africana, Pterocarpus erinaceus and K. senegalensis, respectively). The foliage biomass per tree of K. senegalensis, Pterocarpus erinaceus and Afzelia africana differed significantly (41 kg, 30 kg and 21 kg DM ha⁻¹, respectively) while Pterocarpus erinaceus had the highest available foliage biomass per ha. The trees of Afzelia africana were intensively pruned. There was a significant relationship found between foliage biomass and circumference of the crown for Afzelia africana (R ² = 82%) and Pterocarpus erinaceus (R ² = 81%). Relationships were also found between circumference of the branches and foliage biomass. In conclusion, the trees are important potential fodder and nitrogen sources for animals in the agrosilvopastoral system and the phenological differences make the fodder available during a long period of time.     

Carbon and nitrogen in forest floor and mineral soil under six common European tree species

The knowledge of tree species effects on soil C and N pools is scarce, particularly for European deciduous tree species. We studied forest floor and mineral soil carbon and nitrogen under six common European tree species in a common garden design replicated at six sites in Denmark. Three decades after planting the six tree species had different profiles in terms of litterfall, forest floor and mineral soil C and N attributes. Three groups were identified: (1) ash, maple and lime, (2) beech and oak, and (3) spruce. There were significant differences in forest floor and soil C and N contents and C/N ratios, also among the five deciduous tree species. The influence of tree species was most pronounced in the forest floor, where C and N contents increased in the order ash = lime = maple < oak = beech ? spruce. Tree species influenced mineral soil only in some of the sampled soil layers within 30 cm depth. Species with low forest floor C and N content had more C and N in the mineral soil. This opposite trend probably offset the differences in forest floor C and N with no significant difference between tree species in C and N contents of the whole soil profile. The effect of tree species on forest floor C and N content was primarily attributed to large differences in turnover rates as indicated by fractional annual loss of forest floor C and N. The C/N ratio of foliar litterfall was a good indicator of forest floor C and N contents, fractional annual loss of forest floor C and N, and mineral soil N status. Forest floor and litterfall C/N ratios were not related, whereas the C/N ratio of mineral soil (0–30 cm) better indicated N status under deciduous species on rich soil. The results suggest that European deciduous tree species differ in C and N sequestration rates within forest floor and mineral soil, respectively, but there is little evidence of major differences in the combined forest floor and mineral soil after three decades.     

Effects of different step‐wise temperature increment regimes during egg incubation of Atlantic cod (Gadus morhua L.) on egg viability and newly hatched larval quality

We carried out an experiment to determine how rapidly the early incubation temperature of Atlantic cod eggs can be increased without affecting normal embryonic development and hatching. Atlantic cod eggs were incubated at a constant low temperature (4.5 ± 0.5°C; T5 – control) and four temperature increment treatments where the temperatures were increased stepwise from 4.5°C at zygote stage to 9.5 ± 05°C (T1‐8 h, T2‐32 h, T3‐64 h and T4‐96 h). Embryonic cell symmetry, embryonic mortality, hatching success and larval skeletal abnormalities, length and yolk sac volume were recorded. Larval samples were also taken at hatch for histological analysis. Except for higher egg mortality and lower hatching success in the T1, the differences among experimental groups were minor. Cell asymmetries and embryo mortalities were not significantly different between the control and T2–T4 treatment groups. Control larvae were significantly longer and had smaller yolk reserves at hatch than T1–T4 larvae and larvae from T2 had the largest yolk reserves. Tissue and organ histology of hatched larvae were similar. Considering embryonic cleavage pattern, hatching success and larval morphology and histology, a gradual increment of temperature in 32 h seems to be the better choice for future developmental programming studies in Atlantic cod.     

Clinical and biochemical changes in 53 Swedish dogs bitten by the European adder - Vipera berus

Background

Every year many dogs in Sweden are bitten by Vipera berus, the only venomous viper in Sweden. This prospective study investigated clinical signs, some biochemical parameters, treatment, and progress of disease after snakebite in 53 dogs. Effects of treatment with and without glucocorticoids were evaluated.

Methods

All fifty-three dogs bitten by Vipera berus were examined the same day the dog was bitten and the next day. Two more examinations during 23 days post snake bite were included. Creatinine, creatine kinase (CK), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), alkaline phosphatase (ALP) and bile acid results were followed through 3 to 4 samplings from 34 of the dogs.

Results

All dogs had variable severity of local swelling in the bite area and 73 per cent had affected mental status. Initial cardiac auscultation examination was normal in all dogs, but six dogs had cardiac abnormalities at their second examination, including cardiac arrhythmias and cardiac murmurs. All dogs received fluid therapy, 36 dogs were given analgesics, 22 dogs were treated with glucocorticoids, and ten dogs were treated with antibiotics. Evidence of transient muscle damage (increased CK) was seen one day after the snake bite in 15 (54%) of 28 sampled dogs. Moderate changes in hepatic test results occurred in 1 dog and several dogs (22 of 34) had transient, minor increases in one or more hepatic test result. No dog died during the observation period as a consequence of the snake bite.

Conclusions

Snake bite caused local swelling in all dogs and mental depression of short duration in most dogs. Some dogs had transient clinical signs that could be indicative of cardiac injury and some other had transient biochemical signs of liver injury. Treatment with glucocorticoids did not have any clear positive or negative effect on clinical signs and mortality.     

Alveld-Producing Saponins: II. Toxicological Studies

The phototoxic lamb disease alveld, prevalent in South-Western Norway, is caused by ingestion of Narthecium ossifragum. Earlier studies have shown that peroral administration of large amounts of crude saponins from this plant elicits the disease. Such saponins have now been purified further by 2 different methods (A and B). Two A type preparations resulted in alveld when fed to 2 lambs. The most highly purified preparation (type B) did not cause alveld in the 2 lambs tested. Lambs vary, however, in their susceptibility to the disease. Both types of preparations led to increases in serum aspartate aminotransferase, bilirubin and 5′-nucleotidase in rats when injected intraperitoneally in amounts of 50 or 100 mg/kg body Weight. Cannulation of the bile duct showed that injected saponins reduced both the volume of bile and the amounts of bilirubin and bile acids excreted. Histological changes seen in the light microscope were, except for the most peripheral parts of the liver, hardly noticable. These observations support the view that saponins are the liver-toxic agents responsible for alveld. The possibility is discussed that the effect arises through a change in the lipid environment of carrier-mediated transport systems.     

Prevention of Milk Fever by Dietary Means: The Effect of a Concentrate Fortified with Mineral Salts

A concentrate was fortified with mineral salts by adding CaCl₂, Al₂(SO₄)₃ and MgSO₄ to standard concentrate A and pelleting the product When used as feed supplement from 3 weeks pre partum to 1 week post partum this concentrate mixture produced the intended negative alkali alkalinity in the total feed ration in 20 out of 25 cows. Of these 17 remained healthy in spite of a history of milk fever for the majority of them. Two cows got milk fever and 1 showed weak symptoms.