bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of wind and temperature on the catch rate of the American lobster (Homarus americanus) during spring fisheries off eastern Canada
Authors: DRINKWATER K. F. , TREMBLAY M. J. , COMEAU M. 
Published: November 2005

AbstractThe effects of wind and temperature on catch rate of American lobster (Homarus americanus) in the Baie des Chaleurs and off Cape Breton Island in Eastern Canada were investigated. Data on lobster catch and the number of trap hauls were available through a fishermen's volunteer logbook program, bottom temperatures were measured from thermistors either moored nearby or placed inside lobster traps and wind measurements were obtained from local airports. In the Baie des Chaleurs and off the east coast of Cape Breton, a positive and significant correlation was found between the mean temperature change during the 24 h prior to the traps being hauled and the change in the average catch of lobsters per trap haul. Catch rates rose with increasing bottom temperatures and fell with declining bottom temperatures. Higher correlations between changes in temperature and catch rates occurred at sites where the temperature variance was greater. The short‐term fluctuations in lobster catch rates corresponding to temperature changes are hypothesized to result from behavioral changes affecting lobster activity. In both study areas, the large temperature variability was mainly forced by alongshore winds producing upwelling and downwelling, consistent with a classical Ekman response. The effect of the winds on lobster catch is shown to be principally due to their influence on ocean bottom temperatures. Along the south coast of Cape Breton, no relationship was found between catch rates and either temperature or wind, perhaps because lower lobster abundance resulted in a lower signal‐to‐noise ratio. The results of this study qualitatively support the observations by fishermen of a wind‐induced effect on lobster catch rates.
Flower colour phenology in British mesotrophic grassland communities
Authors: Warren J. , Billington T. 
Published: November 2005

AbstractDescriptions of anthropocentric phenologies of flower colour were obtained for all thirteen British mesotrophic grassland communities, defined by the National Vegetation Classification. They were obtained by combining information on species abundance with data on flowering time and flower colour. Although the results are crude estimates, they clearly demonstrate that grassland communities differ in their floral phenologies with yellow‐flowered species being significantly most abundant, and blue‐flowered species being least abundant than the colours of other flowering species in British grasslands. The peak months for flowering were June and July. Significant interactions were observed between community type and flower colour; community type and month; and flower colour and month. These interactions may be explained by ecological differences between the communities, for example hay meadows flowered earlier than other grassland types. It is argued that other differences between communities in their floral phenologies, for example the absence of blue flowers from the agriculturally improved MG7 and MG11 swards, may support the hypothesis that the limited availability of pollination niches may affect plant community structure.
Nitrogen fertilizer application and developmental stage affect silage quality of timothy (Phleum pratense L.)
Authors: Tremblay G. F. , Bélanger G. , Drapeau R. 
Published: November 2005

AbstractCrop composition at harvest affects the ensiling process and the resulting silage quality. The objectives of this study were to determine: (i) the effect of annual N‐fertilizer application (0, 60, 120 and 180 kg N ha−1) and developmental stage (stem elongation, early heading, late heading and early flowering) on the ensiling properties and silage quality of the spring regrowth of timothy (Phleum pratense L.) at two sites for 1 or 2 years, and (ii) the relationship between ensiling properties of the forage and the quality of the resulting silage. Laboratory silos with wilted forage at approximately 350 g dry matter (DM) kg−1 of fresh matter were prepared at each harvest and opened 150 d later for silage analysis. Higher rates of N‐fertilizer application decreased the concentration of water‐soluble carbohydrates (WSC), increased the buffering capacity (BC) and nitrate concentration, and decreased the ratio of WSC:BC, primarily in the early stages of development. The ensiling properties of timothy were, therefore, less favourable when high rates of N fertilizer were applied. Silage pH generally increased with increasing rates of N‐fertilizer application; this increase was particularly evident at the first three developmental stages at one site in 1 year. Non‐protein N (NPN) and soluble N concentrations of the silages increased with increased rates of N‐fertilizer application at the first three developmental stages but decreased at early flowering. Ammonia‐N concentration in the silages increased by 0·85, 0·56 and 0·67 when rates of N‐fertilizer application were 60, 120 and 180 kg ha−1, respectively, compared with that when no N fertilizer was applied. Significant correlations between the composition of the forage ensiled and silage quality variables were found at sites in individual years but, when all data were combined, WSC concentration and BC, and their ratio in the forages, were not correlated with pH, and soluble‐N and ammonia‐N concentrations of the silages, and were weakly correlated with NPN and free amino acid‐N concentrations of the silages. Silage quality was reduced by increased N‐fertilizer application, primarily at the early developmental stages, and this can be attributed to a reduction in WSC concentration and an increase in BC of the forage. Water‐soluble carbohydrate concentration, BC, and their ratio, however, were poor predictors of silage quality.
Seasonal patterns of diet composition, herbage intake and digestibility identify limitations to performance of weaner sheep grazing native pasture in the Falkland Islands
Authors: Miller S. M. , Thompson R. P. 
Published: November 2005

AbstractThe botanical composition, intake and digestibility of the diet consumed by 1‐year‐old weaner sheep grazing a native white grass plant community in the Falkland Islands was measured in five periods between June 1998 and March 1999. Five different sheep were used in each period. Two methods were used for estimating the botanical composition of the diet: plant cuticle patterns in the faeces of the sheep and the patterns of concentrations of n‐alkanes in the faeces of sheep. These methods were used to predict the concentrations of C32‐ and C33‐alkanes in the herbage to allow the estimation of herbage intake and digestibility using the n‐alkane technique. It was concluded that the n‐alkane technique gave more accurate estimates of diet composition based on the comparison with estimates of nutrient intake derived from liveweight gains of sheep. The dominant pasture species, Cortaderia pilosa, was the predominant species consumed during the cooler periods of the year. In the summer, when the highest liveweight gains of sheep occur, the proportion of fine grass species, including Poa spp., Festuca magellanica and Agrostis capillaris, and herbs and sedges in the diet was highest. Herbage intake was the highest during the summer periods when digestibility was also at its peak. Estimated nutritional deficiencies of metabolizable energy, crude protein, phosphorus and vitamin D3 that limit the growth and development of weaner sheep were evident for up to 9 months of the year. Targeted supplementation regimes that counter specific nutrient deficiencies could be developed on the basis of these results to address critical periods in the growth of young sheep.
A model describing the utilization of herbage by cattle in a rotational grazing system
Authors: Brereton A. J. , Holden N. M. , McGilloway D. A. , Carton O. T. 
Published: November 2005

AbstractA model that describes the utilization of herbage by cattle in a rotational grazing system is presented. The model considers swards as being structured into two phases: a long phase associated with old dung patches, and a short phase. Both phases are treated as consisting of a series of horizontal strata corresponding in depth to a bite depth. The sward is divided into feeding stations consisting of either the long or the short phase. In each, only the surface stratum is available for grazing at each time step. At any time step, the individuals of a herd of cattle, distributed at random, encounter the entire range of strata. The rate of intake of each member of the herd depends on the intake properties of the stratum that it has encountered. The number of cattle that encounter each stratum type is variable so that the mean intake per member of the herd is the weighted mean. The core feature of the model is the simulation of the change over time in the frequency distribution of exposed stratum types and the distribution of grazing across this range of strata. The members of the herd are assumed to select a feeding station based on preference for leafiness of the encountered stata and the phase. The decision to graze or not is based on the comparison between the current vs. the previous feeding station. Model parameter values were based on published data. The proportion of leaf and bulk density of a phase or the strata were determined from an analysis of a sample of sward profiles. Using bite dimension, bite weight, biting rate, search time, feeding station area and selective behaviour, it was possible to simulate sward depletion that is very similar to the observed data from grazed paddocks in experiments in south‐east Ireland. The model of herbage utilization adequately described the changes in intake and sward structure during grazing and it was concluded that it was suitable for use as part of a simulation of a grazing system.
Comparison of haymaking strategies for cow‐calf systems in the Salado Region of Argentina using a simulation model. 1. Effect of herbage mass at cutting and cow stocking rate under a rigid system of management
Authors: Romera A. J. , Morris S. T. , Hodgson J. , Stirling W. D. , Woodward S. J. R. 
Published: November 2005

AbstractA simulation model was used to compare the long‐term performance of cow‐calf farm systems under different haymaking strategies on a 100‐ha farm. In the simulation, farm management was based on that which had been developed on Reserva 6, an experimental cow‐calf farm established in 1966 at Instituto Nacional de Tecnología Agropecuaria‐Balcarce Experimental Station, Argentina, where different technologies, including haymaking, have been adapted and applied in order to increase productivity of cow‐calf systems in the Salado Region of Argentina. The management of the system is based on a restricted mating season (2 months), early weaning (5–7 months of age) and forage conservation. The simulations showed that the effect of using hay with respect to the strategy without hay, in terms of calf liveweight (LW) production per hectare, was greatest at the cow numbers that maximized production (290–320 cows) with a proportionate increase of 0.25. On the other hand, the advantage of using hay was smallest when the herbage mass at cutting for hay was 6 t dry matter (DM) ha−1, particularly when more than 0.50 of the farm area was allocated to haymaking. The differences among the haymaking policies increased with cow numbers, especially at high herbage masses at cutting for hay. The analysis also suggested that the LW production per hectare of cow‐calf farms would be maximized by harvesting 0.40–0.50 of the total farm area and aiming to cut hay at a herbage mass of 4 t DM ha−1 and with medium quality.
Comparison of haymaking strategies for cow‐calf systems in the Salado Region of Argentina using a simulation model. 2. Incorporation of flexibility into the decision rules
Authors: Romera A. J. , Morris S. T. , Hodgson J. , Stirling W. D. , Woodward S. J. R. 
Published: November 2005

AbstractIn pastoral farming systems, pasture production normally exceeds demand in the spring–summer period. Consequently, conserving forage at this time for use during the following winter is a widespread practice. The objective of this study was to assess the possible advantages of incorporating flexibility into a calendar‐based haymaking policy. A range of flexible haymaking strategies were simulated and compared against a calendar‐based strategy by using a simulation model to estimate long‐term performance of cow‐calf farm systems under each strategy. The results suggest that controlling haymaking in a flexible fashion, basing the decisions of closing, releasing and cutting paddocks on a simple pasture budget, could give the system productive advantages over using a calendar‐based approach. In terms of liveweight production per hectare, compared at the same area harvested, the flexible approach had higher average annual calf liveweight production (an increase of up to 0.15) and lower system variability [a reduction of 0.10 in the coefficient of variation (CV)] depending on the stocking rate. The results indicated that allocating more than 0.50–0.60 of the farm area to conservation would only be advantageous at very high stocking rates. In contrast to the calendar‐based strategy, making more hay than required for the immediate next winter, where possible, can reduce system variability.
Regulation of MT1 Melatonin Receptor Expression in the Foetal Rat Pituitary
Authors: Johnston J. D. , Klosen P. , Barrett P. , Hazlerigg D. G. 
Published: November 2005

AbstractDuring development, melatonin receptors are transiently expressed in multiple neuroendocrine tissues, suggesting a novel role for melatonin in developmental physiology. The best characterised model of melatonin signalling during development is the pars distalis of the rat pituitary. However, although many studies have characterised the postnatal decline of melatonin receptors in the rat pars distalis, the mechanism(s) that time the developmental onset of receptor expression during embryogenesis are unknown. Analysis of these mechanisms may yield important information regarding the putative role of melatonin in neuroendocrine development. Here, we report the expression of MT1 melatonin receptor mRNA in the rat pituitary from embryonic day 15.5 (e15.5). Prior to e15.5, the homeodomain transcription factor Msx‐1, an inhibitor of cellular differentiation, is widely expressed throughout the pituitary. In transient transfection experiments, Msx‐1 potently inhibited pituitary homeobox‐1 (Pitx‐1)‐induced MT1 promoter activity and therefore may represent a key inhibitor of MT1 expression in early pituitary development. During late embryogenesis, MT1 mRNA was expressed in both the ventral and dorsal pituitary. Analysis of a 1.5‐kb fragment of the rat MT1 promoter revealed four putative cis‐elements for the POU domain factor Pit‐1, which is associated with mid‐dorsal cell lineages. Although Pit‐1 induced a strong, dose‐dependent stimulation of MT1 promoter activity in vitro, dual‐labelled in situ hybridisation revealed no colocalisation of MT1 and Pit‐1 mRNAs in vivo at e19.5. By contrast, all MT1 positive cells colocalised with αGSU and most with βTSH mRNA. Our data therefore implicate the decline of Msx‐1 expression as a key event that times the onset of melatonin receptor expression to the differentiation of endocrine cells types in the developing pituitary gland, and suggest that the melatonin‐sensitive cells in the embryonic pituitary are primarily Pit‐1‐independent thyrotrophs in the rostral pituitary, with a secondary population of pars distalis gonadotrophs.
Attenuation of Fever At Near Term: Is Interleukin‐6–STAT3 Signalling Altered?
Authors: Harré E.‐M. , Mouihate A. , Pittman Q. J. 
Published: November 2005

AbstractPregnant rats in late gestation show a reduced fever response after stimulation with lipopolysaccharide (LPS). This can result from either an increased action of endogenous antipyretics or a reduction in the production or action of endogenous pyrogens. Nonpregnant rats given LPS release interleukin (IL)‐6, which causes nuclear translocation of the signal transducer and activator of transcription 3 (STAT3) in the vascular organ of the lamina terminalis (OVLT), followed by a significant increase in core body temperature. The present study investigated whether the reduced fever response in near‐term pregnant rats is associated with a reduced nuclear STAT3 response. Rats at gestation day 15 (G15), gestation day 21 (G21, near term) and at lactation day 5 (L5) were injected with LPS (50 µg/kg, i.p.) or vehicle. Only near‐term pregnant rats responded with an attenuated body temperature during the fever response. Immunohistological analysis indicated no significant difference in nuclear STAT3 in the OVLT of the different animal groups 2 h after LPS. Measurement of total and phosphorylated STAT3 protein in the OVLT with semiquantitative western blot revealed no significant differences of this protein among these immune challenged animal groups. IL‐6 concentrations were also similar at G15, G21 and L5 2 h after injection of LPS. These results lead to the conclusion that the attenuation of the fever response at near‐term pregnancy is not associated with a reduced amount of nuclear STAT3 in the OVLT, indicating a maintained IL‐6–STAT3 signalling pathway in the OVLT.
Uveodermatologic (VKH‐like) syndrome in American Akita dogs is associated with an increased frequency of DQA1*00201
Authors: Angles J. M. , Famula T. R. , Pedersen N. C. 
Published: November 2005

AbstractThe Akita breed of dog is affected by a number of distinct immune‐mediated diseases, including thyroiditis, sebaceous adenitis, pemphigus foliaceus, uveitis, polyarthritis, myasthenia gravis, and uveodermatologic (UV) syndrome. UV syndrome is manifested by progressive uveitis and depigmenting dermatitis that closely resembles the human Vogt – Koyanagi – Harada syndrome. This study examined the allelic diversity of the three DLA class II loci (DRB1, DQA1, and DQB1) in the American Akita dog, and the relationship of specific DLA class II alleles to the UV. Low allelic variation was demonstrated within genes of DLA class II. American Akita dogs possessed six of the reported 16 DQA1 alleles, but only eight of 61 reported alleles in DRB1 and nine of 47 reported alleles in DQB1. Almost one‐half of American Akita dogs were homozygous for a single allele at DQA1 and up to a quarter at DRB1 and DQB1. DLA‐DQA1*00201 was associated with a significantly higher relative risk (RR = 15.3) or odds ratio (OR = 15.99) for UV syndrome than other DLA class II alleles. No significant association was noted with haplotypes of DRB1, DQB1, and DQA1 alleles; DRB1*03201‐DQA1*00201 trended toward significance. This study confirmed loss of DLA genetic diversity in the American Akita dog in common with other pure breeds of dog and suggested a role for certain DLA class II gene alleles in the pathogenesis of UV.
Administration of hCG 5 days after Breeding and Reproductive Performance in Nulliparous Dairy Goats
Authors: Fonseca JF , Torres CAA 
Published: November 2005

ContentsThe objective of this study was to investigate the effect of hCG administration 5 days after breeding on plasma progesterone (P4) concentration and reproductive performance of oestrous‐induced nulliparous dairy goats. A total of 59 nulliparous goats (36 Alpine and 23 Saanen) received intravaginal sponges with 60 mg medroxyprogesterone acetate for 9 days plus 200 IU equine chorionic gonadotrophin (eCG) and 22.5 μg d‐cloprostenol 24 h before sponge removal. After detection of oestrus (day of oestrus = day 0) and breeding, 49 females were randomly assigned, according to the breed, into two treatments (T1 and T2). In T1 (n = 25) and T2 (n = 24), animals received intramuscular injection of 1 ml of saline solution (control) or 250 IU hCG, respectively, 5 days after breeding. Plasma P4 concentration (ng/ml) was determined from blood sampled on days 0, 5, 7, 13, 17, 21, 28 and 45 after breeding. Animals were scanned by transrectal ultrasound (5 MHz probe) on days 35 and 70 after breeding for detection of pregnancy. Plasma P4 concentration did not differ (p > 0.05) between treatments in all days, but it was increased (p < 0.05) in Saanen than in Alpine goats from days 13 to 45. Pregnancy and parturition rates, litter size and gestation period were similar (p > 0.05) to treatments and breeds. Results of this study indicate that human chorionic gonadotrophin (hCG) administration 5 days after breeding did not significantly alter reproductive performance in dairy nulliparous goats and that plasma P4 differed between Saanen and Alpine goats.
Boar Taint is Related to Endocrine and Anatomical Changes at Puberty but not to Aggressive Behaviour in Entire Male Pigs
Authors: Zamaratskaia G , Rydhmer L , Chen G , Madej A , Andersson HK , Lundström K 
Published: November 2005

ContentsThis study aimed to describe the association between incidence of boar taint and pubertal changes in gonadal hormones, size of reproductive organs and aggressive behaviour in entire male pigs. In total, 111 entire male pigs were included in the study. Sampling was performed first at 90 kg live weight (LW) and, then, at 115 kg LW. Variables measured were skatole and androstenone levels in plasma and fat, testosterone and oestrone sulphate in plasma, free oestrone in fat, weight of testes and length of bulbourethral glands. Aggressive interactions between pigs were registered when a limited amount of feed was provided to the pigs prior to routine feeding. The number of initiated interactions (attacks) and the difference between number of initiated and received interactions (relative attacks) were calculated for each pig. Multivariate analysis revealed that gonadal hormones and reproductive organ size influenced prevalence of boar taint, accounting for 30% of the variation in skatole levels in fat and for 37% of the variation in androstenone levels in fat. These relations were independent of aggression levels in entire male pigs. Skatole levels were influenced by the levels of oestrone sulphate in plasma and free oestrone in fat, but not levels of plasma testosterone. Pigs with testes weight below 565 g and a bulbourethral gland length <90 mm did not produce high amounts of skatole; therefore, these values can be used as a threshold level to detect pig carcasses with low skatole levels. High androstenone levels could not be predicted by measuring reproductive organ sizes. More research is required to develop a rapid and accurate method for the analysis of carcasses of entire male pigs.
Development of Cat Embryos Produced by Intracytoplasmic Injection of Spermatozoa Stored in Alcohol
Authors: Murakami M , Karja NWK , Wongsrikeao P , Agung B , Taniguchi M , Naoi H , Otoi T 
Published: November 2005

ContentsThis study was conducted to examine whether cat spermatozoa stored in ethanol for 1 month was capable of developing into pronuclei and of supporting normal embryonic development. In vitro matured oocytes were injected with frozen–thawed spermatozoa and ethanol‐stored spermatozoa. The status of oocytes and sperm nuclei was examined at 4 and 18 h after injection of spermatozoa, and the presumptive zygotes were cultured for 7 days to assess the development of oocytes injected with each storage sperm. The percentage of enlarged sperm head at 4 h after injection was higher in ethanol‐stored spermatozoa than in frozen–thawed spermatozoa, but there was no significant difference in the development of oocytes and sperm nuclei at 18 h after injection between the two groups. The development of oocytes to the blastocyst stage after injection of spermatozoa was observed only in oocytes with frozen–thawed spermatozoa. Of oocytes injected with ethanol‐stored spermatozoa, two (2.8%) oocytes developed to the 16‐cell stage. These results indicate that cat spermatozoa stored in ethanol can decondense and form male pronuclei after intracytoplasmic injection. However, the oocytes injected with ethanol‐stored spermatozoa did not have the ability to develop to the blastocyst stage.