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1.
Transl Anim Sci ; 7(1): txac167, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36915384

RESUMO

There were 463,000 head of beef cows in New Mexico as of January 1, 2021 (NASS, 2020), down roughly 4% from 2020 (NASS, 2019). Frequent drought often results in herd reduction and loss of valuable genetic progress. Bull selection is critical due to their influence on herd development. A survey was conducted to identify traits important to bull selection in New Mexico. Surveys were collected digitally (n = 83) and via the mail (n = 74). Responses were largely by cow/calf producers averaging 57 ± 1 years old with 24 ± 1 years' experience. Survey respondents represented 4,384,296 acres of private owned, private leased, and leased public rangeland and irrigated pasture meadow in New Mexico and surrounding states. Average cow/calf operation size was 294 ± 39 head and average bull herd size was 21 ± 3 head. Average price paid for a bull in the past 2 years was $3,981 ± 213. Physical characteristics, individual bull performance information, and genetic information are all important traits to New Mexico bull buyers; however, most producers (56%) indicated that structural soundness was the most important factor influencing their selection decisions. Amongst expected progeny differences (EPDs), New Mexico producers consider the calving ease direct (CED) and birth weight (BW) EPDS to be most important (40% and 35%, respectively). Producers also indicated that multitrait selection indexes used by the American Angus Association were important to their selection decisions, with the beef value ($B) and weaned calf value ($W) indexes being cited most often (35% and 31%, respectively). Elements important to bull purchase include the bull's sale preview (87%), body condition score (86%), feed efficiency/average daily gain information (85%), and actual scrotal circumference (82%). Following purchase of a new bull, most (60%) keep the bull separate from the cow herd until the following breeding season, while the remaining 40% of producers turn newly purchased bulls out within 30 days of purchase. Sixty eight percent of producers evaluate semen quality annually or prior to the start of the breeding season. Interestingly, 39% of producers indicated they used reproductive technologies like artificial insemination and synchronization of estrus while most (80%) test for trichomoniasis. The primary factor influencing culling decisions is age, followed by soundness and fertility.

2.
Phytochem Anal ; 20(5): 378-84, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19533596

RESUMO

INTRODUCTION: Plant volatiles (PVOCs) are important targets for studies in natural products, chemotaxonomy and biochemical ecology. The complexity of PVOC profiles often limits research to studies targeting only easily identified compounds. With the availability of mass spectral libraries and recent growth of retention index (RI) libraries, PVOC identification can be achieved using only gas chromatography coupled to mass spectrometry (GCMS). However, RI library searching is not typically automated, and until recently, RI libraries were both limited in scope and costly to obtain. OBJECTIVE: To automate RI calculation and lookup functions commonly utilised in PVOC analysis. METHODOLOGY: Formulae required for calculating retention indices from retention time data were placed in a spreadsheet along with lookup functions and a retention index library. Retention times obtained from GCMS analysis of alkane standards and Koeberlinia spinosa essential oil were entered into the spreadsheet to determine retention indices. Indices were used in combination with mass spectral analysis to identify compounds contained in Koeberlinia spinosa essential oil. RESULTS: Eighteen compounds were positively identified. Total oil yield was low, with only 5 ppm in purple berries. The most abundant compounds were octen-3-ol and methyl salicylate. The spreadsheet accurately calculated RIs of the detected compounds. CONCLUSION: The downloadable spreadsheet tool developed for this study provides a calculator and RI library that works in conjuction with GCMS or other analytical techniques to identify PVOCs in plant extracts.


Assuntos
Algoritmos , Magnoliopsida/química , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Magnoliopsida/crescimento & desenvolvimento , Espectrometria de Massas , New Mexico , Óleos Voláteis/análise , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Óleos de Plantas/análise , Óleos de Plantas/isolamento & purificação , Reprodutibilidade dos Testes , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Appl Spectrosc ; 60(7): 800-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16854269

RESUMO

Photoluminescence of plant extract solutions has been investigated for discrimination of plant life forms (grasses, forbs, and shrubs) using principal component analysis (PCA). Clippings from each of six plant species representing three different plant life forms potentially found in the diets of free-ranging herbivores in the Chihuahuan Desert of North America were investigated for possible discernment. These plants included Sporobolus flexuosus (mesa dropseed, a grass), Pleuraphis mutica (tobosa, a grass), Dimorphocarpa wislizenii (spectacle pod, a forb), Sphaeralcea incana (pale globemallow, a forb), Flourensia cernua leaves (tarbush, a shrub), and Atriplex canescens leaves and stems (fourwing saltbush, a shrub). Emission spectra (370-600 nm) from phosphate buffered saline (PBS) extract solutions (pH 2.2, 7.5 and 12.5) were recorded for each plant with excitation at 365 nm. Use of PBS minimized chlorophyll interference. Discernment among plant life forms within these plant species was achieved.


Assuntos
Ração Animal , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Poaceae/química , Cloreto de Sódio , Animais , Animais Selvagens , Soluções Tampão , Clima Desértico , Luminescência , Fosfatos , Folhas de Planta/química , Solventes
4.
J Agric Food Chem ; 53(22): 8694-8, 2005 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-16248573

RESUMO

Isolation and characterization of leaf volatiles in Anemopsis californica (Nutt.) Hook. and Arn. (A. californica) was performed using steam distillation, solid-phase microextraction, and supercritical fluid extraction. Thirty-eight compounds were detected and identified by gas chromatography; elemicin was the major component of the leaf volatiles. While the composition of the leaf volatiles varied with method of extraction, alpha-pinene, sabinene, beta-phellandrene, 1,8-cineole, piperitone, methyl eugenol, (E)-caryophyllene, and elemicin were usually present in readily detectable amounts. Greenhouse-reared clones of a wild population of A. californica had an identical leaf volatile composition with the parent plants. Steam-distilled oil had antimicrobial properties against 3 (Staphylococcus aureus, Streptococcus pneumoniae, and Geotrichim candidum) of 11 microbial species tested. Some of this bioactivity could be accounted for by the alpha-pinene in the oil.


Assuntos
Anti-Infecciosos/análise , Magnoliopsida/química , Folhas de Planta/química , Óleos de Plantas/química , Anti-Infecciosos/farmacologia , Monoterpenos Bicíclicos , Eugenol/análogos & derivados , Eugenol/análise , Geotrichum/efeitos dos fármacos , Monoterpenos/análise , Monoterpenos/farmacologia , Pirogalol/análogos & derivados , Pirogalol/análise , Pirogalol/síntese química , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Volatilização
5.
Talanta ; 59(3): 601-4, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18968945

RESUMO

Fluorescent contaminants have been observed when stock solutions of phosphate buffered saline solutions at each of three pH values (2.2, 7.5, and 12.5) are analyzed after passing through commercially available filter paper. The filtrate's fluorescence was observed to exhibit a maximum signal at 440.0 nm when excited at 365 nm. Detection of trace components could have significant implications in the design and implementation of sample processing protocols when using fluorescence.

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