Male broilers of two genetically related stocks with divergent growth rates and feed conversion ratios were used to study metabolic backgrounds on the occurrence of pulmonary hypertension, heart failure, hypoxemia, and ascites in poultry. An experiment with a 2 x 2 x 2 x 2 factorial split-plot arrangement of treatments with 96 groups of 12 broilers was performed. Effects of stock and environmental factors such as ambient temperature, dietary fat, and dietary energy on performance, energy metabolism, oxygen consumption, hematocrit values, and mortality were investigated in broilers from 1 to 5 wk of age. Dissimilar responses of the two stocks to environmental factors reflected genotype by environment interactions and revealed metabolic disorders related to heart failure and ascites. The results indicated that in the stock with the lower feed conversion ratio, a fast protein accretion was achieved together with a reduced ability to convert chemical energy to metabolic heat and to deposit body fat directly from ingested fat. Birds with a low feed conversion ratio show less flexibility in metabolic adaptation to a changing environment, which can account for the development of ascites.

We have identified a novel lentivirus prevalent in talapoin monkeys (Myopithecus talapoin), extending previous observations of human immunodeficiency virus-1 cross-reactive antibodies in the serum of these monkeys. We obtained a virus isolate from one of three seropositive monkeys initially available to us. The virus was tentatively named simian immunodeficiency virus from talapoin monkeys (SIVtal). Despite the difficulty of isolating this virus, it was readily passed between monkeys in captivity through unknown routes of transmission. The virus could be propagated for short terms in peripheral blood mononuclear cells of talapoin monkeys but not in human peripheral blood mononuclear cells or human T cell lines. The propagated virus was used to infect a naive talapoin monkey, four rhesus macaques (M. mulatta), and two cynomolgus macaques (M. fascicularis). All animals seroconverted and virus could be reisolated during a short period after experimental infection. A survey of SIVtal-infected captive talapoin monkeys revealed a relative decrease in CD4(+) cell numbers in chronically (>2 years) infected animals. No other signs of immunodeficiency were observed in any of the infected animals. PCR amplification followed by DNA sequencing of two fragments of the polymerase gene revealed that SIVtal is different from the presently known lentiviruses and perhaps most related to the SIV from Sykes monkeys.

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In order to study kinetics of the spermatogenic epithelium in the adult boar, a method has been developed to prepare seminiferous tubules mounted as a whole, after which these tubules have been processed and studied as described previously only for rats, mice and hamsters. The tubules were fixed in Zenker for 24 hours and stained with periodic acid - Schiff - haematoxylin to identify the steps in spermatid development, or by Harris' hemalum to identify spermatogonia and spermatogonial divisions. Spermatid development in the boar is comparable with spermatid development in small laboratory rodents. The spermatogenic cycle was divided into 12 steps, each characterized by one step in the development of the acrosome or the shape of the nucleus of the spermatids. By studying whole mounts we could distinguish four classes of spermatogonia in the boar: undifferentiated A spermatogonia (A s, A pr, A al), differentiating A spermatogonia (A1, A2, A3, A4), intermediate and B spermatogonia. The boar demonstrates a striking similarity with small laboratory rodents.

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