Non-experimental Animals Research Articles

Characterization of Species Differences in Xenobiotic Metabolism in Non-experimental Animals

The ability to metabolize xenobiotics in organisms has a wide degree of variation among organisms. This is caused by differences in the pattern of xenobiotic bioaccumulation among organisms, which affects their tolerance. It has been reported in the veterinary field that glucuronidation (UGT) activity in cats, acetylation activity in dogs and sulfation (SULT) activity in pigs are sub-vital in these species, respectively, and require close attention when prescribing the medicine. On the other hand, information about species differences in xenobiotics metabolism remains insufficient, especially in non-experimental animals. In the present study, we tried to elucidate xenobiotic metabolism ability, especially in phase II UGT conjugation of various non-experimental animals, by using newly constructed in vivo, in vitro and genomic techniques. The results indicated that marine mammals (Steller sea lion, northern fur seal, and Caspian seal) showed UGT activity as low as that in cats, which was significantly lower than in rats and dogs. Furthermore, UGT1A6 pseudogenes were found in the Steller sea lion and Northern fur seal; all Otariidae species are thought to have the UGT1A6 pseudogene as well. Environmental pollutants and drugs conjugated by UGT are increasing dramatically in the modern world, and their dispersal into the environment can be of great consequence to Carnivora species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.

Ecological Trade-offs between Migration and Reproduction Are Mediated by the Nutrition-Sensitive Insulin-Signaling Pathway.

Crowding and changes in food availability are two critical environmental conditions that impact an animal's trajectory toward either migration or reproduction. Many insects facing this challenge have evolved wing polyphenisms. When conditions favor reproduction, wing polyphenic species produce adults that either have no wings or short, non-functional wings. Facultative wing growth reflects a physiological and evolutionary trade-off between migration and reproduction, triggered by environmental conditions. How environmental cues are transduced to produce these alternative forms, and their associated ecological shift from migration to reproduction, remains an important unsolved problem in evolutionary ecology. The brown planthopper, a wing polymorphic insect exhibiting strong trade-offs in investment between migration and reproduction, is one of the most serious rice pests in Asia. In this study, we investigated the function of four genes in the insulin-signaling pathway known to couple nutrition with growth, PI3 Kinase (PI3K), PDK1, Akt (Protein Kinase B), and the forkhead gene FOXO. Using a combination of RNA interference and pharmacological inhibitor treatment, we show that all four genes contribute to tissue level regulation of wing polymorphic development in this insect. As predicted, silencing of the NlPI3K, NlAkt and NlPDK1 through dsRNA and with the pharmacological inhibitor Perifosine resulted in short-winged brown planthoppers, whereas knockdown of NlFOXO resulted in long-winged planthoppers. Morphometric analyses confirm that phenotypes from our manipulations mimic what would be found in nature, i.e., major parameters such as bristle number, wing area and body weight are not significantly different from non-experimental animals. Taken together, these data implicate the insulin-signaling pathway in the transduction of environmental factors into condition-dependent patterns of wing growth in insects.

Providing elevated ‘getaway bunks’ to nursing mink dams improves their health and welfare

Farmed mink infants (Neovison vison) remain with their mothers beyond natural weaning age. This benefits their welfare, but can stress their mothers and contribute to illness (e.g. ‘nursing sickness’). European studies have explored augmenting cages with structures allowing mothers to get away from their infants (‘kits’); these show that if provided with high, shelf-like structures permitting rest away from kits, dams utilise them. Here, we assessed the benefits of providing an elevated ‘getaway bunk’ – a wire-mesh half-cylinder attached to the cage ceiling – to 80 Black dams on an Ontario farm. Controls comprised nursing females without bunks (n=80), and barren females given bunks (n=40). Behaviour was observed daily over kit ages 23–42 days. Mothers were removed from litters at 42 days (typical for North American farms), at which time health and production parameters were recorded. Mothers used bunks approximately half as much as barren dams, but their bunk-use increased as kits aged, up to c. 7% scans (c. 30min per observation day). Seasonal changes in temperature did not explain this pattern. Bunks increased maternal rest (from 78.9 to 82.3% of scans; c. 16min per observation day), and increased the time spent with teats inaccessible to kits by a similar amount. Dams with bunks showed approximately one third less stereotypy (3.7% scans, compared to 5.4% in bunkless controls): a reduction most evident when kits were aged 30–42 days, when infants transition from milk to water and solid food; and, although apparently not protected from nursing sickness, at the end of lactation they were less likely to have swollen, red and/or crusty teats (which thermal imaging also showed were significantly hotter), suggesting less mastitis. Such benefits seemed particularly strong in multiparous dams: effects of bunks on teat health and stereotypy as a proportion of activity (not scans) were significant in older dams but not first-time mothers when analysed separately. Kits’ suckling opportunities and time spent nursing were not significantly reduced by the bunks, however; nor did bunks compromise kit survivorship or weights at 42 days. Elevated bunks can thus enhance mink mothers’ welfare during the nursing period, seemingly without serious drawbacks for their kits. Unexpectedly, however, all study dams had very high mortality (>20%; more than triple that of non-experimental animals on the farm), suggesting that repeated live observation, or being housed close to barren dams, may elevate risks of nursing sickness.

Intervertebral disc cell- and hydrogel-supported and spontaneous intervertebral disc repair in nucleotomized sheep

PurposeRegenerative repair is a promising new approach in treating damaged intervertebral discs. An experimental scheme was established for autologous and/or allogenic repair after massive disc injury.MethodsDisc healing was promoted in 11 animals by injecting in vitro expanded autologous/homologous disc cells 2 weeks after stab injury of lumbar discs L1-2. The following control discs were used in our sheep injury model: L2-3, vehicle only; L3-4, injury only; L4-5, undamaged; and lumbar discs from four non-experimental animals. Disc cells were suspended in a biologically supportive albumin/hyaluronan two-component hydrogel solution that polymerizes when inserted in order to anchor cells at the injection site. The parameters studied were MRI, DNA, glycosaminoglycan, collagen content, histology, immunohistology for collagens type I, II and aggrecan, and mRNA expression of GAPDH, β-actin, collagen type I, II, X, aggrecan, lubricin, and IL-1β.ResultsAll parameters demonstrated almost complete healing of the injured discs after 6 months, when compared with data from both the endogenous non-injured controls as well as from the healthy animals.ConclusionSheep experience spontaneous recovery from disc injury. The process of endogenous repair can be enhanced by means of hydrogel-supported cells.

The welfare of gestating sows in conventional stalls and large groups on deep litter

Confinement of breeding sows and gilts is a controversial welfare issue in livestock production and there is worldwide interest in finding alternative housing systems for gestating pigs. This study measured aspects of the welfare of gestating sows housed in either large groups on deep litter (Hoops) or conventional stalls (Stalls). Six hundred and forty sows were studied, with 40 recently mated sows weekly entering each treatment over an 8-week period; groups of 85 were formed using 40 experimental and 45 non-experimental animals. Sows in Hoops had a higher ( P < 0.001) number of scratches, a higher ( P < 0.01) return rate to oestrus after mating (13.20% versus 7.35%) and there was a trend ( P = 0.06) for higher salivary cortisol concentrations in week 1 of gestation (6.29 nM versus 4.03 nM). Sows in Stalls had a higher incidence of lameness at weeks 9 and 15 of gestation (13.8% versus 0.8% at week 15) ( P < 0.01). There were changes in some leucocyte sub-populations in the Stalls treatment late in gestation: the percentage of neutrophils was higher (46% versus 41% of WBC), the number and percentage of lymphocytes was lower (4.59 × 10 6 c/mL versus 5.16 × 10 6 c/mL and 41.6% versus 46.5% of WBC) and consequently there was a higher neutrophil:lymphocyte ratio (1.22 versus 0.94) ( P < 0.05). There was a trend ( P = 0.06) for a lower reproductive failure in the Stalls treatment (14.5% versus 27.3%); farrowing rate was higher (76.8% versus 66%), and while sows in Stalls weaned fewer piglets per litter (8.31 versus 8.97), the average weaning weight of these piglets was higher (8.69 kg versus 8.01 kg) ( P < 0.01). The combination of these reproductive parameters resulted in sows in the Stall treatment weaning the equivalent of 39 more piglets per 100 mated sows. The results suggest that sows in large groups on deep litter faced greater welfare challenges in the early stages of gestation based on the findings of increased scratches, a higher rate of return to oestrous and a trend for higher cortisol concentrations early in gestation, all possibly a consequence of aggression. In contrast sows in stalls faced greater welfare challenges later in gestation based on a higher incidence of lameness and an increased neutrophil:lymphocyte ratio perhaps as a consequence of increased stress. In conclusion, these data suggest that in both housing systems the welfare advantages and disadvantages change overtime.

Pax-6 Expression in Posthatch Chick Retina during and Recovery from Form-Deprivation Myopia

The expression of Pax-6 in fully-differentiated chick retina remains largely confined to the amacrine and ganglion cell layers. In the developing posthatch chick retina, Pax-6 expression shows a biphasic pattern; a decrease by posthatch day 17 followed by a steady increase in the adult eye. Interestingly, we find that this biphasic expression of Pax-6 is reflected in the biphasic growth pattern of the posthatch chick eye, which is disrupted by form-deprivation myopia (FDM). We have now examined the pattern of Pax-6 accumulation in 3-day-old chick eyes subjected to 2 weeks of FDM followed by 2 weeks of recovery from FDM. Quantitative RT-PCR (with a homologous internal control) revealed that after 2 weeks of occlusion the contralateral non occluded eyes, the occluded eyes and the normal nonexperimental chick eyes did not show any drastic changes in the number of Pax-6 transcripts. The data obtained suggests that the contralateral eye does not represent a ‘normal’ control eye; similar but nonidentical changes are seen, at the molecular level, in both the contralateral and the occluded eyes. Comparisons with the control nonexperimental animals, however, are meaningful. Even after 2 weeks of recovery under normal light conditions, the occluded eyes do not seem to reach the same level of Pax-6 expression (number of molecules per mg tissue) as seen in normal control eyes, suggesting that exposure of the posthatch chick eye to FDM impedes developmental progression that normally culminates in emmetropia.

The effect of continuous or rotational stocking on the intake and live-weight gain of cattle co-grazing with sheep on temperate pastures

AbstractTwo experiments were conducted to determine if type of stocking system influenced the intake and live-weight gain (LWG) of cattle co-grazed with sheep on sown ryegrass/white clover pasture.In experiment 1 (134 days), yearling heifers (no. = 9) plus ewe hoggets (no. = 27) were co-grazed (1: 1 M0·75) using continuous (C-CS) or rotational (R-CS) stocking. In experiment 2 (126 days), a cattle alone (no. = 9) treatment was included under each stocking system (C-C and R-C). Initial live weight of heifers was 266 (s.e. 4·5) and 232 (s.e. 4·4) kg and that of hoggets was 54 (s.e. 0·9) and 47 (s.e. 0·7) kg in experiments 1 and 2, respectively. In both experiments, the area offered daily to R-CS group was manipulated to promote a weekly live-weight change in sheep similar to that on the C-CS treatment. C-C cattle in experiment 2 were grazed at similar sward surface height (SSH) to C-CS, and R-C cattle at similar pre- and post-grazing SSH to R-CS. SSH was measured daily on all treatments and regulated on the continuously stocked treatments by addition and removal of non-experimental animals. Organic matter intake (OMI) was determined from the ratio of n-alkanes in faeces and herbage. Animals were weighed weekly.Mean SSH on continuously stocked pastures was 5·10 (s.e. 0·03) and 4·26 (s.e. 0·02) cm for C-CS in experiments 1 and 2, respectively, and 4·27 (s.e. 0·02) cm for C-C in experiment 2. The mean pre- and post-grazing SSH for R-CS was 15·9 (s.e. 0·12) and 5·60 (s.e. 0·07) cm, respectively in experiment 1, and 15·2 (s.e. 0·08) and 4·82 (s.e. 0·03) cm, respectively in experiment 2. On R-C swards pre- and post-grazing SSH was 14·9 (s.e. 0·08) and 4·87 (s.e. 0·03) cm, respectively.In experiment 1, cattle continuously co-grazed with sheep grew significantly more slowly than those rotationally co-grazed with sheep (804 (s.e. 41·6) v. 1039 (s.e. 47·7) g/day, P &lt; 0·01). Sheep LWG did not differ between stocking treatments (150 v. 138 g, P &gt; 0·05 for C-CS and R-CS respectively). These findings were confirmed in the second experiment in which C-CS cattle only grew at 0·69 of the daily LWG achieved by R-CS cattle (706 v. 1028, (s.e. 72) g/day; P &lt; 0·05) at similar sheep LWG (155 v. 147, (s.e. 6·5) g/day respectively). LWG of C-C and R-C cattle was similar (916 v. 1022, (s.e. 72) g/day; P &gt; 0·05). LWG per ha in both experiments was higher on R-CS than on C-CS treatments, and on cattle alone than on CS treatments. Treatment effects on OMI and final fasted live weight were similar in pattern to LWG.It is suggested that the observed disadvantage to cattle when co-grazed with sheep under continuous stocking and the lack of effect when rotationally co-grazed reflected a difference in the two stocking systems in providing opportunities for complementary/competitive use of pasture resources.

Responses of cattle to different space allowances, pen sizes and road conditions during transport

Angus x Shorthorn heifers weighing about 350 kg were used to study the responses of heart rate and behaviour to different pen sizes, space allowances and road conditions during transport. In experiment 1, 6 groups of 9 heifers were transported at contrasting space allowances (0.9 and 1.1 m2/animal) on two 135- km journeys over a predetermined route of country, highway and suburban roads. Space allowance was varied by adjusting pen size. In experiment 2,4 groups of 8 heifers were used in a 2 (space allowances [0.8 and 1.0 m2/animal])x2 (pen sizes [8 and 16 m2]) factorial experiment to determine animal responses during a 31 km journey over sealed suburban roads. Space allowance was adjusted by adding non-experimental animals from the same herd. In experiment 3,6 groups of 7 animals were used to study the response of cattle to 2 space allowances (0.89 and 1.14 mVanima1) during a journey of 424 km. Space allowance was adjusted by using non-experimental animals from the same herd. In all experiments, animals transported at the lower space allowances had 3.9-6.7% lower heart rates (P &lt; 0.05) and l27-260% lower movement scores (P &lt; 0.05) than did animals transported at higher space allowances. In experiment 1, road type significantly affected heart rate (P&lt;0.05) but not movement. In experiment 2, both heart rate and movement were significantly (P&lt;0.01) less in small pens compared with large pens (heart rate 68.8 v. 71.7 bpm; number of movements 7.1 v. 15.8). There was a significant (P&lt;0.05) interaction between space allowance and pen size on heart rate, but not on the amount of movement. In experiment 3, the stage of the journey did not affect the difference in heart rate between space allowance treatments. It is concluded that, within the ranges of the variables examined, road transport was less demanding on cattle in small pens with a small space allowance. It is suggested that space allowances can be more readily manipulated in transport vehicles with small pens and so minimise risks to animal welfare during rapid changes in vehicle motion.

Mesotheliomatous tumors in South Africa: pathology and experimental pathology.

Annals of the New York Academy of SciencesVolume 132, Issue 1 p. 623-646 Free Access MESOTHELIOMATOUS TUMORS IN SOUTH AFRICA: PATHOLOGY AND EXPERIMENTAL PATHOLOGY Ian Webster, Ian Webster Pneumoconiosis Research Unit, Council for Scientific and Industrial Research Asbestosis Research Project, Johannesburg, South Africa*Search for more papers by this author Ian Webster, Ian Webster Pneumoconiosis Research Unit, Council for Scientific and Industrial Research Asbestosis Research Project, Johannesburg, South Africa*Search for more papers by this author First published: December 1965 https://doi.org/10.1111/j.1749-6632.1965.tb41142.xCitations: 19 Sponsored by the State Department of Mines and the Asbestos Mining Industry of South Africa. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat References 1 Wagner, J. C. 1960. Some pathological aspects of asbestosis in the Union of South Africa. In Proceedings of the Pneumoconiosis Conference. Johannesburg, 1959. A. J. Orenstein, Ed. J. & A. Churchill, Ltd. London , England . 2 Wagner, J. C., C. A. Sleggs & Paul Marchand. 1960. Diffuse pleural mesothelioma and asbestos exposure in the North Western Cape Province. Brit. J. Ind. Med. 17: 260. 3 Wagner, J. C. 1962. The Pathology of Asbestosis in South Africa. Thesis presented for the degree of Doctor of Medicine, University of the Witwatersrand. Republic of South Africa . 4 Stout, A. P. & M. R. Murray. 1942. Localized pleural mesothelionia: investigation of its characteristics and histogenesis by method of tissue culture. Arch. Path. 34: 951. 5 Clagett, O. T., J. R. McDonald & H. W. Schmidt. 1952. Localized fibrous mesothelioma of the pleura. J. Thorac. Cardiovasc. Surg. 24: 213. 6 Price-Thomas, C. & C. E. Drew. 1953. Fibroma of the visceral pleura. Thorax 8: 180. 7 McCaughey, W. T. E. 1958. Primary tumours of the pleura. J. Path. Bacteriol. 76: 517. 8 Winslow, D. J. & H. B. Taylor. 1960. Malignant peritoneal mesotheliomas. Cancer 13: 127. 9 Meyer, K. & E. Chaffee. 1939. Hyaluronic acid in pleural fluid associated with malignant tumor involving pleura and peritoneum. Proc. Soc. Exptl. Biol. Med. 42: 797. 10 Wagner, J. C., D. E. Munday & J. S. Harington. 1962. Histochemical demonstration of hyaluronic acid in pleural mesotheliomas. J. Path. Bact. 84: 73. 11 Harington, J. S., J. C. Wagner & Marianne Smith. 1963. The detection of hyaluronic acid in pleural fluids of cases with diffuse pleural mesotheliomas. Brit. J. Exp. Path. 44: 81. 12 Sleggs, C. A. Personal communication. 13 Republic of South Africa. 1962. Pneumoconiosis Compensation Act, No. 64. 14 Marchand, Paul. Personal communication. 15 Oettlé, A. G. 1965. Cancer in Africa, especially in regions south of the Sahara. J. Nat. Cancer. Inst. (in press). 16 Thomson, J. G., O. C. Kaschula & R. R. MacDonald. 1963. Asbestos as a modern urban hazard. South African Med. J. 37: 77. 17 Chatgidakis, C. B. & I. Webster. To be published. 18 Oettlé, A. G. Personal communication. 19 Webster, I. 1963. Asbestosis in non-experimental animals in South Africa. Nature 197: 506. Citing Literature Volume132, Issue1Biological Effects of AsbestosDecember 1965Pages 623-646 ReferencesRelatedInformation

Asbestosis in non-experimental animals in South Africa.

ASBESTOSIS has been produced in monkeys, rabbits and guinea pigs exposed to crocidolite, amosite and chrysotile asbestos dusts in experimental dust rooms1. No record of asbestosis occurring in non-experimental animals has been found, although Kiviluoto found anthophyllite asbestos fibres in the lungs of a cow from the vicinity of an asbestos mine2. He suggested that this finding supported his contention that the mining process was not directly responsible for the inhalation of asbestos dust in those cases of bilateral pleural calcification in which there was no history of an industrial exposure to asbestos dust.

Cytochemical and cytological studies of the parietal eye of the lizard, Sceloporus occidentalis

1. Illuminated and dark-adapted parietal eyes of 44 Western Fence Lizards, Sceloporus occidentalis, were studied cytochemically. Additionally, the eyes of 46 non-experimental animals were variously fixed and stained, many of them with 1% osmium tetroxide for electron microscopy. 2. Glycogen, demonstrated by the periodic acid Schiff (PAS) reaction, was more abundant in dark-adapted eyes and occurred particularly in the basal (luminal) half of the lens, the humor of the eye, “paraboloid” and perinuclear regions of photoreceptors, and “vesicles” in the nervous layer. Illuminated eyes showed a decrease in PAS-positive material, especially in lens and lumen. It is concluded that the lens secretes glycogen and perhaps other polysaccharides into the cavity of the eye and that possibly these substances may be used by the photoreceptoral processes. 3. Oil red O and oil blue N revealed pyridine-soluble lipids in the chromatophores of the capsule of the eye. These chromatophores appear to have characteristics of both lipophores and guanophores. 4. Staining with methyl green-pyronin showed desoxyribonucleic acid in nuclei and ribonucleic acid (RNA) in the following: basal (luminal) part of lens cytoplasm, the luminal humor, “paraboloid” and perinuclear regions of photoreceptors, and perikarya of ganglion cells. The RNA in ganglion cells is identified with Nissl substance. There was no apparent difference in RNA content of light and dark-adapted eyes. 5. Metachromasia to azure B and toluidine blue was observed in the RNA-positive regions of lens, lumen, and retina. 6. Osmium tetroxide was bound especially by the basal (luminal) ends of lens cells and by some of the cytoplasmic granules in capsular chromatophores. 7. Melanin pigment in the retinal melanocytes was observed to shift lumenward in a 48-hour illumination of the eye and to retreat basally during darkadaptation. 8. It is suggested that the luminal melanin-bearing cells may be macrophages.