[Metastatic uveal melanoma. Development of neoadjuvant treatment in animal experiments]. / Metastasierendes uveales Melanom. Tierexperimentelle Entwicklung neoadjuvanter Therapien.

BACKGROUND: Up to 50% of patients with uveal melanoma develop metastases but none of the existing treatments of the primary tumor has been able to reduce the metastatic rate. Probably, micrometatases have already developed before treatment of the uveal melanoma and dormant micrometastases can persist for years before they start growing. This long time-span provides the possibility to treat micrometastases. METHODS: In order to develop an animal model for metastatic uveal melanoma, B16 melanoma cells were injected into the posterior ocular compartment of C57BL6 mice. These cells grew and metastasised to the lungs and liver. Immunological factors for the metastatic process and possible neoadjuvant treatments were investigated. RESULTS: Natural killer cells (NK) are of significance in the rejection of metastases and HLA-I expression of uveal melanomas correlates with the melanoma cell type. Interferon-alpha-2b increases the activity of NK cells and reduces the metastatic rate in the animal model. CONCLUSION: Treatment with interferon-alpha-2b results in decreased metastases from intraocular melanoma in a murine model.

Effects of cage versus floor rearing environments and cage floor mesh size on bone strength, fearfulness, and production of single comb White Leghorn hens.

Fourteen hundred pullets were reared at densities of 304 and 735 cm2 in cages and floor pens with litter, respectively. Feeder spaces of 2.7, 4.0, and 5.4 cm per bird were held constant during the brooding growing period. At 18 wk of age, the birds were housed four birds per cage (348 cm2 per bird) in a force-ventilated, light-controlled house with two rows of stair-step cages. In two rows, the standard 2.5 x 5.0 cm welded wire flooring was replaced randomly with 2.5 x 2.5 cm welded wire in eight-cage sections. Egg production, egg quality, feed conversion, and mortality were measured over a 48-wk production cycle. At 68 wk of age, a sample of hens was selected and euthanatized, and the right leg was excised for further evaluation. Rearing environment, rearing feeder space, or type of layer floor mesh had no significant effects on hen-day production or feed conversion. Hens reared in cages produced heavier (P < .001) eggs with a higher percentage of Grade A eggs and had fewer body checks than floor-reared birds. Femur, tibia, and shank lengths were not affected by the rearing treatments or the type of flooring in the layer cage. Tibia breaking strength was not different for the rearing systems or hens maintained on 2.5 x 2.5 vs 2.5 x 5.0 cm welded wire mesh flooring. Hens reared in floor pens on litter displayed a higher level of fearfulness at the end of the production cycle. The reduced (P < .05) body weights associated with cage rearing and reduced feeder space did not negatively affect the production variables. Alteration of the mesh size of layer cage floor had no effect on the production levels of the hens.

Effects of floor versus cage rearing and feeder space on growth, long bone development, and duration of tonic immobility in single comb White Leghorn pullets.

The effects of feeder space on growth of commercial layer pullets reared in cages or floor pens were examined by allocating 1-d-old chicks to either cages (14 chicks) or floor (119 chicks). Feeder spaces were 5.4, 4.0, and 2.7 cm per pullet and were held constant throughout the growing period, resulting in a 2 x 3 factorial arrangement. Measurements of pullet body weight, feed consumption, skeletal development, and fearfulness were taken through the rearing period to 18 wk. Pullets allowed 5.4 cm of feeder space were heavier (P < .001) (1,329 g at 18 wk of age) than birds allowed either 4.0 or 2.7 cm of feeder space (1,289 and 1,272 g, respectively). Floor-reared pullets weighed significantly more at 12, 16, and 18 wk of age than cage-reared pullets. Feed consumption was not affected by the feeder space, but the floor-reared birds consumed more (P < .001) feed than those in cages (61.2 vs 52.8 g per pullet per d). Mortality, skeletal development, and bone strength were not affected by either feeder space or floor vs cage rearing. Floor-reared pullets had longer (P < .05) duration of tonic immobility (TI) than those reared in cages (519.7 and 471.4 s, respectively, as measured at 18 wk). Feeder space per pullet had no effect on the duration of TI of the pullets. Cage and floor rearing environments are comparable for rearing pullets provided feeder space is not restricted to such an extent as to inhibit BW.

Effect of number of hens per nipple waterer on the performance of several strains of layers in cages.

Two experiments were designed to study the effects of housing in cages with several hens per nipple waterer (HPN) ratios on performance of several strains of White Leghorn pullets. In Experiment 1, only body weight gain and water consumption were significantly affected by the HPN; hens at the 2:1 HPN gained more weight and consumed more water per day than those at the 4:1 HPN. The lack of a significant strain by HPN interaction indicated that the four strains responded similarly to the different HPN ratios. In Experiment 2, hens in cages with 3.5:1 and 7:1 HPN consumed significantly more water and feed than those in cages with 10:1 and 14:1 HPN. In both experiments, the HPN had no significant effect on age at sexual maturity, egg production, mortality, and egg weight, but efficiency of feed usage for egg production decreased with the 3.5:1 and 7:1 HPN.

Effects of type of cage front and feed trough partitions on productivity and ingestive, agonistic, and fearful behaviors of egg-type hens.

Two groups of White Leghorn pullets reared in floor pens were used to study the effects on performance and behavior in cages of horizontal wire cage fronts with and without feed trough partitions (HP and H, respectively) and vertical wire cage fronts with and without feed trough partitions (VP and V, respectively). In Experiment 1, hens in HP and VP cages consumed more (P less than .05) feed than hens in either H or V cages. This greater feed consumption combined with similar egg production resulted in significantly poorer feed conversion (P less than .05) for hens in VP cages. Hens in HP cages had fewer drinking bouts (P less than .05) and an intermediate amount of feeding time. Hens in H, V, and VP cages did not differ significantly in number of drinking bouts and feeding times. There were differences in feeding location preferences among treatments (P less than .05) but not within treatments. In Experiment 2, effects of horizontal (H) and vertical (V) wire cage fronts were examined to determine their effects on productivity and fearful behavior. Hens in H cages had better feather scores (P less than .05) than hens in V cages. Type of cage front had no significant effects on age at sexual maturity, egg production, mortality rate, average egg weight, and body weight.

Effects of type of cage partition, cage shape, and bird density on productivity and well-being of layers.

In Experiment 1 there were no significant differences in rate of lay, egg quality, latency to feeding, and feather condition of hens in cages with wire mesh or solid metal side partitions. Birds in cages with solid metal side partitions had significantly higher mortality (6%) and weight gain (6%) than those in cages with wire side partitions. The deep caged hens had significantly lower mortality (8%) than the shallow caged hens. Hens housed at 464 cm2 of floor area/hen had significantly higher hen-housed egg production (4.9%), lower weight gain (8%), and higher average feather scores (.8 unit) than those housed at 348 cm2. In Experiment 2 type of cage side and back partitions (wire vs. solid metal) significantly affected grams of egg per gram of feed. Birds in deep cages had significantly lower mortality (8.6%) and higher feed consumption (15.2 g/hen/day) than those in shallow cages. Hen-housed rate of lay, mortality, weight gain, feed conversion, and feather scores were significantly affected by bird density: 64.6%, 15%, 24.6%, .384% g egg/g feed, and 4.7 units, respectively, for hens with 464 cm2 floor area vs. 70.8%, 8.3%, 25.2%, .362% g egg/g feed, and 5.8 units for hens with 348 cm2. Data suggest that hens in cages with solid metal sides performed similarly to their sisters in cages with wire mesh sides and backs.

Effects of declawing and cage shape on productivity, feathering, and fearfulness of egg-type chickens.

Declawing day-old egg-type chicks did not significantly (P less than .05) alter 20-week body weight. However, declawed hens tended to mature earlier and lay more eggs than the intact hens. Hens housed in shallow cages tended to be better feathered than those housed in deep cages. Neither declawing nor cage shape had a significant effect on the time required for birds to return to feeding after exposure to a noise stimulus, which was used as an indicator of fearfulness.

A feed additive to control flies in poultry manure.

To determine methoprene's effect on fly emergence from poultry manure, 18,000 8-wk.-old caged pullets were fed continuously 10 gm. of methoprene per ton of feed 42 days. Hatch mates (13,500) in an adjacent, similarly constructed and equipped house were fed untrated feed. Data on fly emergence were recorded twice a week after counting average numbers of flies in fly traps, in buckets of manure, and on fly strips and spot cards. Differences between average counts in the treated and control groups were significant by each of the four data-gathering methods. The methoprene reduced fly emergence by 77.0% in manure buckets, 65.5% in fly traps, but increased fly emergence 19.2% on fly strips, and 92.2% on spot cards. We attribute the increases in fly counts by the latter two counting methods in the treated house to migration of flies from adjacent untreated houses.

Some effects on layers of sodium sulfate and magnesium sulfate in their drinking water.

Potential for increasing contamination of water supplies with such materials as dissolved inorganic solids suggests more precise water quanlity standards for poultry. Commercial strain S.C.W.L. hens were supplied water containing sodium sulfate (Na2SO4) or magnesium sulfate (MgSO4) (250, 1,000, 4,000, or 16,000 p.p.m.) on a total sulfate basis in Exp. 1 and on a total salt basis in Exp. 2. All data are expressed as percentages deviated from pre-treatment performance. Four thousand p.p.m. of total sulfate as Na2SO4 or MgSO4 significantly depressed feed consumption and hen-day production. Magnesium sulfate (4,000 p.p.m.) had a more depressing effect than Na2SO4 (4,000 p.p.m.) on hen-day production (-80.4 vs. -24.4%). At that level, Na2SO4 significantly increased water consumption and fecal moisture content, while MgSO4 significantly decreased water consumption. All hens on 1l,000 p.p.m. of either salt died during the experiment. No effect on egg quality was observed before the hens died. On a total salt basis (Exp. 2) 16,000 p.p.m. of either Na2SO4 or MgSO4 significantly depressed hen-day production, body weight, and feed comsumption, but increased water consumption. Hens receiving 16,000 p.p.m. Na2SO4 increased water consumption more than those receiving 16,000 p.p.m. MgSO4(146.7 and 24.6%). No significant differences between treatments were observed for mortality (Exp. 2). Mortality data suggest that lethal levels of Na2SO4 and MgSO4 are between 16,000 and 20,032 or 23,680 p.p.m. total salt, respectively.

The influence of dietary nitrate on nitrate concentration in egg yolk and albumen.

Sodium nitrate (from 0 to 2,000 p.p.m.) was added to the drinking water of 32-week old S.C. White Leghorn pullets. Eggs collected once a week for 8 weeks were analyzed for nitrate content. Increasing levels of nitrate in the drinking water resulted in increasing levels of nitrate in albumen and yolk. Higher levels of nitrate were found in the yolk than in the albumen. When birds were started on the experiment, nitrate in the drinking water was reflected by immediate increases in nitrate content of the eggs. The nitrate content of eggs from birds receiving 1,000 p.p.m. NaNO3 (728 p.p.m. NO3-) exceeded the 45 p.p.m. permissible level of nitrate in drinking water for human beings.