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1.
J Anim Sci ; 100(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35772753

RESUMO

The corpus luteum (CL) forms following ovulation from the remnant of the Graafian follicle. This transient tissue produces critical hormones to maintain pregnancy, including the steroid progesterone. In cattle and other ruminants, the presence of an embryo determines if the lifespan of the CL will be prolonged to ensure successful implantation and gestation, or if the tissue will undergo destruction in the process known as luteolysis. Infertility and subfertility in dairy and beef cattle results in substantial economic loss to producers each year. In addition, this has the potential to exacerbate climate change because more animals are needed to produce high-quality protein to feed the growing world population. Successful pregnancies require coordinated regulation of uterine and ovarian function by the developing embryo. These processes are often collectively termed "maternal recognition of pregnancy." Research into the formation, function, and destruction of the bovine CL by the Northeast Multistate Project, one of the oldest continuously funded Hatch projects by the USDA, has produced a large body of evidence increasing our knowledge of the contribution of ovarian processes to fertility in ruminants. This review presents some of the seminal research into the regulation of the ruminant CL, as well as identifying mechanisms that remain to be completely validated in the bovine CL. This review also contains a broad discussion of the roles of prostaglandins, immune cells, as well as mechanisms contributing to steroidogenesis in the ruminant CL. A triadic model of luteolysis is discussed wherein the interactions among immune cells, endothelial cells, and luteal cells dictate the ability of the ruminant CL to respond to a luteolytic stimulus, along with other novel hypotheses for future research.


The corpus luteum (CL) forms on the ovary from the cellular remnants of the follicle following ovulation. The function of the CL is to produce progesterone that is required for successful pregnancy. In the absence of an embryo or sufficient embryonic signaling, the uterus will release a prostaglandin that kills the CL in a process called luteolysis. Therefore, the CL and the embryo share a symbiotic relationship, each requiring the other to be healthy and functional for survival. The Northeast Multistate Project, one of the oldest in the nation, has produced a large body of evidence that has enhanced our understanding of how the CL functions, its regulation, and the impact of ovarian activity on fertility of cattle. This review highlights some of the important advances made in the understanding of the ruminant CL.


Assuntos
Corpo Lúteo , Células Endoteliais , Animais , Bovinos , Corpo Lúteo/fisiologia , Feminino , Luteólise , Gravidez , Progesterona/metabolismo , Ruminantes/fisiologia
2.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 853-860, Jul.-Aug. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285259

RESUMO

The objective of this work was to evaluate the biochemical and hormonal variables of Moxotó and Canindé goats submitted to two temperatures - 26.0±0.6 (thermoneutral) and 32.0±1.2°C (above thermal comfort zone) - and consuming water with three levels of salinity (1.0, 6.0 and 12.0 dSm-1). Thirty-six animals (18 of each breed) were used, with an average age of 5.0±0.6months and an average weight of 20.0±2.3kg, housed in metabolic cages inside a climate chamber. The animals were distributed in a completely randomized design with a 2 × 2 × 3 factorial scheme (2 breeds, 2 temperatures and 3 levels of salinity) and three replications. The glucose and urea had a significant effect (P>0.05) according to water salinity. Glucose, cholesterol, protein, albumin, globulin, aspartate aminotransferase and hormones (T4, T3 and cortisol) varied according to temperature (P<0.05). There was a significant effect of time on hormonal variables (P<0.05). Biochemical and hormonal variables changed according to temperature and day shift, so that metabolism was reduced in the animals under thermal stress and accelerated when animals were in the thermal comfort zone.(AU)


O objetivo do trabalho foi avaliar as variáveis bioquímicas e hormonais de caprinos das raças Moxotó e Canindé, submetidos a duas temperaturas (26,0±0,6ºC e 32,0±1,2ºC), termoneutra e acima da zona de conforto térmico, respectivamente), consumindo água com três níveis de salinidade (1,0, 6,0 e 12,0dSm-1), utilizando-se 36 animais (18 de cada raça), com idade média de 5,0±0,6 meses e peso médio de 20,0±2,3kg, alojados em gaiolas metabólicas no interior de uma câmara climática. Os animais foram distribuídos em um delineamento inteiramente ao acaso, com esquema fatorial de 2 x 2 x 3 (2 raças, 2 temperaturas e 3 níveis de salinidade) e três repetições. A glicose e a ureia apresentaram efeito significativo (P<0,05) em função da salinidade da água. Glicose, colesterol, proteína, albumina, globulina, AST e hormônios (T4, T3 e cortisol) variaram conforme as temperaturas (P<0,05). Observou-se efeito significativo do horário sobre as variáveis hormonais (P<0,05). As variáveis bioquímicas e hormonais sofrem alterações em função da temperatura e do turno do dia, de modo que o metabolismo é reduzido em animais sob estresse térmico e acelerado quando os animais encontram-se na zona de conforto térmico.(AU)


Assuntos
Animais , Fenômenos Fisiológicos Sanguíneos , Ruminantes/fisiologia , Águas Salinas/análise , Salinidade , Hormônios
3.
Cells ; 10(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947050

RESUMO

In polyandrous species, males face reproductive competition both before and after mating. Sexual selection thus shapes the evolution of both pre- and postcopulatory traits, creating competing demands on resource allocation to different reproductive episodes. Traits subject to strong selection exhibit accelerated rates of phenotypic divergence, and examining evolutionary rates may inform us about the relative importance and potential fitness consequences of investing in traits under either pre- or postcopulatory sexual selection. Here, we used a comparative approach to assess evolutionary rates of key competitive traits in two artiodactyl families, bovids (family Bovidae) and cervids (family Cervidae), where male-male competition can occur before and after mating. We quantified and compared evolutionary rates of male weaponry (horns and antlers), body size/mass, testes mass, and sperm morphometrics. We found that weapons evolve faster than sperm dimensions. In contrast, testes and body mass evolve at similar rates. These results suggest strong, but differential, selection on both pre- and postcopulatory traits in bovids and cervids. Furthermore, we documented distinct evolutionary rates among different sperm components, with sperm head and midpiece evolving faster than the flagellum. Finally, we demonstrate that, despite considerable differences in weapon development between bovids and cervids, the overall evolutionary patterns between these families were broadly consistent.


Assuntos
Evolução Molecular , Preferência de Acasalamento Animal , Ruminantes/genética , Animais , Chifres de Veado/anatomia & histologia , Tamanho Corporal , Masculino , Ruminantes/fisiologia , Espermatozoides/citologia , Testículo/anatomia & histologia
4.
Nat Rev Microbiol ; 19(9): 553-566, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33981031

RESUMO

Ruminants produce edible products and contribute to food security. They house a complex rumen microbial community that enables the host to digest their plant feed through microbial-mediated fermentation. However, the rumen microbiome is also responsible for the production of one of the most potent greenhouse gases, methane, and contributes about 18% of its total anthropogenic emissions. Conventional methods to lower methane production by ruminants have proved successful, but to a limited and often temporary extent. An increased understanding of the host-microbiome interactions has led to the development of new mitigation strategies. In this Review we describe the composition, ecology and metabolism of the rumen microbiome, and the impact on host physiology and the environment. We also discuss the most pertinent methane mitigation strategies that emerged to balance food security and environmental impacts.


Assuntos
Bactérias/classificação , Meio Ambiente , Segurança Alimentar , Microbioma Gastrointestinal/fisiologia , Rúmen/microbiologia , Ruminantes/microbiologia , Animais , Bactérias/metabolismo , Ruminantes/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-33794366

RESUMO

Rumen content stratification and the degree of dissociation of particle and fluid retention in the reticulorumen differ between 'moose-type' and 'cattle-type' ruminant species. These differences are not strictly linked to diet, except for a seeming limitation of 'moose-type' ruminants to a browsing niche. Nevertheless, these differences can be plausibly linked to other observed differences in ruminants, such as the intraruminal papillation pattern, or the size of the omasum. However, many of the corresponding measures are still only available for a restricted number of species. Here, we investigated the dry matter (i.e., the inverse of the moisture) concentration in forestomach contents of 10 blackbuck (Antilope cervicapra) and 7 Arabian sand gazelle (Gazella subgutturosa marica), and quantified the rumen papillation pattern. The blackbucks had distinct rumen contents stratification, with more moisture in ventral than in dorsal contents (difference 3.6% units, P < 0.001), whereas this difference was much less pronounced in the sand gazelles (0.6% units, P = 0.227). While reticulum contents were particularly moist in both species, omasum contents were particularly dry in sand gazelles, but did not differ in moisture from rumen contents in the blackbuck. This species is an outlier among ruminants due to its extremely small omasum. The intraruminal papillation pattern did not differ between blackbucks and sand gazelles and showed a surface enlargement factor (SEF) in the dorsal rumen of 27-28% of the SEF in the Atrium ruminis. Compared to data on digesta retention in the same species, the findings are in line with the overall concept of a high fluid throughput causing a distinct stratification of rumen contents and intraruminal papillation, and necessitating a large omasum for fluid re-absorption. However, the data also show that individual species may not correspond to all the assumptions of the concept, suggesting taxon-specific differences between species. Reasons for these differences cannot be linked to a dietary grass-browse spectrum, but may lie in evolutionary contingency.


Assuntos
Antílopes/fisiologia , Cervos/fisiologia , Estômago/metabolismo , Ração Animal , Animais , Bovinos , Dieta , Feminino , Trato Gastrointestinal/fisiologia , Masculino , Filogenia , Rúmen/metabolismo , Rúmen/fisiologia , Ruminantes/fisiologia , Especificidade da Espécie
6.
Genes (Basel) ; 12(4)2021 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916721

RESUMO

In mammals, milk is essential for the growth, development, and health. Milk quantity and quality are dependent on mammary development, strongly influenced by nutrition. This review provides an overview of the data on nutritional regulations of mammary development and gene expression involved in milk component synthesis. Mammary development is described related to rodents, rabbits, and pigs, common models in mammary biology. Molecular mechanisms of the nutritional regulation of milk synthesis are reported in ruminants regarding the importance of ruminant milk in human health. The effects of dietary quantitative and qualitative alterations are described considering the dietary composition and in regard to the periods of nutritional susceptibly. During lactation, the effects of lipid supplementation and feed restriction or deprivation are discussed regarding gene expression involved in milk biosynthesis, in ruminants. Moreover, nutrigenomic studies underline the role of the mammary structure and the potential influence of microRNAs. Knowledge from three lactating and three dairy livestock species contribute to understanding the variety of phenotypes reported in this review and highlight (1) the importance of critical physiological stages, such as puberty gestation and early lactation and (2) the relative importance of the various nutrients besides the total energetic value and their interaction.


Assuntos
Ração Animal/análise , Glândulas Mamárias Animais/crescimento & desenvolvimento , Leite/química , Ruminantes/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Lactação , Glândulas Mamárias Animais/química , Modelos Animais , Nutrigenômica
7.
PLoS One ; 16(2): e0246992, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33592025

RESUMO

The use of red grape pomace (GP; Vitis vinifera L. var. Shiraz) as a source of beneficial bioactive compounds in ruminant diets is limited by high levels of indigestible compounds in the grape skin matrix. This problem demands innovative, inexpensive, and easy-to-use strategies that improve the digestibility of GP. The bioconversion of GP using edible oyster mushrooms (Pleurotus ostreatus) is one such strategy that has not been previously explored. Therefore, this study evaluated the effect of cultivating oyster mushrooms on GP on chemical composition and in vitro ruminal fermentation parameters of the spent mushroom substrate. The GP was inoculated with oyster mushroom spawns at 0, 200, 300, 400, or 500 g/kg, and incubated for 4 weeks. Organic matter, acid detergent lignin, sodium, manganese, cobalt, and copper linearly declined (P < 0.05) as spawn rates increased. A quadratic trend was observed for crude protein, neutral detergent fibre, acid detergent fibre, magnesium, phosphorus, and calcium content in response to increasing spawn rates. Higher spawning rates (20-50%) had a positive effect (P < 0.05) on gas production from the immediately fermentable fraction (a), rate of gas production from the slowly fermentable fraction (c) and effective gas production. However, gas production from the slowly fermentable fraction (b) and potential gas production linearly declined in response to increasing spawning rates. There was a linear increase (P < 0.05) in the immediately degradable fraction (a), while quadratic effects were observed for partition factors, effective degradability, and in vitro organic matter degradability at 48 h in response to spawning rates. It can be concluded that inoculating GP with oyster mushroom spawn reduced fibre content while increasing crude protein content and in vitro ruminal fermentation efficiency of red grape pomace. Based on the quadratic responses of partition factors at 48 hours post-inoculation, the optimum spawning rate for maximum ruminal fermentation efficiency of GP was determined to be 300 g/kg.


Assuntos
Valor Nutritivo , Pleurotus/crescimento & desenvolvimento , Ruminantes/metabolismo , Vitis/química , Resíduos , Ração Animal/análise , Animais , Digestão , Fermentação , Pleurotus/metabolismo , Ruminantes/fisiologia
8.
BMC Vet Res ; 17(1): 25, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33419429

RESUMO

Ruminants are an important part of world animal production. The main factors affecting their production rates are age, diet, physiological condition and welfare. Disorders related to low level of welfare can significantly affect the microbiological composition of the digestive system, which is essential to maintain high production rates. The microbiology of the ruminant gastrointestinal tract may be significantly affected by inappropriate keeping system (especially in juveniles), psychological stress (e.g. transport), or heat stress. This results in an increased risk of metabolic diseases, reduced fertility and systemic diseases. Therefore, the paper focuses on selected disorders i.e., aforementioned inappropriate maintenance system, psychological stress, heat stress and their effects on the microbiome of the digestive system.


Assuntos
Criação de Animais Domésticos/métodos , Microbioma Gastrointestinal/fisiologia , Ruminantes/microbiologia , Bem-Estar do Animal , Animais , Dieta/veterinária , Resposta ao Choque Térmico , Ruminantes/fisiologia , Estresse Psicológico
9.
Methods ; 186: 42-51, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32758682

RESUMO

The rumen microbiome constitutes a dense and complex mixture of anaerobic bacteria, archaea, protozoa, virus and fungi. Collectively, rumen microbial populations interact closely in order to degrade and ferment complex plant material into nutrients for host metabolism, a process which also produces other by-products, such as methane gas. Our understanding of the rumen microbiome and its functions are of both scientific and industrial interest, as the metabolic functions are connected to animal health and nutrition, but at the same time contribute significantly to global greenhouse gas emissions. While many of the major microbial members of the rumen microbiome are acknowledged, advances in modern culture-independent meta-omic techniques, such as metaproteomics, enable deep exploration into active microbial populations involved in essential rumen metabolic functions. Meaningful and accurate metaproteomic analyses are highly dependent on representative samples, precise protein extraction and fractionation, as well as a comprehensive and high-quality protein sequence database that enables precise protein identification and quantification. This review focuses on the application of rumen metaproteomics, and its potential towards understanding the complex rumen microbiome and its metabolic functions. We present and discuss current methods in sample handling, protein extraction and data analysis for rumen metaproteomics, and finally emphasize the potential of (meta)genome-integrated metaproteomics for accurate reconstruction of active microbial populations in the rumen.


Assuntos
Criação de Animais Domésticos/métodos , Microbioma Gastrointestinal/fisiologia , Metagenômica/métodos , Proteômica/métodos , Rúmen/microbiologia , Animais , Interações entre Hospedeiro e Microrganismos/fisiologia , Gado/microbiologia , Gado/fisiologia , Metagenoma , Locos de Características Quantitativas/fisiologia , Ruminantes/microbiologia , Ruminantes/fisiologia
10.
Methods ; 186: 3-13, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32927085

RESUMO

The physiology of hyperthermia or heat stress in mammals is complex. It is a totally systemic condition that in varying degrees involves all organs, tissues and body fluid compartments. The nature and magnitude of the response is influenced by animal specific characteristics (e.g. age, diet, body condition, gender, reproductive stage), environment and animal management. Given the multifaceted nature of heat stress, and the varied ruminant production systems based in varied geoclimatic zones, it has been difficult to find appropriate measures of heat stress for production ruminants. This has become an urgent challenge as production systems intensify globally in a warming climate. Bioclimatic indices such as the Temperature-Humidity Index (THI) have evolved to incorporate some measure of animal physiology. However, these indices do not have strong relationships with core temperature trajectories and altered respiratory dynamics of animals with excessive heat load. In recent decades, the careful physiology studies of the 1950-80s, have given way to numerous studies trialling a plethora of new technologies and computational approached to measure heat stress. Infrared thermography of body surface temperatures, automated measures of respiration rate and radiotelemetry of internal body temperatures are the most intensively researched. The common goal has been to find the 'holy grail' decision-making threshold or timepoint as to the animal's wellbeing. Are we making any progress?


Assuntos
Resposta ao Choque Térmico/fisiologia , Hipertermia/diagnóstico , Gado/fisiologia , Monitorização Fisiológica/veterinária , Ruminantes/fisiologia , Animais , Temperatura Corporal/fisiologia , Monitorização Fisiológica/métodos
12.
PLoS One ; 15(12): e0241042, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33275623

RESUMO

We studied the habitat selection of pronghorn (Antilocapra americana) during seasonal migration; an important period in an animal's annual cycle associated with broad-scale movements. We further decompose our understanding of migration habitat itself as the product of both broad- and fine-scale behavioral decisions and take a multi-scale approach to assess pronghorn spring and fall migration across the transboundary Northern Sagebrush Steppe region. We used a hierarchical habitat selection framework to assess a suite of natural and anthropogenic features that have been shown to influence selection patterns of pronghorn at both broad (migratory neighborhood) and fine (migratory pathway) scales. We then combined single-scale predictions into a scale-integrated step selection function (ISSF) map to assess its effectiveness in predicting migration route habitat. During spring, pronghorn selected for native grasslands, areas of high forage productivity (NDVI), and avoided human activity (i.e., roads and oil and natural gas wells). During fall, pronghorn selected for native grasslands, larger streams and rivers, and avoided roads. We detected avoidance of paved roads, unpaved roads, and wells at broad spatial scales, but no response to these features at fine scales. In other words, migratory pronghorn responded more strongly to anthropogenic features when selecting a broad neighborhood through which to migrate than when selecting individual steps along their migratory pathway. Our results demonstrate that scales of migratory route selection are hierarchically nested within each other from broader (second-order) to finer scales (third-order). In addition, we found other variables during particular migratory periods (i.e., native grasslands in spring) were selected for across scales indicating their importance for pronghorn. The mapping of ungulate migration habitat is a topic of high conservation relevance. In some applications, corridors are mapped according to telemetry location data from a sample of animals, with the assumption that the sample adequately represents habitat for the entire population. Our use of multi-scale modelling to predict resource selection during migration shows promise and may offer another relevant alternative for use in future conservation planning and land management decisions where telemetry-based sampling is unavailable or incomplete.


Assuntos
Migração Animal , Ruminantes , Alberta , Animais , Conservação dos Recursos Naturais , Ecossistema , Feminino , Sistemas de Informação Geográfica , Atividades Humanas , Humanos , Modelos Lineares , Montana , Ruminantes/fisiologia , Saskatchewan , Estações do Ano
13.
J Dairy Res ; 87(S1): 34-46, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33213578

RESUMO

Diversity of production systems and specific socio-economic barriers are key reasons explaining why the implementation of new technologies in small ruminants, despite being needed and beneficial for farmers, is harder than in other livestock species. There are, however, helpful peculiarities where small ruminants are concerned: the compulsory use of electronic identification created a unique scenario in Europe in which all small ruminant breeding stock became searchable by appropriate sensing solutions, and the largest small ruminant population in the world is located in Asia, close to the areas producing new technologies. Notwithstanding, only a few research initiatives and literature reviews have addressed the development of new technologies in small ruminants. This Research Reflection focuses on small ruminants (with emphasis on dairy goats and sheep) and reviews in a non-exhaustive way the basic concepts, the currently available sensor solutions and the structure and elements needed for the implementation of sensor-based husbandry decision support. Finally, some examples of results obtained using several sensor solutions adapted from large animals or newly developed for small ruminants are discussed. Significant room for improvement is recognized and a large number of multiple-sensor solutions are expected to be developed in the relatively near future.


Assuntos
Bem-Estar do Animal , Indústria de Laticínios/instrumentação , Cabras/fisiologia , Monitorização Fisiológica/veterinária , Ruminantes/fisiologia , Ovinos/fisiologia , Acelerometria/instrumentação , Acelerometria/veterinária , Criação de Animais Domésticos/instrumentação , Criação de Animais Domésticos/métodos , Sistemas de Identificação Animal/instrumentação , Sistemas de Identificação Animal/veterinária , Animais , Indústria de Laticínios/métodos , Monitorização Fisiológica/instrumentação , Rúmen
14.
Sci Rep ; 10(1): 19655, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184385

RESUMO

Sargassum fusiforme, which is a type of brown algae, can provide fiber and minerals to ruminant diets. In this study, dried S. fusiforme was tested in vitro at four different doses 1, 3, 5, and 10% of the total ration for its effect on ruminal fermentation characteristics, and gas profiles when incubated for 72 h. At a level of 1 and 10%, S. fusiforme supplementation augmented total volatile fatty acid (VFA) concentrations compared to that with 0% supplementation. In addition, total gas, methane, and carbon dioxide emissions significantly decreased at 3 and 24 h of incubation at this dose. An in situ trial was performed for 72 h with S. fusiforme to evaluate it as a potential feed ingredient by comparing its degradation parameters with timothy hay (Phleum pretense). 1H nuclear magnetic resonance spectroscopy profiling was used to identify and quantify metabolites of S. fusiforme. Mannitol, guanidoacetate and ethylene glycol were largely accumulated in S. fusiforme. Moreover, nutritious minerals for feed ingredients were present in S. fusiforme. Whereas a high concentration of arsenic was found in S. fusiforme, it was within the allowable limit for ruminants. Our results suggest that S. fusiforme could represent an alternative, renewable feed ingredient for ruminant diets, with nutritional, as well as environmental, benefits.


Assuntos
Ração Animal/análise , Dieta , Digestão/fisiologia , Ácidos Graxos Voláteis/metabolismo , Rúmen/metabolismo , Ruminantes/fisiologia , Sargassum/química , Animais , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Fibras na Dieta , Fermentação , Metano/química , Metano/metabolismo , Sargassum/metabolismo
15.
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
16.
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
17.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1313-1320, July-Aug. 2020. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131486

RESUMO

Avaliou-se a maturidade pulmonar de cabritos no líquido amniótico de suas mães pela coloração de Shor, pelo azul de Nilo e pela contagem de corpos lamelares, bem como a vitalidade e os níveis de glicose e lactato séricos em cabritos nascidos a termo e prematuros. Para tanto, foram utilizados 32 cabritos, divididos em três grupos, a saber: grupo I: cabritos nascidos de cesarianas com 149 dias de gestação; grupo II: cabritos nascidos de cesarianas com 143 dias de gestação; e grupo III: cabritos nascidos de cesarianas com 143 dias de gestação, oriundos de mães que receberam, por via intramuscular, 20mg/cabra de dexametasona, 36 horas antes da cirurgia eletiva. A coloração de Shorr e a contagem de corpos lamelares demonstraram ser métodos diagnósticos promissores para a avaliação da maturidade pulmonar em neonatos caprinos. Contudo, a administração de dexametasona nas cabras no período antenatal não influenciou a maturidade fetal. Constatou-se, entretanto, que a avaliação física do paciente, logo após o nascimento, também se mostra fundamental no que tange à percepção da vitalidade e da viabilidade de cabritos recém-nascidos.(AU)


Pulmonary maturity of goats in their amniotic fluid was evaluated by Shor, Nile blue staining, and lamellar body count, as well as vitality and serum glucose and lactate levels in term and premature goats. Twenty-four kids were divided into three groups: group I: comprised of eight animals born by cesarean section with 149 days of gestation; group II: comprised of eight animals born by cesarean section with 143 days of gestation; and group III: comprised of eight animals born by cesarean section with 143 days of gestation, in which the does received intramuscular dexamethasone (20mg/goat) 36 hours prior to elective cesarean section. Shorr staining and lamellar body count have shown to be promising diagnostic methods for the assessment of lung maturity in goat neonates. However, the administration of dexamethasone to goats during antenatal period did not influence fetal maturity. It was verified that the physical evaluation of the patient, shortly after birth, is fundamental for the perception of vitality and viability of newborn goats.(AU)


Assuntos
Animais , Ruminantes/crescimento & desenvolvimento , Ruminantes/fisiologia , Pulmão/crescimento & desenvolvimento , Recém-Nascido Prematuro , Desenvolvimento Fetal/fisiologia , Líquido Amniótico
18.
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
19.
Zool Res ; 41(4): 455-457, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32543790

RESUMO

Infanticide by unrelated individuals is widely reported in the animal kingdom; however, little is known about cases perpetrated by a parent, particularly the mother. This article reports on three cases of mother-initiated infanticide in Qinling golden takins ( Budorcas taxicolor bedfordi) recorded from video and camera images. Based on previous reports in other animals, we propose that the infanticide events observed in golden takins were related to the parental manipulation mechanism - i.e., killing an unhealthy infant to allow the mother to invest more care in potentially healthy offspring, and gain more fruitful reproductive opportunities. This appears to be an evolutionary-based selection strategy, whereby a species can prosper and succeed under the challenges of natural selection. However, further studies on both captive and wild populations are required to answer the various questions raised from our observations.


Assuntos
Agressão , Comportamento Animal , Morte , Ruminantes/fisiologia , Animais , Mães
20.
Sci Rep ; 10(1): 8241, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427930

RESUMO

Monitoring populations and designing effective conservation actions for endangered species present significant challenges. An accurate understanding of current distribution, ecological traits and habitat requirements is imperative in formulating conservation strategies. Recent surveys on the southernmost Cuvier's Gazelle (Gazella cuvieri) population, an ungulate endemic to North Africa, showcase its importance in terms of numbers and genetic diversity. This population inhabits a remote region in the extreme north-western portion of the Sahara Desert and has not been well studied. Here, we examine the potential distribution of Cuvier's Gazelle and the environmental factors limiting the species in a Saharan environment, by combining broad-scale field survey data and species distribution models. Our objective was to identify high priority conservation areas in the southernmost known portion of the species' distribution by modelling habitat selection at the landscape scale using a predictive distribution map. Our results show that the distribution of Cuvier's Gazelle is strongly related to mountainous areas with heterogeneous terrain and remoteness from large human settlements over other ecological factors that had less impact on the species' presence and distribution. We also provide a quantitative estimate of the potential distribution range of Cuvier's Gazelle in southern Morocco, identifying two well-demarcated key areas. The two core areas currently contain enough rugged terrain isolated from human encroachment to support the endangered species in this harsh desert environment. We encourage the implementation of conservation planning for Cuvier's Gazelle as an "umbrella species", which will confer effective protection to higher-quality habitat zones and co-occurring species, leading to sustainable and ecologically responsible development in the region.


Assuntos
Espécies em Perigo de Extinção/estatística & dados numéricos , Ruminantes/fisiologia , África do Norte , Distribuição Animal , Animais , Conservação dos Recursos Naturais , Ecossistema , Marrocos , Ruminantes/crescimento & desenvolvimento
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