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1.
Food Chem ; 334: 127555, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711268

RESUMO

Conjugated linoleic acid (CLA) content of ruminant milk reported in published research papers (n = 65) from January 1995 to March 2020 around the world were analyzed to estimate the overall mean CLA value. The CLA content of ruminant milk samples was grouped according to geographical regions (Europe, South America, North America, Oceania, Asia, and Africa). The total CLA content of milk samples from cows, sheep, goats, yaks, and llama retrieved from the collected data ranged between 0.06 and 2.96% of total fatty acids. There is a wide variation of pooled estimated mean content of CLA in milk among the study regions and were highest in Oceania with 1.33% (95% confidence interval (CI): 1.16 - 1.49%) of total fatty acids. Though several factors have been reported to influence the CLA content of milk, the effect of the "geographical origin" was only considered in the present manuscript as one of the main factors in this respect.


Assuntos
Ácidos Linoleicos Conjugados/análise , Leite/química , África , Animais , Ásia , Bovinos , Europa (Continente) , Ácidos Graxos/análise , Cabras , América do Norte , Oceania , Ruminantes , Ovinos , América do Sul
2.
Vet Clin North Am Food Anim Pract ; 36(3): 509-524, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33032696

RESUMO

This article addresses diagnostic challenges involving toxicology cases that are multifactorial in nature, often involving sublethal exposures to multiple toxicants and/or other etiologies that are not toxic. Gold standard diagnostic approaches were developed under the assumption that cases were undoubtedly intoxications, and they still are applicable to those cases. A more integrated diagnostic approach, focusing on the initial problem list, is consistent with how veterinarians diagnose most cases. Livestock ownership attitudes continue to evolve. Ongoing threats to the financial well-being of animal agriculture ultimately will have an impact on the ability of producers to maintain health and performance of livestock.


Assuntos
Doenças dos Animais/induzido quimicamente , Xenobióticos/envenenamento , Animais , Bovinos , Gado , Ruminantes , Medicina Veterinária/métodos , Medicina Veterinária/normas
3.
Vet Clin North Am Food Anim Pract ; 36(3): 745-774, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33032704

RESUMO

This review focuses on factors associated with mold production in feedstuffs and major mycotoxins affecting ruminants in North America. Ruminants are often considered less sensitive to mycotoxins owing to rumen microflora metabolism to less toxic compounds. However, ruminants occupy wide agricultural niches that expose animals to diverse toxins under widely different environmental and nutritional conditions. Often the moldy and potentially highly contaminated feeds end up at feedlots. Less than optimal feedstuffs creating suboptimal rumen microbial flora could result in decreased ruminal capacity to detoxify certain mycotoxins and adverse effects. Numerous mycotoxins and clinical effects in ruminants are discussed.


Assuntos
Produtos Agrícolas/microbiologia , Micotoxicose/veterinária , Micotoxinas/envenenamento , Doenças das Plantas/microbiologia , Ruminantes , Ração Animal/análise , Ração Animal/microbiologia , Animais , Micotoxicose/metabolismo , América do Norte
4.
PLoS One ; 15(9): e0239478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986725

RESUMO

Rift Valley fever (RVF) is an arboviral zoonosis that primarily affects ruminants but can also cause illness in humans. The increasing impact of RVF in Africa and Middle East and the risk of expansion to other areas such as Europe, where competent mosquitos are already established, require the implementation of efficient surveillance programs in animal populations. For that, it is pivotal to regularly assess the performance of existing diagnostic tests and to evaluate the capacity of veterinary labs of endemic and non-endemic countries to detect the infection in an accurate and timely manner. In this context, the animal virology network of the MediLabSecure project organized between October 2016 and March 2017 an external quality assessment (EQA) to evaluate the RVF diagnostic capacities of beneficiary veterinary labs. This EQA was conceived as the last step of a training curriculum that included 2 diagnostic workshops that were organized by INIA-CISA (Spain) in 2015 and 2016. Seventeen veterinary diagnostic labs from 17 countries in the Mediterranean and Black Sea regions participated in this EQA. The exercise consisted of two panels of samples for molecular and serological detection of the virus. The laboratories were also provided with positive controls and all the kits and reagents necessary to perform the recommended diagnostic techniques. All the labs were able to apply the different protocols and to provide the results on time. The performance was good in the molecular panel with 70.6% of participants reporting 100% correct results, and excellent in the serological panel with 100% correct results reported by 94.1% of the labs. This EQA provided a good overview of the RVFV diagnostic capacities of the involved labs and demonstrated that most of them were able to correctly identify the virus genome and antibodies in different animal samples.


Assuntos
Febre do Vale de Rift/diagnóstico , Animais , Mar Negro , Culicidae , Europa (Continente) , Genoma Viral , Humanos , Laboratórios , Mar Mediterrâneo , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/genética , Ruminantes
5.
Vet Clin North Am Food Anim Pract ; 36(3): 775-789, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32943303

RESUMO

Selenium (Se) is a metalloid that exists as a red amorphous powder, reddish crystal, silver-gray crystal, or brown-black solid. Its potency as a nutrient and a toxicant is such that few people have seen the pure element. It is easy to lose sight of the narrow margin between too little and too much. The most common cause of selenosis is accidental or intentional overuse of supplements. Many target organs and effects of Se toxicity are similar to those of Se deficiency, so laboratory confirmation is necessary. Prevention consists of minimizing exposure to seleniferous feedstuffs and optimizing dietary factors that might aggravate selenosis.


Assuntos
Envenenamento/veterinária , Ruminantes , Selênio/envenenamento , Ração Animal/análise , Ração Animal/envenenamento , Animais , Suplementos Nutricionais/análise , Suplementos Nutricionais/envenenamento , Envenenamento/etiologia
6.
Vet Clin North Am Food Anim Pract ; 36(3): 525-546, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32943305

RESUMO

Determining mineral status of production animals is important when developing an optimum health program. Nutrition is the largest expense in food animal production and has the greatest impact on health and productivity of the animals. Knowing the bioavailability of minerals in the diet is difficult. Evaluating fluid or tissues from animals is the optimum method to determine bioavailability. Evaluating the diet provides some information. Serum/blood or liver from the animal needs to be analyzed to determine bioavailability of vitamin and minerals in the diet. This article reviews how to sample and the function of these minerals in cattle.


Assuntos
Gado/metabolismo , Minerais/metabolismo , Ruminantes/metabolismo , Animais , Dieta/veterinária , Gado/sangue , Minerais/análise , Estado Nutricional , Ruminantes/sangue , Vitaminas/sangue , Vitaminas/metabolismo
7.
Vet Clin North Am Food Anim Pract ; 36(3): 621-639, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32948410

RESUMO

Livestock can be exposed to a wide variety of commercial or industrial chemicals that have variable toxicity. Adverse effects can be due to acute or chronic illnesses and deaths or due to contamination of meat or milk intended for human consumption. A diagnosis can be challenging in the absence of a known exposure. It is critical that a complete evaluation be conducted and appropriate samples be collected for possible analysis. Appropriate experts and regulatory agencies should be consulted as soon as possible to avoid potential contaminated animal products reaching consumers.


Assuntos
Doenças dos Animais/induzido quimicamente , Poluentes Ambientais/envenenamento , Substâncias Perigosas/envenenamento , Agricultura , Doenças dos Animais/diagnóstico , Animais , Poluentes Ambientais/análise , Cabras , Substâncias Perigosas/análise , Humanos , Indústrias , Gado , Ruminantes , Ovinos
8.
Vet Clin North Am Food Anim Pract ; 36(3): 653-659, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32948412

RESUMO

Corn co-products are a co-product of the dry and wet corn-milling ethanol manufacturing industry. The dry mill corn co-product is distiller's grains. Distillers grain can be further categorized into dry distillers grains (DDG), DDG with solubles, wet distillers grains with solubles (WDGS), modified WDGS, and corn syrup (solubles). Wet mill ethanol production produces 2 main feed stuffs: corn gluten (wet and dry) and heavy steep water.


Assuntos
Biocombustíveis/envenenamento , Doenças dos Bovinos/induzido quimicamente , Encefalomalacia/veterinária , Ração Animal/análise , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Dieta/veterinária , Encefalomalacia/induzido quimicamente , Encefalomalacia/metabolismo , Sulfeto de Hidrogênio/metabolismo , Ruminantes , Zea mays/química
9.
Animal ; 14(S3): s453-s463, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32807248

RESUMO

Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3-) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change.


Assuntos
Gases de Efeito Estufa , Metano , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Leite , Poaceae , Rúmen , Ruminantes
10.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32766838

RESUMO

Traditional feed composition tables have been a useful tool in the field of animal nutrition throughout the last 70 yr. The objective of this paper is to discuss the challenges and opportunities associated with creating large feed ingredient composition tables. This manuscript will focus on three topics discussed during the National Animal Nutrition Program (NANP) Symposium in ruminant and nonruminant nutrition carried out at the American Society of Animal Science Annual Meeting in Austin, TX, on July 11, 2019, namely: 1) Using large datasets in feed composition tables and the importance of standard deviation in nutrient composition as well as different methods to obtain accurate standard deviation values, 2) Discussing the importance of fiber in animal nutrition and the evaluation of different methods to estimate fiber content of feeds, and 3) Description of novel feed sources, such as insects, algae, and single-cell protein, and challenges associated with the inclusion of such feeds in feed composition tables. Development of feed composition tables presents important challenges. For instance, large datasets provided by different sources tend to have errors and misclassifications. In addition, data are in different file formats, data structures, and feed classifications. Managing such large databases requires computers with high processing power and software that are also able to run automated procedures to consolidate files, to screen out outlying observations, and to detect misclassified records. Complex algorithms are necessary to identify misclassified samples and outliers aimed to obtain accurate nutrient composition values. Fiber is an important nutrient for both monogastrics and ruminants. Currently, there are several methods available to estimate the fiber content of feeds. However, many of them do not estimate fiber accurately. Total dietary fiber should be used as the standard method to estimate fiber concentrations in feeds. Finally, novel feed sources are a viable option to replace traditional feed sources from a nutritional perspective, but the large variation in nutrient composition among batches makes it difficult to provide reliable nutrient information to be tabulated. Further communication and cooperation among different stakeholders in the animal industry are required to produce reliable data on the nutrient composition to be published in feed composition tables.


Assuntos
Ração Animal/análise , Ração Animal/normas , Ruminantes/fisiologia , Sociedades Científicas/organização & administração , Sociedades Científicas/normas , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estados Unidos
11.
Chem Biol Interact ; 330: 109225, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795450

RESUMO

Two types of cholinesterases (ChEs) are present in mammalian blood and tissues: acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). While AChE regulates neurotransmission by hydrolyzing acetylcholine at the postsynaptic membranes and neuromuscular junctions, BChE in plasma has been suggested to be involved in detoxifying toxic compounds. This study was undertaken to establish the identity of circulating ChE activity in plasmas from domestic animals (bovine, ovine, caprine, porcine and equine) by assessing sensitivity to AChE-specific inhibitors (BW284c51 and edrophonium) and BChE-specific inhibitors (dibucaine, ethopropazine and Iso-OMPA) as well as binding to anti-FBS AChE monoclonal antibodies (MAbs). Based on the inhibition of ChE activity by ChE-specific inhibitors, it was determined that bovine, ovine and caprine plasma predominantly contain AChE, while porcine and equine plasma contain BChE. Three of the anti-FBS AChE MAbs, 4E5, 5E8 and 6H9, inhibited 85-98% of enzyme activity in bovine, ovine and caprine plasma, confirming that the esterase in these plasmas was AChE. These MAbs did not bind to purified recombinant human or mouse AChE, demonstrating that these MAbs were specific for AChEs from ruminant species. These MAbs did not inhibit the activity of purified human BChE, or ChE activity in porcine and equine plasma, confirming that the ChE in these plasmas was BChE. Taken together, these results demonstrate that anti-FBS AChE MAbs can serve as useful tools for distinguishing between AChEs from ruminant and non-ruminant species and BChEs.


Assuntos
Acetilcolinesterase/imunologia , Anticorpos Monoclonais/sangue , Butirilcolinesterase/imunologia , Acetilcolinesterase/sangue , Animais , Animais Domésticos/imunologia , Butirilcolinesterase/sangue , Bovinos , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Sangue Fetal/imunologia , Humanos , Camundongos , Ruminantes/imunologia
12.
Toxicon ; 187: 1-9, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798504

RESUMO

Enzootic calcinosis (EC), is a chronic disease, caused by toxic plants, which has mainly affected ruminants for more than 100 years. It is characterized by a soft tissue calcification, hypercalcemia, hyperphosphatemia, hypoparathiroidism, hypercalcitoninism, osteonecrosis, and osteopetrosis. The toxic compound reported in some of these plants are 1,25(OH)2D3 glycosides. Characterization of calcinogenic principles were performed with Solanum glaucophyllum, Trisetum flavescens, Cestrum diurnum, and Stenotaphrum secundatum. Other plant species involved in EC are: Nierembergia rivularis, Nierembergia veitchii, Solanum torvum, and Solanum stuckertii. Clinical and pathological findings are well characterized. We present different aspects of the pathogenic mechanism of EC, including genetic modulation, expression of bone proteins, cellular de-differentiation of arterial smooth muscle cells, phenotypic changes, production of a calcifiable matrix, and modulation of the calcium and phosphorus balance. The use of comparative pathology can bring significant advances in the understanding of the pathogenic mechanism. In this review we present a broad approach to the different aspects of intoxication: history of EC on different continents; plant species, distribution and morphology; toxic principle; pathogenesis; epidemiology; clinical signs; diagnosis; and control and prophylaxis.


Assuntos
Calcinose/veterinária , Intoxicação por Plantas , Plantas Tóxicas , Ruminantes/fisiologia , Animais
13.
PLoS One ; 15(7): e0235464, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32658938

RESUMO

Understanding locomotor activity patterns would reveal key information about an animal's foraging strategy, energy budget and evolutionary adaptation. We studied the locomotor activity patterns of the takin (Budorcas taxicolor) in a temperate mountain region in China using GPS radio-collar technology from 1 July 2014 to 30 June 2015. Our research showed that takin had a bimodal crepuscular locomotor activity pattern, with an especially obvious movement peak at dusk. The takins showed significant seasonal differences in their movement rates, with the lowest movement rate in winter. The animals also showed sexual differences in their movement rates. In spring, the female movement rate was significantly higher than that of males during daytime, while during nighttime the movement rate of males was higher than that of females. The male movement rate was significantly higher than that of females in summer. The movement rate of the takins were correlated to microenvironment temperature and normalized difference vegetation index (NDVI) in each season. These findings suggest that takin could adjust locomotor activity levels adapt to reproductive requirements, temperature variation and forage variability.


Assuntos
Locomoção/fisiologia , Reprodução/fisiologia , Ruminantes/fisiologia , Animais , China , Feminino , Sistemas de Informação Geográfica , Masculino , Filogenia , Estações do Ano
14.
PLoS One ; 15(7): e0236118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667943

RESUMO

The objective of this study was to evaluate whether pre-weaning heifer calves divergent for residual feed intake (RFI) or residual feed intake and body weight gain (RIG) exhibit differences in thermography, blood, and ruminal parameters. Thirty-two Gyr heifer calves were enrolled in a 63-d trial and classified into 2 feed efficiency (FE) groups based on RFI and RIG (mean ± 0.5 SD). The groups were classified as high efficiency (HE) RFI (HE RFI, n = 9), HE RIG (HE RIG, n = 10), low efficiency (LE) RFI (LE RFI, n = 10), and LE RIG (LE RIG, n = 11). The amount of whole milk provided for each calf was calculated based on their metabolic weight at birth (42% x BW0.75). The liquid diet was divided into two meals at 0700 and 1400 h. The total solid diet (TSD) was composed of 92% concentrate and 8% of Tifton 85 hay chopped in 5-cm lengths, as fed. Intake was measured daily. Blood concentrations of insulin, beta hydroxybutyrate, urea, and glucose, and ruminal pH, N-NH3, and volatile fatty acids (VFA) were evaluated at 14, 28, 42, 56, and 70 days of age. Thermal images of the calves were taken with an infrared camera (FLIR T420, FLIR Systems Inc., Wilsonville, OR) on d 56 (±3) at 0600 h, before the morning feeding. Total VFA concentration and propionate as % of total VFA were 24.2% and 22.2% lower in HE RFI compared to LE RFI calves, respectively. On the other hand, acetate as % of total VFA was 10.6% greater in HE RFI than LE RFI calves. Blood urea concentration tended to be greater in LE RFI than HE RFI calves. High efficiency HE RIG tended to have 6.8% greater acetate and 15.4% lower propionate as % of total VFA than LE RIG. Blood insulin concentration was greater and blood glucose tended to be greater for LE RIG than HE RIG group. Low efficiency RIG group had greater left rib, left flank, and anus surface temperature measured by infrared thermography than the HE RIG group. Differences in ruminal fermentation do not seem to be associated with pre-weaning calves efficiency, while differences in protein metabolism seem to affect RFI during this phase. Infrared thermography appears to be correlated to RIG in pre-weaning heifer calves.


Assuntos
Ração Animal/análise , Dieta/veterinária , Comportamento Alimentar/fisiologia , Termogênese , Desmame , Ganho de Peso , Animais , Células Sanguíneas/metabolismo , Bovinos , Ingestão de Energia , Ruminantes/metabolismo , Termografia
15.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 961-969, May-June, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129665

RESUMO

A total of 6593 weight records collected from 796 male and female Anglo-Nubian goats aged up to 130 days, offspring from 29 sires and 225 dams, were used to compare models and estimate genetic parameters throughout the growth curve by applying random regression models. Direct and maternal additive genetic effects and direct and maternal permanent environmental effects were included as random in the models. The contemporary groups were included as fixed effects and goat age at kidding was included as a covariable (linear and quadratic). The choice of the best model was based on the AIC, BIC and AICc criteria. Variance estimates of the four random effects increased as the animals aged. Direct heritability (h2) rose from 0.13 to 0.40 with age, whereas maternal heritability showed a low value. Genetic correlations of weight between closer ages were high. The most suitable random regression model to compare the fitting of random effects was that which employed the Legendre polynomials of quadratic order with homogeneous variance (3333-1).(AU)


Utilizaram-se 6593 pesos de 796 caprinos da raça Anglonubiana, coletados em machos e fêmeas com idade até 130 dias, descendentes de 29 reprodutores e 225 matrizes, com o objetivo de se compararem modelos e de se estimarem parâmetros genéticos ao longo da curva de crescimento com aplicação de modelos de regressão aleatória. Nos modelos, incluíram-se os efeitos genéticos aditivos diretos e maternos e os de ambiente permanente diretos e maternos como aleatórios; os grupos de contemporâneos foram incluídos como efeitos fixos, e a idade da cabra ao parto como covariável (linear e quadrática). A escolha do melhor modelo foi realizada pela avaliação dos critérios AIC, BIC e AICc. As estimativas de variâncias dos quatro efeitos aleatórios cresceram de acordo com o aumento da idade. A herdabilidade direta (h2) aumentou de 0,13 a 0,40 com a idade, e a materna apresentou baixo valor. As correlações genéticas do peso entre idades mais próximas foram altas. O modelo de regressão aleatório mais adequado ao se comparar o ajuste dos efeitos aleatórios foi o que empregou polinômios de Legendre de ordem quadrática com variância homogênea (3333-1).(AU)


Assuntos
Animais , Ruminantes/crescimento & desenvolvimento , Análise de Regressão , Perfil Genético , Hereditariedade , Correlação de Dados
16.
Animal ; 14(S3): s473-s483, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32580811

RESUMO

Over the last decade, extensive research effort has been placed on developing methane mitigation strategies in ruminants. Many disciplines on animal science disciplines have been involved, including nutrition and physiology, microbiology and genetic selection. To date, few of the suggested strategies have been implemented because: (1) methane emissions currently have no direct or indirect economic value for farmers, with no financial incentive to change practices and (2) most strategies have limited, or no, long-term effects. Consequently, there is a fundamental need for research on methane mitigation strategies across disciplines. Coordinated international initiatives similar to METHAGENE could represent highly relevant coordination tool of collaboration between countries, facilitating knowledge exchange, sharing concerns and building future collaborations.


Assuntos
Bovinos , Indústria de Laticínios , Metano , Ruminantes , Animais , Bovinos/genética , Genoma , Genômica , Seleção Genética
17.
PLoS One ; 15(6): e0234344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502191

RESUMO

Nitrogen (N) isotopic discrimination (i.e. the difference in natural 15N abundance between the animal proteins and the diet; Δ15N) is known to correlate with N use efficiency (NUE) and feed conversion efficiency (FCE) in ruminants. However, results from the literature are not always consistent across studies, likely due to isotopic discrimination pathways that may differ with the nature of diets. The objective of the present study was to assess at which level, from rumen to tissues, Δ15N originates and becomes related to NUE and FCE in fattening yearling bulls when they are fed two contrasted diets. Twenty-four Charolais yearling bulls were randomly divided into two groups and fed during 8 months, from weaning to slaughter, either 1) a high starch diet based on corn silage supplying a balanced N to energy ratio at the rumen level (starch) or 2) a high fiber diet based on grass silage supplying an excess of rumen degradable N (fiber). All animals were slaughtered and samples of different digestive pools (ruminal, duodenal, ileal and fecal contents), animal tissues (duodenum, liver and muscle), blood and urine were collected for each animal. Ruminal content was further used to isolate liquid-associated bacteria (LAB), protozoa and free ammonia, while plasma proteins were obtained from blood. All samples along with feed were analyzed for their N isotopic composition. For both diets, the digestive contribution (i.e. the N isotopic discrimination occurring before absorption) to the Δ15N observed in animal tissues accounted for 65 ± 11%, leaving only one third to the contribution of post-absorptive metabolism. Concerning the Δ15N in digestive pools, the majority of these changes occurred in the rumen (av. Δ15N = 2.12 ± 0.66‰), with only minor 15N enrichments thereafter (av. Δ15N = 2.24 ± 0.41‰), highlighting the key role of the rumen on N isotopic discrimination. A strong, significant overall relationship (n = 24) between Δ15N and FCE or NUE was found when using any post-absorptive metabolic pool (duodenum, liver, or muscle tissues, or plasma proteins; 0.52 < r < 0.73; P ≤ 0.01), probably as these pools reflect both digestive and post-absorptive metabolic phenomena. Fiber diet compared to starch diet had a lower feed efficiency and promoted higher (P ≤ 0.05) Δ15N values across all post-absorptive metabolic pools and some digestive pools (ruminal, duodenal, and ileal contents). The within-diet relationship (n = 12) between Δ15N and feed efficiency was not as strong and consistent as the overall relationship, with contrasted responses between the two diets for specific pools (diet x pool interaction; P ≤ 0.01). Our results highlight the contrasted use of N at the rumen level between the two experimental diets and suggests the need for different equations to predict FCE or NUE from Δ15N according to the type of diet. In conclusion, rumen digestion and associated microbial activity can play an important role on N isotopic discrimination so rumen effect related to diet may interfere with the relationship between Δ15N and feed efficiency in fattening yearling bulls.


Assuntos
Ração Animal/análise , Dieta/métodos , Nitrogênio/metabolismo , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Bovinos , Carboidratos da Dieta/metabolismo , Fibras na Dieta/metabolismo , Digestão/fisiologia , Fezes/química , Masculino , Rúmen/microbiologia , Ruminantes/metabolismo , Amido/metabolismo
18.
PLoS One ; 15(6): e0234064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497115

RESUMO

Captive breeding programs for endangered species can increase population numbers for eventual reintroduction to the wild. Captive populations are typically small and isolated, which results in inbreeding and reduction of genetic variability, and may lead to an increased risk of extinction. The Omkoi Wildlife Breeding Center maintains the only Thai captive Chinese goral (Naemorhedus griseus) population, and has plans to reintroduce individuals into natural isolated populations. Genetic variability was assessed within the captive population using microsatellite data. Although no bottleneck was observed, genetic variability was low (allelic richness = 7.091 ± 0.756, He = 0.455 ± 0.219; He < Ho) and 11 microsatellite loci were informative that likely reflect inbreeding. Estimates of small effective population size and limited numbers of founders, combined with wild-born individuals within subpopulations, tend to cause reduction of genetic variability over time in captive programs. This leads to low reproductive fitness and limited ability to adapt to environmental change, thereby increasing the risk of extinction. Management of captive populations as evolutionarily significant units with diverse genetic backgrounds offers an effective strategy for population recovery. Relocation of individuals among subpopulations, or introduction of newly captured wild individuals into the captive program will help to ensure the future security of Chinese goral. Implications for future conservation actions for the species are discussed herein.


Assuntos
Conservação dos Recursos Naturais , Ruminantes/genética , Animais , Cruzamento , Extinção Biológica , Feminino , Variação Genética , Funções Verossimilhança , Masculino , Dinâmica Populacional , Tailândia
19.
J Zoo Wildl Med ; 51(2): 321-325, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549561

RESUMO

Pronghorn (Antilocapra americana) are native to western North America and are found in 24 Association of Zoos and Aquariums (AZA)-accredited institutions. Acute-phase proteins (APP) are a broad class of proteins that are stimulated in response to inflammation and have been shown to be a sensitive measure of inflammation in equids and ruminants. In this study, blood samples from clinically normal free-ranging and captive populations of pronghorn were analyzed using assays for protein electrophoresis (EPH) and APP, including serum amyloid A (SAA) and haptoglobin (HP), to develop preliminary ranges to gauge potential differences between these populations. Additional samples were taken from clinically abnormal captive pronghorn with facial abscesses. By EPH measurements, albumin: globulin ratio mean and SE were significantly different (P <0.05) with 1.02 (0.08) for captive populations and 1.91 (0.05) for free-ranging populations. Total protein mean and SE were significantly different (P <0.05) for captive and free-ranging populations, respectively 5.6 (0.3) g/dl and 6.9 (0.1) g/dl. Mean and SD of SAA for captive pronghorn were 1.4 (3.2) mg/L, and were significantly different from the free-ranging population, which was below the limits of detection for (P <0.05). There was no difference in HP levels between these groups. In a case study of a pronghorn with facial abscesses, elevated levels of HP, but not SAA, suggested that HP maybe useful in certain disease states. Future studies should explore the use of these biomarkers as tools to monitor general health, prognosis, and subclinical disease.


Assuntos
Proteínas da Fase Aguda/metabolismo , Animais Selvagens/sangue , Animais de Zoológico/sangue , Eletroforese das Proteínas Sanguíneas/veterinária , Ruminantes/sangue , Animais , Feminino , Masculino , América do Norte , Valores de Referência , Texas
20.
PLoS One ; 15(6): e0234126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502162

RESUMO

Different techniques have been applied in feed processing to improve ruminal degradation and nutrient utilization in ruminant. There are limited studies investigating how moist heating process impacts barley protein utilization and internal molecular structures. The objectives of this study were to investigate: 1) how moist heating affects barley protein chemical profiles and Cornell Net Carbohydrate and Protein System (CNCPS) subfractions, in situ rumen degradation parameters, and predicted intestinal protein supply and feed milk value; 2) how moist heating affects protein molecular spectral features; and 3) the relationship between protein molecular structure spectral features and protein chemical profiles and metabolic characteristics. The barley variety CDC cowboy samples collected from the research farm during two consecutive years were used. Half of each sample was kept as raw and the other half underwent moist heating. The advanced molecular spectroscopy (attenuated total reflectance-fourier transform infrared, ATR-FTIR) was used to detect the barley protein molecular structure spectral features. It was found that moist heating decreased the fractions of soluble protein and increased the moderately degradable protein and ingestible protein fractions. This further resulted in the changes of in situ rumen degradation parameters and intestinal protein digestion characteristics. The protein molecular structure spectral features detected by using ATR-FTIR spectroscopy can be used as potential predictors for protein related chemical and metabolic parameters.


Assuntos
Hordeum/metabolismo , Proteínas de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Digestão , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Estrutura Secundária de Proteína , Rúmen/metabolismo , Ruminantes , Temperatura
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