Nest use is influenced by the positions of nests and drinkers in aviaries

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nest

Engineering geological models: an introduction: IAEG commission 25

The generation and use of engineering geological models should be a fundamental activity for any geotechnical project. Such models are an essential tool for engineering quality control and provide a transparent way of identifying project-specific critical engineering geological issues and parameters. Models should also form the basis for designing the scope, the method and assessing the effectiveness of site investigations. However, whilst the idea of models in engineering geology has existed for several decades, there has been little published that systematically distinguishes the different model types and how and when they might be used. This paper presents the views of the International Association for Engineering Geology and the Environment Commission C25 on the ‘Use of Engineering Geological Models

Nest use is influenced by the positions of nests and drinkers in aviaries.

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nests

H/L ratio as a measurement of stress in laying hens - methodology and reliability.

Measuring the ratio of heterophils and lymphocytes (H/L) in response to different stressors is a standard tool for assessing long-term stress in laying hens but detailed information on the reliability of measurements, measurement techniques and methods, and absolute cell counts is often lacking. Laying hens offered different sites of the nest boxes at different ages were compared in a two-treatment crossover experiment to provide detailed information on the procedure for measuring and the difficulties in the interpretation of H/L ratios in commercial conditions. H/L ratios were pen-specific and depended on the age and aviary system. There was no effect for the position of the nest. Heterophiles and lymphocytes were not correlated within individuals. Absolute cell counts differed in the number of heterophiles and lymphocytes and H/L ratios, whereas absolute leucocyte counts between individuals were similar. The reliability of the method using relative cell counts was good, yielding a correlation coefficient between double counts of r > 0.9. It was concluded that population-based reference values may not be sensitive enough to detect individual stress reactions and that the H/L ratio as an indicator of stress under commercial conditions may not be useful because of confounding factors and that other, non-invasive, measurements should be adopted

Unexpected complexity of Wnt gene family in a sea anemone

The Wnt gene family encodes secreted signalling molecules that control cell fate in animal development and human diseases. Despite its significance, the evolution of this metazoan-specific protein family is unclear. In vertebrates, twelve Wnt subfamilies were defined, of which only six have counterparts in Ecdysozoa (for example, Drosophila and Caenorhabditis). Here, we report the isolation of twelve Wnt genes from the sea anemone Nematostella vectensis, a species representing the basal group within cnidarians. Cnidarians are diploblastic animals and the sister-group to bilaterian metazoans. Phylogenetic analyses of N. vectensis Wnt genes reveal a thus far unpredicted ancestral diversity within the Wnt family. Cnidarians and bilaterians have at least eleven of the twelve known Wnt gene subfamilies in common; five subfamilies appear to be lost in the protostome lineage. Expression patterns of Wnt genes during N. vectensis embryogenesis indicate distinct roles of Wnts in gastrulation, resulting in serial overlapping expression domains along the primary axis of the planula larva. This unexpectedly complex inventory of Wnt family signalling factors evolved in early multi-cellular animals about 650 million years (Myr) ago, predating the Cambrian explosion by at least 100 Myr (refs 5, 8). It emphasizes the crucial function of Wnt genes in the diversification of eumetazoan body plans

Preliminary U-series and Thermo luminescence dating of excavated deposits in Liang Bua sub-chamber, Flores, Indonesia

We report the results of a test excavation of deposits in a limestone cave sub-chamber located beneath the main chamber of Liang Bua, Flores, Indonesia: the discovery site of the small hominin species, Homo floresiensis. Well-preserved remains of extinct Pleistocene fauna and stone artefacts have previously been identified on the surface of a sediment cone within the sub-chamber. Our excavation of the deposits, at the base of the sediment cone in the sub-chamber (to 130 cm depth) yielded only a few fragmentary bones of extant fauna. Uranium/Thorium (U-series or U/Th) dating of soda straw stalactites excavated from 20 to 130 cm in depth demonstrates that the excavated sediments were deposited during the Holocene. Red Thermoluminescence (TL) dating of the sediments at the base of the excavation (130 cm depth) indicates these sediments were last exposed to sunlight at 84 +/- 15 ka (thousand years), similar to red TL. ages of cave sediments from the main chamber. Together, these results indicate that the surface faunal remains, which are morphologically analogous to Pleistocene finds from the main chamber excavations, were transported to the sub-chamber relatively recently from the main chamber of Liang Bua and probably originated from conglomerate deposits at the rear of the cave and from deposits around the front entrance. There is no evidence for hominin occupation of the sub-chamber, instead it seems to have acted as a sink for cultural materials and fossil remains transported from the surface via sinkholes. Despite the small number of finds from the test excavation, it is possible that more extensive excavations may yield additional transported cultural and faunal evidence at greater depths. (C) 2012 Elsevier Ltd. All rights reserved