Effect of environmental enrichment at two stages of development on belly nosing in piglets weaned at fourteen days1

2006 ◽  
Vol 84 (12) ◽  
pp. 3397-3403 ◽  
Author(s):  
C. J. Bench ◽  
H. W. Gonyou
1963 ◽  
Vol 22 (4) ◽  
pp. 1093-1096 ◽  
Author(s):  
D. E. Becker ◽  
I. D. Smith ◽  
S. W. Terrill ◽  
A. H. Jensen ◽  
H. W. Norton

2002 ◽  
Vol 25 (12) ◽  
pp. 1639-1649 ◽  
Author(s):  
P. BALDET ◽  
C. DEVAUX ◽  
C. CHEVALIER ◽  
R. BROUQUISSE ◽  
D. JUST ◽  
...  

This paper is divided into three parts: the first relating to the blood-corpuscles of the Vertebrata ; the second to those of the In-vertebrata ; and the last to a comparison between the two. He first describes the microscopic appearances of these corpuscles in differ­ent classes of vertebrate animals, beginning with the skate and the frog, and proceeding to birds and mammifera; first in their early embryonic state, and next in the subsequent periods of their growth. He finds in oviparous vertebrata generally, four principal forms of corpuscles. These he distinguishes as the phases, first of the gra­nule blood-cell , which he describes as a cell filled with granules, dis­closing by the solvent action of dilute acetic acid on these granules a vesicular, or as the author terms it, a “ cellœform ” nucleus. These granule cells appear under two stages of development, namely, the coarsely granulous stage and the finely granulous stage. The se­cond phase is that of the nucleolated blood-cell , oval in shape, con­taining a vesicular (or “cellæform”) nucleus, and red-coloured mat­ter. These cells likewise appear under two stages of development; colourless in the first and coloured in the second, in which last stage it constitutes the red corpuscle. In the early mammiferous embryo, he finds, in addition to the former, a third phase, that of free vesicu­lar nucleus , exhibiting, like the nucleolated cell, the colourless and the coloured stages. On examining the corpuscles of the lymph of vertebrate animals, the author finds them in all the classes to be identical in structure with their blood-corpuscles, and differing only in the inferior degree of coloration attending their last stage. In the oviparous classes, he observes that the nucleolated are more numerous than the granule cells, while in the mammifera the latter are predominant, which is the reverse of the proportion in which they exist in the blood of these animals. He finds that some of the nucleolated cells of the contents of the thoracic duct exhibit a marked degree of coloration, and have an oval shape; thus offering a resemblance to the blood of the early embryonic state.


1960 ◽  
Vol 38 (3) ◽  
pp. 353-363 ◽  
Author(s):  
J. E. Andrews

Young winter rye seedlings, grown and hardened at 1° or 1.5 °C in the dark, developed a high level of cold hardiness at two stages prior to emergence of the first leaf. The first maximum occurred when coleoptiles were less than about 1 mm in length and was followed by a decrease in hardiness. A second and higher maximum occurred when coleoptiles were about 15–30 mm in length (5 weeks at 1.5 °C; 7 weeks at 1 °C) and it was followed by a rapid decrease in hardiness beginning at about the time the leaf broke through the coleoptile. Genetic differences corresponding with those obtained in the field were established by hardening seedlings for 7 weeks at 1 °C and exposure to −15 °C for 16 hours or by hardening for 5 weeks at 1.5 °C and exposure to −14 °C for 16 hours. The use of a lower (−4 °C) hardening temperature resulted in a large increase in cold hardiness at the younger stages of development but little or no increase where seedlings had already reached a maximum of hardiness from exposure to 1.5 °C for 5 weeks. Satisfactory genetic differences were not determined by exposure to −14 °C for 16 hours after hardening at −4 °C. In general the response to hardening of young winter rye seedlings was similar to that found with winter wheat.


1931 ◽  
Vol 25 (3-4) ◽  
pp. 129-143 ◽  
Author(s):  
H. T. Wade-Gery

In an earlier paper on this topic, ‘Eupatridai, Archons, and Areopagus,'3 I was primarily concerned to recover the views of Aristotle, as expressed in the ‘Αθ. πολ., on such elements of Attic Society as Eupatridai, Gennetai, etc. I sought to establish that to him at least these two were not identical: that, more precisely, he recorded two stages of development—(a) ‘Ion’: in whose day the whole body of Athenians was composed of Gennetai, while Eupatridai had not yet been created.(b) ‘Theseus’: who created the Eupatridai—distinguishing them, as a Third Estate, from those two Estates (Georgoi and Demiourgoi) which had hitherto, since Ion, composed the body of Athenians.


1955 ◽  
Vol 102 (4) ◽  
pp. 393-402 ◽  
Author(s):  
W. Wilbur Ackermann ◽  
Hunein F. Maassab

A further analysis of the growth curve obtained in vitro for influenza virus in chorioallantoic membrane has been made using the viral inhibitor p-fluorophenylalanine. It has been found that p-fluorophenylalanine is phase-specific, does not interfere with the initiation of infection but rather acts during the productive period of the infectious sequence. The site of action of this fluoroderivative has been described relative to the site of action of methoxinine. By the use of this inhibitor in combination with methoxinine, it has been possible to recognize two stages of development which were not discernible from the usual growth curve. In a multicellular culture these two reactions, A and B, occur for the most part simultaneously, during the latent and productive periods. Reaction A is inhibited by methoxinine, but not by fluorophenylalanine. It begins early in the latent period and can proceed independent of reaction B. Reaction B is inhibited by fluorophenylalanine, but not by methoxinine, and it cannot proceed unless reaction A is proceeding or has operated for some prior interval.


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