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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 15.

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Niche Evolution, Trophic Structure, and Species Turnover in Model Food WebsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 56-67, July 2009. Abstract: The features that govern the stability and persistence of species interaction networks, such as food webs, remain elusive, but recent work suggests that the distribution and strength of trophic links play an important role. Potential omnivory‐stability relationships have been investigated and debated extensively, but we still have a relatively poor understanding of how levels of omnivory relate to the stability of diverse food webs. Here, we use an evolutionary assembly model to investigate how different trade‐offs in resource use infl...
Source: The American Naturalist - May 21, 2009 Category: Zoology Tags: article Source Type: journals

Association of the amino acid motifs of BoLA-DRB3 alleles with mastitis pathogens in Japanese Holstein cowsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The association of the polymorphism of bovine leukocyte antigen (BoLA-DRB3) genes, identified by the polymerase chain reaction sequence-based typing (PCR-SBT) method, with resistance and susceptibility to mastitis caused by Streptococci, coagulase-negative Staphylococci, Escherichia coli and Staphylococcus aureus was investigated. Blood samples for DNA extraction were collected from 170 Holstein cows (129 mastitis and 41 healthy cows) from 5 districts in Chiba prefecture, Japan. Susceptibility or resistance to the mastitis-causing pathogens was thought to vary by the presence of amino acid substitutions at the 9, 11, 13, a...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Tatsuyuki YOSHIDA, Harutaka MUKOYAMA, Hiroki FURUTA, Yasuko KONDO, Shin-nosuke TAKESHIMA, Yoko AIDA, Motoaki KOSUGIYAMA, Hiroshi TOMOGANE Source Type: journals

Association of BoLA-DRB3 alleles identified by a sequence-based typing method with mastitis pathogens in Japanese Holstein cowsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The association of the polymorphism of bovine leukocyte antigen (BoLA-DRB3) genes identified by the polymerase chain reaction sequence-based typing (PCR-SBT) method with resistance and susceptibility to mastitis caused by pathogenic bacteria was investigated. Blood samples for DNA extraction were collected from 194 Holstein cows (41 healthy cows and 153 mastitis cows including 24 mixed-infection cows infected with 2 or 3 species of pathogens) from 5 districts of Chiba prefecture, Japan. Sixteen BoLA-DRB3 alleles were detected. The 4 main alleles of DRB3*0101, *1501, *1201, and *1101 constituted 56.8% of the total number of...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Tatsuyuki YOSHIDA, Harutaka MUKOYAMA, Hiroki FURUTA, Yasuko KONDO, Shin-nosuke TAKESHIMA, Yoko AIDA, Motoaki KOSUGIYAMA, Hiroshi TOMOGANE Source Type: journals

Effect of different levels of Quebracho tannin on nitrogen utilization and growth performance of Najdi sheep fed alfalfa (Medicago sativa) hay as a sole dietEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A commercial tannin source (Quebracho tannin, QT), containing 75% condensed tannins (CT) in dry matter (DM) was used to evaluate the effects of addition of different levels of QT to alfalfa hay on the in vitro degradation kinetics of organic matter (OM) and nitrogen (N) in experiment 1 (Exp. 1), N utilization and microbial N synthesis (MNS) in experiment 2 (Exp. 2) and growth performance of growing Najdi lambs in experiment 3 (Exp. 3). Alfalfa hay was treated with QT at the levels of 0, 1, 2 and 3% of DM to form four treatments of QT0, QT1, QT2 and QT3 to have actual levels of CT being 0, 0.75, 1.5 and 2.25% of DM, respect...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Soliman N. AL-DOBAIB Source Type: journals

The effect of dietary ratios of corn silage and alfalfa hay on carbohydrate digestion and retention time of feed particles in the gastrointestinal tract of steersEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Four Holstein steers fitted with duodenal cannula were used in a 4 × 4 Latin square design to investigate the effect of the combination of corn silage (CS) and alfalfa hay (AH) in different ratios on the ruminal and intestinal digestion of carbohydrates and feed particle passage rate. Steers were fed mixed diets containing both CS and AH in ratios of 80:20, 60:40, 40:60 and 20:80 on a dry matter basis at 95% of ad libitum feed intake. The increase of AH proportion in diets increased dry matter intake and ruminal digestion of dry matter, non-fiber carbohydrate, neutral and acid detergent fiber linearly. Ruminal digestibili...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Taketo OBITSU, Masahiko GOTO, Toshihisa SUGINO, Kohzo TANIGUCHI, Kenichiro YUKIZANE, Shingo IMOTO, Mirei YANAGAWA, Mabrouk EL-SABAGH Source Type: journals

Immunohistochemical and scanning electron microscopic comparison of the collagen network constructions between pig, goat and chicken liversEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The distribution and three-dimensional architecture of collagen fibers were compared between pig, goat and chicken livers. Immunohistochemical staining revealed that collagen type I was identified in the interlobular connective tissue region and intralobular areas in pigs and goats. Type III collagen was also identified in the interlobular connective tissue region and intralobular sinusoidal walls. In the chicken liver, only the circumference region of the vessels was immunostained with collagen type I and III antibodies and the interlobular connective tissue wall could not be distinguished clearly. In the intralobular reg...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Shotaro NISHIMURA, Ayano SAGARA, Ichiro OSHIMA, Yoshitaka ONO, Hisao IWAMOTO, Kaoru OKANO, Hideyuki MIYACHI, Shoji TABATA Source Type: journals

A fine map for maternal lineage analysis by mitochondrial hypervariable region in 12 Chinese goat breedsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
As the fast pace of genomic research continues to identify mitochondrial lineages in animals, it has become apparent that many independent studies are needed to support a robust phylogenetic inference. The aim of this study was thus to further characterize the maternal lineage, proposed to originate in southwestern region of China, using a wider survey of diverse goat breeds in China. To this end, we sequenced the mitochondrial hypervariable region 1 (HVR1) of the mtDNA control region in 145 goats of 12 Chinese breeds. Phylogenetic analysis revealed that Chinese goats were classified into four distinct lineages (A, B, C an...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Yan-Ping WU, Wei-Jun GUAN, Qian-Jun ZHAO, Xiao-Hong HE, Ya-Bin PU, Jun-Hong HUO, Jin-Fang XIE, Jian-Lin HAN, Shao-Qi RAO, Yue-Hui MA Source Type: journals

Effects of dietary supplementation with conjugated linoleic acid on fatty acid composition and lipid oxidation in chicken breast meatEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this study, dietary CLA supplementation significantly increased the composition and content of CLA in chicken meat. The predominant CLA in meat from birds with supplemented diets was the cis-9, trans-11 isomer. The proportion of saturated fatty acid in meat significantly increased with increasing CLA supplementation, with a corresponding decrease in monounsaturated fatty acid. Dietary CLA also reduced thiobarbituric acid reactive substances (TBARS) values in raw meat during storage at 4°C for 5 days. These results provide evidence that CLA feeding is a practical strategy not only for adding nutritional benefits to chic...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Satoshi KAWAHARA, Shin-ichi TAKENOYAMA, Kazuaki TAKUMA, Michio MUGURUMA, Kiyoshi YAMAUCHI Source Type: journals

Effects of crossbreeding indigenous Hair Goat with Saanen on carcass measurements and meat quality of kids under an intensive production systemEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In conclusion, higher meat lightness values of crossbred kids, at particularly B1 level, might have a positive effect on the consumer choices.
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Alper YILMAZ, Bulent EKIZ, Mustafa OZCAN, Cuneyt KAPTAN, Hulya HANOGLU, Mesut YILDIRIR Source Type: journals

Effect of high moisture storage of pearl millet (Pennisetum typhoides) with or without feed enzymes on growth and nutrient utilization in broiler chickensEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Effect of reconstitution of pearl millet with or without enzymes on its utilization in broiler chickens was studied. The pearl millet grains were reconstituted by adding water to raise the moisture level to 30%, followed by storage in sealed plastic buckets with or without feed enzymes (0.5 g/kg) for 21 days at room temperature (25°C). Subsequently, the grains were sun-dried to reduce the moisture content up to 10% to avoid mould growth. Nine dietary treatments were formulated incorporating pearl millet either raw with or without enzymes or reconstituted with or without enzymes in maize-soya based control diet replacing m...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Satish Jagannath MANWAR, Asit Baran MANDAL Source Type: journals

Effects of maize (Zea mays L.) silage feeding on dry matter intake and milk production of dairy buffalo and cattle in Tarai, NepalEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
To identify the effects of whole crop maize silage (MS) as a substitute for rice straw (RS) on feed intake and milk production of mid-late lactating buffalo and cattle in Tarai, Nepal, eight Murrah and eight Jersey-Hariana were fed the basal diet, RS (ad libitum) with concentrate (0.68% of bodyweight [BW] on a dry matter [DM] basis). A 4 × 4 Latin square design experiment was conducted in each animal species with graded levels of MS substitution for RS (0%, T1; 33%, T2; 67%, T3 and 100%, T4). The MS had higher digestibility and total digestible nutrient (TDN) than RS. The DM intake per BW of the both species was highest i...
Source: Animal Science Journal - May 21, 2009 Category: Zoology Authors: Yoshiaki HAYASHI, Bhim B. THAPA, Mohan P. SHARMA, Maheshwor SAPKOTA, Hajime KUMAGAI Source Type: journals

Reproductive efficiency of Thoroughbred mares under Indian subtropical conditions: A retrospective survey over 7 years.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In conclusion, comparatively lower fertility rates were recorded in Thoroughbred mares bred under Indian subtropical climatic conditions than those reported from temperate regions that might be due to difference in breeding management rather than prevailing environment. PMID: 19505777 [PubMed - as supplied by publisher]
Source: Animal Reproduction Science - May 21, 2009 Category: Zoology Authors: Sharma S, Dhaliwal GS, Dadarwal D Tags: Anim Reprod Sci Source Type: journals

Social Evolution of Spatial Patterns in Bacterial Biofilms: When Conflict Drives DisorderEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We present a mechanistic model of cell growth at a surface, and we show that tension between growth and competition for nutrients can explain how empirically observed patterns emerge in biofilms. We then apply our model to evolutionary simulations and observe that the maintenance of patterns requires cooperation between cells. Specifically, when different genotypes meet and compete, natural selection favors energetically costly spreading strategies, like polymer secretion, that simultaneously reduce productivity and disrupt the spatial patterns. Our theory provides a formal link between higher‐level patterning and the po...
Source: The American Naturalist - May 20, 2009 Category: Zoology Tags: article Source Type: journals

Pollination Fluctuations Drive Evolutionary Syndromes Linking Dispersal and Mating SystemEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 46-55, July 2009. Abstract: The existence of a syndrome linking dispersal rate and mating system has long been debated in evolutionary ecology, especially in plants. Some verbal models hypothesize that the ability to self‐fertilize may be associated with high dispersal, since completely outcrossing species cannot reproduce when they disperse to an empty destination site. However, empirical observations fail to support a clear trend, and an association of high colonizing ability with high outcrossing has been reported. Here we develop a general metapopulation model ...
Source: The American Naturalist - May 20, 2009 Category: Zoology Tags: article Source Type: journals

Evolution of Predator and Prey Movement into Sink HabitatsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 68-81, July 2009. Abstract: Mathematical models of predator‐prey interactions in a patchy landscape are used to explore the evolution of dispersal into sink habitats. When evolution proceeds at a single trophic level (i.e., either prey or predator disperses), three evolutionary outcomes are observed. If predator‐prey dynamics are stable in source habitats, then there is an evolutionarily stable strategy (ESS) corresponding to sedentary phenotypes residing in source habitats. If predator‐prey dynamics are sufficiently unstable, then either an ESS corresponding t...
Source: The American Naturalist - May 20, 2009 Category: Zoology Tags: article Source Type: journals

Spectral Niche Complementarity and Carbon Dynamics in Pelagic EcosystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 141-147, July 2009. Abstract: Positive effects of biodiversity on ecosystem function are described from an increasing number of systems, but the underlying mechanisms frequently remain elusive. A truly predictive understanding of biodiversity–ecosystem function relationships requires the a priori identification of traits conferring specific (and possibly complementary) functions to individual species. Although planktonic organisms are responsible for approximately half of the world’s primary production, few studies have reported on the relationship between phytop...
Source: The American Naturalist - May 20, 2009 Category: Zoology Tags: article Notes and Comments Source Type: journals

Effect of winter torpor upon antioxidative defence in Helix pomatiaEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Anna Nowakowska, Grażyna Świderska-Kołacz, Justyna Rogalska, and Michał Caputa - Arousal of land snails from torpor is inseparably connected with an increase in oxygen consumption leading to oxidative stress. Therefore, activity of antioxidant defence system...
Source: Canadian Journal of Zoology - May 20, 2009 Category: Zoology Source Type: journals

Conformism in the food processing techniques of white-faced capuchin monkeys (Cebus capucinus).Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Researchers of "culture" have long been interested in the role of social learning in establishing patterns of behavioral variation in wild animals, but very few studies examine this issue using a developmental approach. This 7-year study examines the acquisition of techniques used to process Luehea candida fruits in a wild population of white-faced capuchin monkeys, Cebus capucinus, residing in and near Lomas Barbudal Biological Reserve, Costa Rica. The two techniques for extracting seeds (pounding or scrubbing) were approximately equal in efficiency, and subjects experimented with both techniques before settling on on...
Source: Animal Cognition - May 20, 2009 Category: Zoology Authors: Perry S Tags: Anim Cogn Source Type: journals

Do dogs (Canis familiaris) show contagious yawning?Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report an experimental investigation into whether domesticated dogs display contagious yawning. Fifteen dogs were shown video clips of (1) humans and (2) dogs displaying yawns and open-mouth expressions (not yawns) to investigate whether dogs showed contagious yawning to either of these social stimuli. Only one dog performed significantly more yawns during or shortly after viewing yawning videos than to the open-mouth videos, and most of these yawns occurred to the human videos. No dogs showed significantly more yawning to the open-mouth videos (human or dog). The percentage of dogs showing contagious yawning was less t...
Source: Animal Cognition - May 19, 2009 Category: Zoology Authors: Harr AL, Gilbert VR, Phillips KA Tags: Anim Cogn Source Type: journals

Support for a metapopulation structure among mammalsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We examined the literature for empirical evidence in support of the classical criteria set by Hanski (1999), and for the more lenient subset of criteria proposed by Elmhagen & Angerbjörn (2001). We suggest circumstances where metapopulation theory could be important in understanding population processes in mammals of different body sizes. The patchy distribution of large (>100 kg) mammals and dispersal often motivate inferences in support of a metapopulation structure. Published studies seldom address the full suite of classical criteria. However, studies on small mammals are more likely to record classic metapopulation c...
Source: Mammal Review - May 18, 2009 Category: Zoology Authors: PIETER I. OLIVIER, RUDI J. VAN AARDE, SAM M. FERREIRA Source Type: journals

Domestic cats (Felis catus) do not show causal understanding in a string-pulling task.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This study explored how domestic cats perform in a horizontal string-pulling task to determine whether they understand this case of physical causality. Fifteen cats were tested on their ability to retrieve an unreachable food treat in three different set-ups: (a) a single baited string, (b) two parallel strings where only one was baited and (c) two crossed strings where only one was baited. All cats succeeded at pulling a single string to obtain a treat, but none consistently chose the correct string when two strings were parallel. When tested with two crossed strings one cat chose the wrong string consistently and all oth...
Source: Animal Cognition - May 18, 2009 Category: Zoology Authors: Whitt E, Douglas M, Osthaus B, Hocking I Tags: Anim Cogn Source Type: journals

Horse (Equus caballus) whinnies: a source of social information.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Many animal species that rely mainly on calls to communicate produce individual acoustic structures, but we wondered whether individuals of species better known as visual communicants, with small vocal repertoires, would also exhibit individual distinctiveness in calls. Moreover, theoretical advances concerning the evolution of social intelligence are usually based on primate species data, but relatively little is known about the social cognitive capacities of non-primate mammals. However, some non-primate species demonstrate auditory recognition of social categories and possess mental representation of their social ne...
Source: Animal Cognition - May 18, 2009 Category: Zoology Authors: Lemasson A, Boutin A, Boivin S, Blois-Heulin C, Hausberger M Tags: Anim Cogn Source Type: journals

Learning, memorizing and apparent forgetting of chemical cues from new predators by Iberian green frog tadpoles.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Many antipredator adaptations are induced by the prey's ability to recognize chemical cues from predators. However, predator recognition often requires learning by prey individuals. Iberian green frog tadpoles (Pelophylax perezi) have the ability to learn new potential predators. Here, we tested the memory capabilities of Iberian green frog tadpoles. We conditioned tadpoles with chemicals cues from a non-predatory fish in conjunction with conspecific alarm cues, and examined whether tadpoles retained their conditioned response (reduction of activity level). We found that conditioned tadpoles reduced their activity leve...
Source: Animal Cognition - May 18, 2009 Category: Zoology Authors: Gonzalo A, López P, Martín J Tags: Anim Cogn Source Type: journals

Recognition of a 3D snake model and its 2D photographic image by captive black tufted-ear marmosets (Callithrix penicillata).Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Two-dimensional (2D) displays of real three-dimensional (3D) objects are frequently used experimental tools in animal studies. Whether marmoset monkeys, with their highly diverse and complex anti-predation strategies, readily recognized 2D representations of potential threats has yet to be determined, as seen in other primates. Thus, the behavioral responses of adult captive black tufted-ear marmosets (Callithrix penicillata) toward an unfamiliar motionless snake-model and its photograph were assessed. Pictorially naïve subjects were randomly divided into two groups (n = 12/each) and submitted to two trials. Group...
Source: Animal Cognition - May 18, 2009 Category: Zoology Authors: Emile N, Barros M Tags: Anim Cogn Source Type: journals

Comparison of two methods of synchronization of estrus in brown brocket deer (Mazama gouazoubira).Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This study aimed to establish a protocol for synchronization of estrus in brown brocket deer (Mazama gouazoubira). Two groups of hinds (n=3) were submitted to two different protocols: Treatment 1 received an intravaginal progesterone (CIDR((R))) device for 8 days, followed by 265mug injection of cloprostenol at the time of removal; and Treatment 2 received two injections of 265mug of cloprostenol 11 days apart. After 30 days, each group of three hinds received the other treatment. Treatment efficacy was evaluated by reproductive behavior, fecal progestin and estrogen concentration and the observation of CL by laparoscopy 6...
Source: Animal Reproduction Science - May 18, 2009 Category: Zoology Authors: Zanetti ED, Polegato BF, Duarte JM Tags: Anim Reprod Sci Source Type: journals

Cotyledonary responses to maternal selenium and dietary restriction may influence alterations in fetal weight and fetal liver glycogen in sheep.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
To examine the effects of maternal supranutritional selenium (Se) and nutrient restriction during mid and late gestation on placental characteristics and fetal liver glycogen, ewes received either adequate Se (ASe) or high Se (HSe) prior to breeding. On d 64 of gestation, ASe and HSe ewes remained at 100% of requirements (controls; CON) or were restricted (RES; 60% of requirements). On d 135 of gestation, fetal weight (P</=0.08) was greatest in both HSe and CON ewes. Placentome number, mass, and caruncular and cotyledonary weight were not different (P>/=0.17) among treatments. Fetal mass:placental mass ratio was ...
Source: Animal Reproduction Science - May 18, 2009 Category: Zoology Authors: Lekatz LA, Ward MA, Borowicz PP, Taylor JB, Redmer DA, Grazul-Bilska AT, Reynolds LP, Caton JS, Vonnahme KA Tags: Anim Reprod Sci Source Type: journals

Synthesis and characterization of biologically active recombinant elk and horse FSH.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The objective of this investigation was to clone and express the elk and horse common alpha-subunit and FSH beta-subunit cDNAs, and to produce recombinant FSH from both species in vitro. The RNAs extracted from elk and horse pituitary glands were reverse-transcribed and amplified by polymerase chain reaction. The cDNAs corresponding to both subunits of elk and horse were cloned into the expression vector pBudCE4.1((R)) and transfected into CRL-9096 cells. Expression of both genes was determined in the transfected cells by Northern and Western blot analysis. Recombinant elk and horse FSH secreted in culture media were chara...
Source: Animal Reproduction Science - May 18, 2009 Category: Zoology Authors: Fachal MV, Furlan M, Clark R, Card CE, Chedrese PJ Tags: Anim Reprod Sci Source Type: journals

Environmental Sensitivity in Relation to Size and Sex in Birds: Meta‐Regression AnalysisEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We examined support for these hypotheses through the use of meta‐analytic techniques based on the published literature on avian species. Our results revealed small, nonsignificant effects for hypotheses of size‐ and sex‐dependent susceptibilities alone. Application of a multivariate meta‐analytic technique (meta‐regression) suggests a joint influence of sexual size dimorphism and clutch size in explaining sex‐specific patterns of vulnerability. These findings suggest that none of the proposed hypotheses tested here on their own can sufficiently explain the observed patterns and that additional factors must be c...
Source: The American Naturalist - May 15, 2009 Category: Zoology Tags: article Source Type: journals

Ecology Shapes Birdsong Evolution: Variation in Morphology and Habitat Explains Variation in White‐Crowned Sparrow SongEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 24-33, July 2009. Abstract: Ecological variation appears to underlie the evolution of mating signals in many taxa, yet understanding of how this process occurs over time is limited. Here, I investigate whether changes over time in a well‐studied mating signal—birdsong—are attributable to ecological factors that affect signal production and transmission. Variation in the acoustic properties of songs is thought to be affected by the mechanics of sound production as well as by features of the habitat that affect sound transmission. To determine whether these mecha...
Source: The American Naturalist - May 14, 2009 Category: Zoology Tags: article Source Type: journals

Adaptive Changes in Life History and Survival following a New Guppy IntroductionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 34-45, July 2009. Abstract: Numerous studies of wild populations have shown that phenotypic traits can change adaptively on short timescales, but very few studies have considered coincident changes in major fitness components. We here examine adaptive changes in life‐history traits and survival rates for wild guppies introduced into new environments. Female life‐history traits in the derived (Damier River) populations diverged from the ancestral (Yarra River) population, as a result of adaptation to predation regime (high vs. low) and other aspects of the local r...
Source: The American Naturalist - May 13, 2009 Category: Zoology Tags: article Source Type: journals

Indirect Population Dynamic Benefits of Altered Life‐History Trade‐Offs in Response to Egg HarvestingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 111-121, July 2009. Abstract: Variations in demographic rates due to differential resource allocation between individuals are important considerations in the development of accurate population dynamic models. Systematic harvesting can alter age structure and/or reduce population density, conferring indirect positive benefits on the source population as a result of a consequent redistribution of resources between the remaining individuals. Independently of effects mediated through changes in density and competition, demographic rates can also be influenced by within�...
Source: The American Naturalist - May 13, 2009 Category: Zoology Tags: article Source Type: journals

Morphology of the rectal gland of the spiny dogfish (Squalus acanthias) shark in response to feedingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Victoria Matey, Chris M. Wood, W. Wesley Dowd, Dietmar Kültz, and Patrick J. Walsh - The morphology of the rectal gland was examined in spiny dogfish (Squalus acanthias L, 1758) sharks fasted (1 week) or 6 and 20 h postfeeding. The morphology...
Source: Canadian Journal of Zoology - May 11, 2009 Category: Zoology Source Type: journals

Breeding-site selection by the poison frog Ranitomeya biolat in Amazonian bamboo forests: an experimental approachEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Rudolf von May, Margarita Medina-Müller, Maureen A. Donnelly, and Kyle Summers - Habitat selection in amphibians has typically been investigated using species that breed in medium-sized to large bodies of water. So far, few studies have focused...
Source: Canadian Journal of Zoology - May 11, 2009 Category: Zoology Source Type: journals

Sperm performance under hypoxic conditions in the intertidal fish Porichthys notatusEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
John L. Fitzpatrick, Paul M. Craig, Carol Bucking, Sigal Balshine, Chris M. Wood, and Grant B. McClelland - Hypoxia (low oxygen) exposure generally leads to decreased reproductive capacity, exhibited by reductions in testicular mass, reproductive hormones, and sperm swimming speed. However, in many...
Source: Canadian Journal of Zoology - May 11, 2009 Category: Zoology Source Type: journals

Sexual size dimorphism in caecilian amphibians: analysis, review and directions for future research.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this study, sexual size dimorphism in the oviparous caecilian Ichthyophis cf. kohtaoensis, a phylogenetically basal caecilian, was analysed. Females were larger in all body and head characters tested. However, when adjusted to body size (total length), females differed only in their cloacal shape. Clutch volume was positively correlated to female body size, thus female fecundity increased with body size supporting the hypothesis of a fecundity-selected SSD in the oviparous Ichthyophis cf. kohtaoensis. A review of the present SSD data for caecilians shows that many species are monomorphic for body size but show dimorphis...
Source: Zoology - May 9, 2009 Category: Zoology Authors: Kupfer A Tags: Zoology (Jena) Source Type: journals

Development of the ovary and ontongeny of mRNA and protein for P450 aromatase (arom) and estrogen receptors (ER) alpha and beta during early fetal life in cattle.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Estradiol-17beta is the predominant steroid produced during early stages of ovarian development in ruminants and steroid hormones have been hypothesized to regulate ovigerous cord formation, germ cell meiosis and ovarian vascular development. Therefore, the objective was to determine the presence and localization of mRNA and protein encoding cytochrome P450 aromatase (P450arom), and estrogen receptors alpha (ERalpha) and beta (ERbeta) during ovarian development in fetuses of cattle on days 35, 45, 60, 75, 90 and 105 after breeding (n=4/age) using in situ hybridization and immunohistochemistry. No ovarian tissue was fou...
Source: Animal Reproduction Science - May 9, 2009 Category: Zoology Authors: Garverick HA, Juengel JL, Smith P, Heath DA, Burkhart MN, Perry GA, Smith MF, McNatty KP Tags: Anim Reprod Sci Source Type: journals

Influence of the length of proestrus on fertility and endocrine function in female cattle.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In conclusion, decreasing the length of proestrus before induction of ovulation of a large follicle resulted in lesser pregnancy rates and an increased incidence of short luteal phases. The impact of a shortened proestrus on concentrations of progesterone in cows with luteal phases of normal length varied among experiments. Decreased circulating concentrations of estradiol during the preovulatory period and/or reduced concentrations of progesterone during the subsequent estrous cycle in cows that do not experience a shortened luteal phase may represent the mechanism responsible for reduced fertility with the SPE treatment....
Source: Animal Reproduction Science - May 9, 2009 Category: Zoology Authors: Bridges GA, Mussard ML, Burke CR, Day ML Tags: Anim Reprod Sci Source Type: journals

Contraceptive efficacy of a novel intrauterine device (IUD) in white-tailed deer.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Overabundant white-tailed deer (Odocoileus virginianus) pose risks to property, health, and safety of human beings. Public concerns about lethal management can impair efforts to address these issues, particularly in urban settings. Several techniques developed for reducing reproductive output of deer have limited utility because they require repeated dosing to achieve permanent effect and face uncertain regulatory approval for use beyond experimentation. From 10 August 2006 through 30 December 2007, we evaluated the contraceptive efficacy of copper-containing intrauterine devices (IUDs) implanted trans-cervically in wh...
Source: Animal Reproduction Science - May 9, 2009 Category: Zoology Authors: Malcolm KD, Van Deelen TR, Drake D, Kesler DJ, Vercauteren KC Tags: Anim Reprod Sci Source Type: journals

Variability of CAG tandem repeats in exon 1 of the androgen receptor gene is not related with dog intersexuality.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Numerous mutations of the human androgen receptor (AR) gene cause an intersexual phenotype, called the androgen insensitivity syndrome. The intersexual phenotype is also quite often diagnosed in dogs. The aim of this study was to conduct a comparative analysis of the entire coding sequence (eight exons) of the AR gene in healthy and four intersex dogs, as well as in three other canids (the red fox, arctic fox and Chinese raccoon dog). The coding sequence of the studied species appeared to be conserved (similarity above 97%) and polymorphism was found in exon 1 only. Altogether, 2 SNPs were identified in healthy dogs, 1...
Source: Animal Reproduction Science - May 9, 2009 Category: Zoology Authors: Nowacka-Woszuk J, Switonski M Tags: Anim Reprod Sci Source Type: journals

Scaling of feeding biomechanics in the horn shark Heterodontus francisci: ontogenetic constraints on durophagy.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Organismal performance changes over ontogeny as the musculoskeletal systems underlying animal behavior grow in relative size and shape. As performance is a determinant of feeding ecology, ontogenetic changes in the former can influence the latter. The horn shark Heterodontus francisci consumes hard-shelled benthic invertebrates, which may be problematic for younger animals with lower performance capacities. Scaling of feeding biomechanics was investigated in H. francisci (n=16, 19-59cm standard length (SL)) to determine the biomechanical basis of allometric changes in feeding performance and whether this performance ca...
Source: Zoology - May 8, 2009 Category: Zoology Authors: Kolmann MA, Huber DR Tags: Zoology (Jena) Source Type: journals

Effects of diets containing alfalfa hay or barley flour mixed alfalfa silage on feeding behavior, productivity, rumen fermentation and blood metabolites in lactating cowsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The effects of barley flour on the fermentation parameters of alfalfa silage and on the productivity of dairy cows were investigated. Alfalfa forage was ensiled either with or without barley flour. Barley flour was soaked in water for 24 h before being mixed with alfalfa (12 kg: 100 kg dry matter bases) at ensiling. Eighteen multi-parous cows were assigned to three equal treatment groups using a completely randomized design. Three isocaloric and isonitrogenous total mixed rations containing alfalfa hay, ordinary alfalfa silage or barley flour mixed alfalfa silage were then prepared. The concentrations of ammonia nitrogen, ...
Source: Animal Science Journal - May 8, 2009 Category: Zoology Authors: Ali-Akbar KHADEM, Majid SHARIFI, Ahmad AFZALZADEH, Mohammad REZAEIAN Source Type: journals

Fire Drives Transcontinental Variation in Tree Birch Defense against Browsing by Snowshoe HaresEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The American Naturalist, Volume 174, Issue 1, Page 13-23, July 2009. Abstract: Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates variation in the abundance of early successional plants that snowshoe hares eat in winter, leading to geographic variation in hare density. We hypothesize that fire is the template for a geographic mosaic of natur...
Source: The American Naturalist - May 7, 2009 Category: Zoology Tags: article Source Type: journals

Four noble questionsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Source: Ethology - May 6, 2009 Category: Zoology Source Type: journals

Lysosomal and alkaline phosphatase activity indicate macromolecule transport across the uterine epithelium in two viviparous skinks with complex placenta.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this study, we identified an extensive formation of a lysosomal system in the apical region of uterine epithelial cells in the highly secretory omphaloplacental region of the skink placenta in two species from the Pseudemoia genus. We suggest that this lysosomal system assists apocrine secretion by digesting large macromolecules into smaller particles, allowing more effective transport across the plasma membrane of uterine epithelial cells. We also demonstrate alkaline phosphatase (AP) activity along the apical plasma membrane of uterine epithelial cells in the omphaloplacental region of skink uterus, an enzyme usually ...
Source: Journal of Experimental Zoology. Part B. Molecular and Developmental Evolution - May 6, 2009 Category: Zoology Authors: Biazik JM, Thompson MB, Murphy CR Tags: J Exp Zoolog B Mol Dev Evol Source Type: journals

Field metabolic rate and water turnover of red kangaroos and sheep in an arid rangeland: an empirically derived dry-sheep-equivalent for kangaroosEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A. J. Munn, T. J. Dawson, S. R. McLeod, D. B. Croft, M. B. Thompson, C. R. Dickman - Volume 57(1)
Source: Australian Journal of Zoology - May 5, 2009 Category: Zoology Source Type: journals

Refining the polytypic species concept of mangrove monitors (Squamata: Varanus indicus group): a new cryptic species from the Talaud Islands, Indonesia, reveals the underestimated diversity of Indo-Australian monitor lizardsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
André Koch, Evy Arida, Andreas Schmitz, Wolfgang Böhme, Thomas Ziegler - Volume 57(1)
Source: Australian Journal of Zoology - May 5, 2009 Category: Zoology Source Type: journals

Immunolocalization of lingual antimicrobial peptide (LAP) in the bovine mammary glandEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Lingual antimicrobial peptide (LAP), a member of the [beta]-defensin family in cows, is involved in the innate immune system and plays a crucial role in killing a large variety of microorganisms. The aim of the present study was to demonstrate the immunolocalization of LAP in the mammary glands of cows. A LAP antibody was raised in a rabbit by immunity with a synthetic 11 amino acid sequence out of a 42-amino acid sequence of the mature form of LAP. The specificity of the LAP antibody was checked using a competitive immunoassay and Western blotting. Paraffin sections of the mammary gland were immunostained with LAP antibod...
Source: Animal Science Journal - May 5, 2009 Category: Zoology Authors: Naoki ISOBE, Kenji HOSODA, Yukinori YOSHIMURA Source Type: journals

Brewer's yeast efficiently degrades phytate phosphorus in a corn-soybean meal diet during soaking treatmentEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Microbes such as yeast and Aspergillus are known to produce phytase, and Aspergillus phytase has been used as a feed additive for improving phytate-phosphorus bioavailability in monogastric animals. We measured phytase activity in some by-products from fermented food and beverage productions by yeast and Aspergillus. The phytase activity was as high as 3577 and 2225 PU/kg DM in raw and dried brewer's yeasts, respectively. On the other hand, the phytase activity was approximately 400 PU/kg DM in white-wine yeast and red-wine yeast. The phytase activity was further low in natto (fermented soybean) residue, soy sauce cake, ri...
Source: Animal Science Journal - May 5, 2009 Category: Zoology Authors: Gyo-Moon CHU, Hideyuki OHMORI, Tomoyuki KAWASHIMA, Masayuki FUNABA, Tohru MATSUI Source Type: journals

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