Influence of nutrition and body condition on pituitary, ovarian, and thyroid function of nonlactating beef cows     

R J Rasby  R P Wettemann  R D Geisert  J J Wagner  K S Lusby 《Journal of animal science》1991,69(5):2073-2080

Nonpregnant Hereford cows (n = 70) were used to determine the effect of nutrient intake and body condition on reproductive and thyroid function. Body condition scores (BCS; 1 = emaciated; 9 = obese) of cows averaged 5.0 +/- .2 on July 1, and cows were fed for 4 mo either to lose weight and BCS (thin; n = 22), to maintain weight and BCS (moderate; n = 24), or to gain weight and BCS (fat; n = 24). After November 1, cows received a complete ration to maintain weight and BCS. Cows were slaughtered in December (six thin, eight moderate, and eight fat cows) or the subsequent March (16 cows per group). Before slaughter, cows were given two injections of prostaglandin F2 alpha (PGF) 11 d apart. Six days after the second PGF injection, cows were simultaneously treated with 100 micrograms of gonadotropin releasing hormone (GnRH; i.m.) and 100 micrograms of thyrotropin releasing hormone (TRH; i.v.) and serum samples were obtained. The BCS of cows at slaughter (8 d after PGF) averaged 3.4, 5.3, and 7.1 (P less than .01) and carcass energy content averaged 243, 432, and 714 Mcal (P less than .01) for thin, moderate, and fat cows, respectively. Wet ovarian (P less than .001) and corpora lutea (P less than .01) weights were heavier for fat cows. Content of LH in the pituitary gland and concentrations of thyroxine (T4) in serum after GnRH/TRH were not influenced by nutrient intake or BCS. However, thin cows had greater concentrations (P less than .05) of LH in serum after GnRH/TRH than did moderate or fat cows. We conclude that nutrient intake and body energy reserves of beef cows influenced ovarian function and LH in serum after treatment with GnRH.  相似文献   

Technical note: a double L intestinal cannula for cattle   总被引：1，自引：0，他引：1  

M N Streeter  S J Barron  D G Wagner  C A Hibberd  F N Owens  F T McCollum 《Journal of animal science》1991,69(6):2601-2607

A double L-shaped intestinal cannula was developed in an attempt to overcome problems observed previously with simple T-type cannulas. The cannula was constructed from cyclopolyvinyl chloride water pipe fittings. Construction materials were fairly rigid, but by connecting the split cannula pieces with elastic castration bands the cannula had some flexibility. Placing a short cone over the exposed cannula barrel reduced mechanical damage to the intestine. The double L cannula required a much smaller incision in the intestine during surgical insertion than a T-type cannula; it also simplified replacement. Construction is described; use and performance of the cannula has been satisfactory.  相似文献   

Die Ertragsbildung und Ertragsstruktur eines konventionellen und eines epigonalen Genotyps der Weißen Lupine (Lupinus albus)     

H. Stützel    W. Aufhammer    A. Rautenkranz    B. Wagner    J. Falfus  E. Nalborczyk 《Journal of Agronomy and Crop Science》1993,170(3):177-186

Yield formation and yield components of a conventional and an epigonal genotype of white lupin ( Lupinus albus )
Differences in yield formation and yield structure of two contrasting Lupinus albus growth types, the conventional, freely branching cultivar Kalina and the epigonal. little branching cultivar Ep I were analyzed. Both cultivars were grown in field experiments at Hohenheim in 1987 and 1988 with a combined variation of population density (30–120 plants/m²) and plant distribution. In addition, assimilate distribution within the plant was studied using a ¹⁴C-labelling experiment. – The contributions of branches to light interception of the crops during the generative phase were > 90 % in Kalina as compared to about 30 % in Ep 1 . Relative ¹⁴C uptake of branches was in a similar range, but great proportions of the ¹⁴C taken up by branches was translocated to main stems. No genotype x plant density interactions with respect to grain yield were recorded, indicating that yield formation at main stems and branches was affected by cropping conditions similarly in both genotypes. This applies to the conditions of the experiments, where stress effects were absent. Under these conditions, the conventional genotype showed agronomic, but no physiological disadvantages.  相似文献   

Epidural abscess and discospondylitis in a dog after administration of a lumbosacral epidural analgesic.          下载免费PDF全文

A M Remedios  R Wagner  N A Caulkett    T Duke 《The Canadian veterinary journal. La revue veterinaire canadienne》1996,37(2):106-107

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Bark beetle community structure under four ponderosa pine forest stand conditions in northern Arizona     

Guillermo S  nchez-Martí  nez  Michael R. Wagner 《Forest Ecology and Management》2002,170(1-3):145-160

We studied the bark beetle guild (Coleoptera: Scolytidae) in the ponderosa pine forests of northern Arizona to explore if the species assemblages and relative abundance differ between managed and unmanaged stands. Four stand conditions were assessed: (1) unmanaged stands with high tree density, (2) thinned stands, (3) thinned and burned (with prescribed fire) stands and (4) stands that had been burned by stand replacing wildfires. The study was conducted in the ponderosa pine forests of the Coconino Plateau, northern Arizona. For several decades this area has been relatively free of bark beetle outbreaks despite the current overstocked condition of many stands. We found that a similar species assemblage composed of Dendroctonus frontalis, D. brevicomis, D. valens, D. approximatus, D. ponderosae, and Ips pini occurred across all four stand conditions over 3 years of study. The population levels of all these species were endemic across all stand conditions. The non-aggressive D. approximatus and D. valens were indicator species for thinned and unmanaged stands, respectively, but this was not consistent among years. The ambrosia beetle Gnathotrichus sp. and the bark beetle predator Enoclerus sp. consistently indicated stands burned by wildfire. In addition to our field experiment, we analyzed the historical pattern of attacks of bark beetles in our area of study. Our findings suggest that the pattern of attack of D. brevicomis (the only Dendroctonus species for which attacks have been reported) and Ips spp. has been through scattered small infestations in groups of 1–10 trees. Whereas small infestations by Ips spp. are increasing, those for D. brevicomis are decreasing. Although we agree that the high density stands in northern Arizona are in an “unhealthy” condition, our results do not show that they were supporting large bark beetle outbreaks. Our results challenge the theoretical assumptions about the relationship between stand structure, tree resistance and bark beetle performance.  相似文献   

A serological survey for anaplasmosis in cattle in the Mexican states of Nuevo Leon,Tamaulipas and Coahuila using the card test     

R.F. Teclaw  S. Romo  Z. Garcia  G.G. Wagner 《Preventive veterinary medicine》1985,3(5):417-425

Blood samples from 2156 cattle from 40 herds in the Mexican states of Nuevo Leon, Tamaulipas and Coahuila were tested for antibody activity to Anaplasma marginale using the card test. Herd prevalence rates ranged from 0 to 86% with a mean of 22%. Analysis of joint positivity to A. marginale and Babesia bovis and to A. marginale and B. bigemina in individual animals resulted in the rejection of the null hypothesis of no association in 7 and 8 of 37 herds, respectively.  相似文献   

Bestimmung einiger Parameter des kapillaren Feuchtigkeitstransports in porösen Baustoffen. Teil 1: Herleitung der Stoffparameter     

Armin Wagner  Konrad Niesel  Christian Kowalec 《植物养料与土壤学杂志》1995,158(4):375-377

Determining some parameters of capillary moisture transport in porous building materials. Part 1: Deriving the material parameters Various relevant material parameters were defined and their mutual correlations pointed out. By means of simple mathematical approaches, one can calculate several characteristic data such as e.g. water absorption and water penetration coefficients, water capacity, capillary rise maximum, velocity of the rising liquid front and post-suction time.  相似文献   

Der Einfluß von 3,4 Benzfluoranthen auf die vegetativen und generativen Organe von Sommerweizen und Sommerroggen     

K. H. Wagner  S. Akbari  E. Wagner-Hering 《植物养料与土壤学杂志》1970,127(3):233-242

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Studies on the constituents of a Brazilian folk infusion. Isolation and structure elucidation of new triterpene saponins from Ilex amara leaves.     

Fabio Donisete Pezzuto de Andrade  Sonia Piacente  Cosimo Pizza  Wagner Vilegas 《Journal of agricultural and food chemistry》2002,50(2):255-261

The isolation of three new triterpene saponins 3beta-O-beta-D-glucopyranosyl-(1-->3)-alpha-L-2-O-acetylarabinopyranosylolean-12-en-28-oic acid 28-O-beta-D-glucopyranosyl ester (2), 3beta-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-O-arabinopyranosylurs-12-en-28-oic acid (3), and 3beta-O-beta-D-glucopyranosyl-(1-->2)-beta-D-O-galactopyranosylurs-12-en-28-oic acid (4) together with five known saponins and one flavonoid glycoside from the aqueous infusion of Ilex amara (Vellozo) Loes. leaves is reported. All structures were elucidated by spectroscopic methods, including the concerted application of one-dimensional (1H, TOCSY, 13C, and 13C DEPT NMR) and two-dimensional NMR techniques (DQF-COSY, HSQC, and HMBC).  相似文献   

First decadal response to treatment in a disturbance-based silviculture experiment in Maine     

Justin E. ArseneaultMike R. Saunders  Robert S. SeymourRobert G. Wagner 《Forest Ecology and Management》2011,262(3):404-412

Disturbance-based silvicultural systems generally seek to promote complex stand structures that are consistent with temporal and spatial patterns of natural disturbance while allowing for the sustainable harvest of timber. Gap-based harvesting systems are commonly used within this framework because they can be designed to approximate the frequencies and spatial patterns of a wide array of disturbance regimes. Patterns in stand-level growth, sapling recruitment and regeneration response were examined for one such gap-based system, the Acadian Forest Ecosystem Research Program (AFERP) in central Maine, that was designed to emulate the annual 1% disturbance frequency typical of the northeastern United States and Canada. A decade after treatment, stand-level differences in basal area growth and density between two gap-based treatments and an unharvested control were not statistically significant, largely due to low replication, but within-stand growth and regeneration responses differed strongly by spatial position relative to harvest gaps. Regeneration of shade-tolerant and intolerant species increased regardless of gap size, likely a response to increasing light availability from canopy openings due to harvesting and mortality. Further, there was evidence of gap size effects on sapling recruitment as large gaps (>1000 m²) favored the growth and survival of mid-successional species such as red maple and white pine, while small gaps (<1000 m²) favored late-succession species such as eastern hemlock and spruce. Overstory growth rates also differed by both species and position relative to harvest gaps with most species growing best in gaps and better along gap edges than in adjacent forest. Notably, overstory growth rates for white pine were not influenced by spatial position. These results suggest harvest gaps may have significant growth and regeneration impacts in adjacent, yet unharvested areas, which could lead to profound differences in forest development over the rotation. Obviously, longer-term studies of gap-based systems are needed to more clearly elucidate these responses.  相似文献