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1.
Sci Total Environ ; 743: 140665, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32927525

RESUMO

This study screened six different species of forest plants and then further evaluated the most promising plant, giant milkweed (Calotropis gigantea), for the potential to improve nitrogen utilization efficiency (NUE) through inhibiting rumen protozoa in vitro. Ground leaves of giant milkweed at 1.6 and 3.2 mg/mL decreased the counts of Entodinium cells by 41.30% and 58.89%, respectively, and damaged their cell surface structure. Dasytricha, Isotricha, Epidinium, Ophryoscolex, and Diplodinium were not affected, while total bacterial and archaeal populations did not decrease. Ammonia nitrogen (NH3-N) concentration decreased by 50.64% and 33.33% at 1.6 g/mL and 3.2 mg/mL, respectively. Volatile fatty acid (VFA) production and methane production remained unaffected, but butyrate production increased. The giant milkweed leaves contained (per gram of dry matter) 3636 µg phenolics including 205.9 µg of 3-hydroxybenzoic acid, 2079 µg flavonoids including 1197.5 µg of quercetin and 91.4 µg of myricetin, and 490 µg alkaloids including 219.8 µg of anthraquinone glycosides. The effective inhibition of Entodinium was accompanied by a decrease in NH3-N concentration, and methane production did not increase except for the dose of 1.6 mg/mL. Giant milkweed may be used as a new feed additive or an alternative to chemicals or antibiotics for sustainable animal husbandry enhancing NUE in ruminants.


Assuntos
Calotropis , Cilióforos , Microbiota , Ração Animal , Animais , Dieta , Fermentação , Metano , Rúmen
2.
Anim Sci J ; 91(1): e13438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32761765

RESUMO

The objective was to investigate the influence of crude protein (CP) content in a fattening diet on feed intake, body weight gain, nitrogen excretion, and carcass traits in Holstein steers. Steers (initial body weight 241 ± 26 kg) consumed feed with the following CP content: (a) 17.7% during the early period (from 7 to 10 months of age) and 13.9% during the late period (from 11 to 18 months of age) (HIGH, n = 3), and (b) 16.2% during the early period and 12.2% during the late period (LOW, n = 4). The CP intake was lower in the LOW than the HIGH group. Urinary and total nitrogen excretion in the late period tended to be lower (p < .10) in the LOW than the HIGH group. However, growth performance and carcass traits were not affected by dietary CP content. Free histidine and total amino acid contents in the longissimus thoracis muscle tended to be higher (p < .10) in the HIGH than the LOW group, however, the CP contents were not affected by dietary CP content. The results of this experiment suggest that decreasing dietary CP to 16% (early period) or 12% (late period) of dry matter would reduce nitrogen excretion from Holstein fattening farms without affecting productivity.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Bovinos/metabolismo , Bovinos/fisiologia , Dieta/veterinária , Proteínas na Dieta/análise , Nitrogênio/metabolismo , Ganho de Peso , Animais , Masculino
3.
Anim Sci J ; 91(1): e13352, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32783336

RESUMO

Vitamin E is an essential nontoxic fat-soluble micronutrient whose effects on livestock performance and products can be attributed to its antioxidant and nonantioxidant properties. Although it is needed in small quantity in the diet, its roles in livestock production are indispensable as it is required in boosting performance, nutritional qualities, and yield of animal and animal products. The dietary or oral supplementation of vitamin E is essential in reducing lipid oxidation in muscle, egg, and dairy products as well as lowering cholesterol concentrations and improving antioxidant status of livestock. Evidence has shown that bioavailability of vitamin E-enriched animal products could serve as an invaluable nutritional benefit to consumers; especially those in regions of limited resources where vitamin E deficiencies pose a risk that may be detrimental to some cellular activities of the body and on human health. It is therefore important to redirect research on the impact of vitamin E supplementation as antioxidant on livestock performance and animal products.


Assuntos
Ração Animal , Dieta/veterinária , Gado , Vitamina E , Animais , Antioxidantes , Disponibilidade Biológica , Suplementos Nutricionais , Diterpenos , Vitamina E/metabolismo , Deficiência de Vitamina E
4.
Environ Monit Assess ; 192(9): 590, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32820434

RESUMO

Organoarsenic compounds are widely used in chicken feed for control of coccidial parasite, quick weight gain, and for imparting attractive color to the chicken flesh. A study was conducted to assess the level of arsenic in both chicken feed and flesh. Chicken feed was collected from 10 farm houses and total arsenic was estimated. The quantitative estimation suggests that the four levels of chicken feed contain different quantities of arsenic load. The results demonstrated that feed at stages III and IV levels contain 0.01 mg/g and 0.018 mg/g of arsenic respectively. However, at stages I and II levels, the feed contains 0.005 mg/g and 0.0052 mg/g of arsenic respectively. Proceeding similarly, chicken flesh was collected from ten vendors in the local markets of Burdwan. The experimental results revealed that deposition of arsenic in different parts of chicken body is not same. The highest accumulation was recorded in the flesh of chest followed by stomach, whereas flesh of the legs and heart showed lower levels of arsenic accumulation. A comprehensive calculation was thereafter done to assess the total amount of arsenic ingestion through consumption of chicken. If a person takes 60.0 g of chicken flesh (leg, breast, muscles, and stomach) everyday, then the person may consume 0.186-0.372 µg of arsenic per day. This study therefore clearly suggests that excessive consumption of poultry chicken may prove to be fatal. However, further research is necessary to confirm the present findings. To the best of our knowledge, this is probably the first report on the likelihood of arsenic contamination in the flesh of different body parts of poultry chicken from Eastern India.


Assuntos
Arsênico/análise , Ração Animal/análise , Animais , Galinhas , Monitoramento Ambiental , Índia , Prevalência
5.
Waste Manag ; 117: 58-80, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805602

RESUMO

Population growth and unprecedented economic growth and urbanization, especially in low- and middle-income countries, coupled with extreme weather patterns, the high-environmental footprint of agricultural practices, and disposal-oriented waste management practices, require significant changes in the ways we produce food, feed and fuel, and manage enormous amounts of organic wastes. Farming insects such as the black soldier fly (BSF) (Hermetia illucens) on diverse organic wastes provides an opportunity for producing nutrient-rich animal feed, fuel, organic fertilizer, and biobased products with concurrent valorization of wastes. Inclusion of BSF larvae/pupae in the diets of poultry, fish, and swine has shown promise as a potential substitute of conventional feed ingredients such as soybean meal and fish meal. Moreover, the bioactive compounds such as antimicrobial peptides, medium chain fatty acids, and chitin and its derivatives present in BSF larvae/pupae, could also add values to the animal diets. However, to realize the full potential of BSF-based biorefining, more research and development efforts are necessary for scaling up the production and processing of BSF biomass using more mechanized and automated systems. More studies are also needed to ensure the safety of the BSF biomass grown on various organic wastes for animal feed (also food) and legalizing the feed application of BSF biomass to wider categories of animals. This critical review presents the current status of the BSF technology, identifies the research gaps, highlights the challenges towards industrial scale production, and provides future perspectives.


Assuntos
Dípteros , Eliminação de Resíduos , Simuliidae , Ração Animal , Animais , Dieta , Larva , Suínos
6.
PLoS One ; 15(7): e0235895, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697784

RESUMO

The objective of this study was to determine if commercially collected liquid porcine plasma contaminated with African swine fever virus (ASFV) and fed for 14 consecutive days would infect pigs. Commercially collected liquid porcine plasma was mixed with the serum from an ASFV experimentally infected pig. To simulate the potential of pigs slaughtered being ASFV viremic but asymptomatic and passing antemortem inspection, the ratio of liquid plasma from healthy animals to serum from an ASFV infected pig used in this study represented 0.4% or 2.0% of the pigs slaughtered being viremic (Studies 1 or 2, respectively). The contaminated liquid plasma was mixed on commercial feed and pigs were fed for 14 consecutive days providing to each pig 104.3 or 105.0 TCID50 ASFV daily (Studies 1 or 2, respectively). Pigs were observed for an additional 5 or 9 days (Studies 1 or 2, respectively). In both experiments, the pigs did not become infected with ASFV during the 14d feeding period or during the subsequent observation period. In these experiments, unprocessed liquid plasma contaminated with ASFV mixed on commercial feed and fed for 14 consecutive days did not infect pigs. From our results we can conclude that the infectious dose of ASFV on feed is much higher than that previously reported, at least with ASFV-spiked raw plasma.


Assuntos
Vírus da Febre Suína Africana/patogenicidade , Febre Suína Africana/transmissão , Ração Animal/virologia , Plasma/virologia , Febre Suína Africana/virologia , Animais , Feminino , Masculino , Suínos
7.
PLoS One ; 15(7): e0229314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706777

RESUMO

INTRODUCTION: Many arboviruses of public health significance are maintained in zoonotic cycles with complex transmission pathways. The presence of serum antibody against arboviruses in vertebrates provides evidence of their historical exposure but reveals nothing about the vector-reservoir relationship. Moreover, collecting blood or tissue samples from vertebrate hosts is ethically and logistically challenging. We developed a novel approach for screening the immune status of vertebrates against Ross River virus that allows us to implicate the vectors that form the transmission pathways for this commonly notified Australian arboviral disease. METHODS: A micro-plaque reduction neutralisation test (micro-PRNT) was developed and validated on koala (Phascolarctos cinereus) sera against a standard PRNT. The ability of the micro-PRNT to detect RRV antibodies in mosquito blood meals was then tested using two mosquito models. Laboratory-reared Aedes aegypti were fed, via a membrane, on sheep blood supplemented with RRV seropositive and seronegative human sera. Aedes notoscriptus were fed on RRV seropositive and seronegative human volunteers. Blood-fed mosquitoes were harvested at various time points after feeding and their blood meals analysed for the presence of RRV neutralising antibodies using the micro-PRNT. RESULTS: There was significant agreement of the plaque neutralisation resulting from the micro-PRNT and standard PRNT techniques (R2 = 0.65; P<0.0001) when applied to RRV antibody detection in koala sera. Sensitivity and specificity of the micro-PRNT assay were 88.2% and 96%, respectively, in comparison with the standard PRNT. Blood meals from mosquitoes fed on sheep blood supplemented with RRV antibodies, and on blood from RRV seropositive humans neutralised the virus by ≥50% until 48 hr post feeding. The vertebrate origin of the blood meal was also ascertained for the same samples, in parallel, using established molecular techniques. CONCLUSIONS: The small volumes of blood present in mosquito abdomens can be used to identify RRV antibodies and therefore host exposure to arbovirus infection. In tandem with the accurate identification of the mosquito, and diagnostics for the host origin of the blood meal, this technique has tremendous potential for exploring RRV transmission pathways. It can be adapted for similar studies on other mosquito borne zoonoses.


Assuntos
Aedes/metabolismo , Ração Animal/análise , Anticorpos Antivirais/análise , Testes de Neutralização/métodos , Vírus do Rio Ross/imunologia , Aedes/virologia , Infecções por Alphavirus/diagnóstico , Infecções por Alphavirus/transmissão , Infecções por Alphavirus/veterinária , Ração Animal/virologia , Animais , Anticorpos Antivirais/sangue , Vetores de Doenças , Feminino , Humanos , Phascolarctidae/virologia , Sensibilidade e Especificidade
8.
Toxicon ; 185: 203-212, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32687887

RESUMO

The mycotoxin deoxynivalenol (DON) contaminates animal feed worldwide, frequently resulting in poor performance and economic losses. Data concerning the effects on poultry health or focusing on intestinal toxicity or the response to oxidative stress are scarce. Also, there is a need for strategies to mitigate the negative effects of DON. This study aimed to investigate the effects of Lactobacillus spp. treatments on the intestine, liver and kidney of poultry fed a DON-contaminated diet. To achieve this aim, histological, morphometrical and histochemical assays were performed. The oxidative stress response was also analyzed by the tests: reduced glutathione, ferric reducing ability, reducing of 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), nitro blue tetrazolium detection of superoxide anion, and thiobarbituric acid reactive substances. One-day-old broilers chickens (n 50) were submitted to the following treatments: control, DON (19.3 mg kg-1), viable Lactobacillus spp. + DON (VL + DON), heat-inactivated Lactobacillus spp. + DON (HIL + DON), Lactobacillus spp. culture supernatant + DON (LCS + DON). The animals received the contaminated diet for seven days. DON increased the intestinal and liver lesion score, while the Lactobacillus spp. treatments (LT) remained like the control. DON reduced the villi height and increased the crypt depths. The LT showed crypt depths similar to control, and higher villi: crypt ratio in duodenum and jejunum. In the ileum, the LT reduced the goblet cell count in relation to DON group. DON increased the number of intraepithelial lymphocytes (IEL) in jejunum and ileum, while the VL + DON treatment induced a significant decrease in IEL in comparison to DON. DON-diet induced an oxidative stress response in the intestine and liver, and also reduced the antioxidant capacity in these tissues, while LT treatments remained mostly similar to control. DON induced no change in redox balance in the kidney. The LT improved the intestinal health after DON acute exposure, reducing the oxidative stress damage mainly on jejunum and liver.


Assuntos
Galinhas/microbiologia , Micotoxinas/toxicidade , Estresse Oxidativo/fisiologia , Tricotecenos/toxicidade , Ração Animal , Animais , Contaminação de Alimentos , Intestinos , Lactobacillus
9.
Environ Sci Pollut Res Int ; 27(30): 37677-37683, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32608001

RESUMO

The study aimed to investigate the effect of Se sources and concentrations on performance, thyroid activity, antioxidant defense, and functional egg quality of Japanese quail. One hundred and twenty, 8-week-old birds were randomly assigned to 1 of 4 dietary treatments in 3 replicates (10 birds/replicate). The treatments contained inorganic sodium selenite (SS) at 0.2 mg/kg diet (SS1 = control) or 0.4 mg/kg diet (SS2) or selenomethionine (SM) at 0.2 mg/kg diet (SM1) or 0.4 mg/kg diet (SM2). Egg production (%) and feed intake were daily recorded, and feed conversion ratio (FCR) was calculated. Blood samples were collected and analyzed for glucose, thyroxine (T4), triiodothyronine (T3), glutathione peroxidase (GPX), and superoxide dismutase (SOD) enzymes. Egg quality was determined in terms of Se content and concentrations of triglycerides, LDL, HDL, and cholesterol. Dietary supplementation of SM2 increased (P < 0.05) egg production (%) and egg mass and decreased FCR compared to the other groups, which showed no significant differences (P > 0.05) in between. It is the first study reporting that the eggs from the quail fed SM2 diet had lower concentrations (P < 0.05) of triglycerides, LDL, and cholesterol than those fed SS. Feeding SM increased (P < 0.05) blood glucose, T4, and T3 levels. Moreover, feeding SM increased the activity of GPX and SOD with a higher significance (P < 0.05) for SM2 than SM1. In conclusion, no adverse effects from supplementation of SM up to 0.4 mg/kg were observed and could improve their performance, antioxidant defense, thyroid activity, and functional egg quality.


Assuntos
Antioxidantes , Coturnix , Ração Animal/análise , Animais , Dieta , Suplementos Nutricionais , Ovos
10.
An Acad Bras Cienc ; 92 Suppl 1: e20190278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638858

RESUMO

To examine the association between phytase and xylanase in diets with nutritional adjustments on intestinal morphometry, serum biochemistry and microbiology of broilers, 250 broilers were evaluated in a completely randomized design with five treatments and five replicates. The following treatments were tested: positive control diet - without phytase or xylanase; negative control diet - with an energy reduction of 100 kcal/kg, without phytase or xylanase; and three diets containing xylanase and phytase and energy reductions of 50, 100 and 150 Kcal/kg. For all energy-reduced diets, the nutritional matrix of phytase with phosphorus (0.15%), calcium (0.165%) and sodium (0.035%) was considered. An effect of the association between enzyme inclusion and metabolizable energy reduction in the diets was observed only by contrast analysis, for villus height. Intestinal health was not changed. Only the serum phosphorus concentration was altered by the treatments at the different evaluated ages. The association of phytase (500 FTU/kg) with xylanase (16000 BXU/kg) in diets with reductions of up to 150 Kcal/kg metabolizable energy, 0.15% digestible P, 0.165% Ca and 0.035% Na does not alter the intestinal morphometry, serum biochemistry or microbiology of broilers.


Assuntos
Galinhas , 6-Fitase , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Suplementos Nutricionais , Digestão , Endo-1,4-beta-Xilanases , Fósforo
11.
An Acad Bras Cienc ; 92 Suppl 1: e20190140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638863

RESUMO

The objective of the present study was to evaluate growth, biochemical, hematological and intestinal enzymes responses and survival of Nile tilapia juveniles fed a diet containing the essential oil of lemongrass Cymbopogum flexuosus (EOCF) and infected by Aeromonas hydrophila. Five diets were evaluated (in quadruplicate) with increasing levels of EOCF (0.0 - control; 0.25; 0.50; 1.0 and 2.0 mL kg diet-1). On day 45, eight fish per treatment were sampled and blood, liver and intestine samples were taken. Others eight fish per treatment were infected with A. hydrophila followed by a 15-day period of observation. Citral is the main constituent of EOCF. The inclusion of 2.0 mL EOCF kg diet-1 increased specific growth rate and survival after A. hydrophila infection and decreased feed conversion ratio of Nile tilapia. In general, higher concentrations of EOCF in the diet reduced plasma glucose and triglycerides levels, and increased plasma amino acids, alanine aminotransferase (ALT) and hepatic ALT levels, hematological parameters, and the activity of intestinal enzymes. It was concluded that the inclusion of 2.0 mL EOCF kg diet-1 improved growth performance, biochemical and physiological responses and decreased mortality of Nile tilapia after A. hydrophila infection.


Assuntos
Ciclídeos , Cymbopogon , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila , Ração Animal , Animais , Dieta , Suplementos Nutricionais , Infecções por Bactérias Gram-Negativas/veterinária , Óleos Voláteis
12.
Environ Pollut ; 266(Pt 3): 115156, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32663629

RESUMO

The aquatic ecosystem is seriously damaged because of the heavy use of pesticides and antibiotics. Fish is the indispensable link between environmental pollution and human health. However, the toxic effects of environment-related concentrations of pesticides and antibiotics in fish have not been thoroughly studied. In this study, grass carps exposed to cypermethrin (CMN, 0.651 µg/L) or/and sulfamethoxazole (SMZ, 0.3 µg/L) for 42 days caused oxidative stress, apoptosis and immunodeficiency in the spleen of grass carps. CMN or/and SMZ exposure led to oxidative damage (consumption of antioxidant enzymes (superoxide dismutase and catalase)) and lipid peroxidation (accumulation of malondialdehyde), induced apoptosis (increases in TUNEL index, Bax/bcl-2, p53, puma and Caspase family expression). In addition, the levels of immunoglobulin M (IgM), complement 3 (C3) were significantly decreased in all treatment groups, which trend was also found in C-reactive protein in CMN and MIX group, and lysozyme in MIX group. Transcription of almost all genes involved in the Toll-like receptors (TLR) signaling pathway was up-regulated under CMN or/and SMZ exposure. However, when subsequently attacked by Aeromonas hydrophila for 2 days, the TLR pathway was inhibited in spleens of all treatment groups accompanied by higher mortality. Overall, the environmentally relevant concentration of CMN and SMZ damages the immune system, triggering oxidative stress and apoptosis in carps. And by affecting the conduction of TLR signaling pathway, CMN or/and SMZ exposure inhibits the innate immune response of fish and reducing their disease resistance. This study highlights the importance of rational and regulated use of these pesticides and antibiotics.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Ursidae , Aeromonas hydrophila , Ração Animal/análise , Animais , Dieta , Ecossistema , Proteínas de Peixes , Imunidade Inata , Piretrinas , Sulfametoxazol
13.
PLoS One ; 15(7): e0235109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609724

RESUMO

Data on the transfer of artificial radionuclides from the environment to the food supply is necessary for internal dose assessment. There is a necessity for expanding and improving the available information on these factors in order to make better dose models for specific scenarios. This paper describes the results of a field experiment with broiler chickens on the transfer factor (Ff) and concentration ratio (CR) for the long-term intake of 241Am and 137Cs with grass meal and soil. The broilers were divided into two groups, each group had nine subgroups and each subgroup had three broilers. The radionuclide concentrations in the feed and the thigh muscle, thigh bone, and liver of 54 broilers divided between the grass meal and soil groups were evaluated by gamma spectrometry for 241Am and 137Cs. The duration of feeding with "contaminated" sources ranged between 1-70 days. The equilibrium stage of 241Am in muscle and bone occurs on the 1st and 40th day, respectively; for 137Cs in muscle- 30th days of intake and for liver and bone- 7th days. For 241Am, the liver did not reach equilibrium stage during the 70 days of intake. Ff of 137Cs in the "forage-muscle" and "soil-muscle" systems were determined as 1.9±0.3 and 0.18±0.05; Ff of 241Am in the "soil-muscle" system was-7.5×10-5.


Assuntos
Amerício/análise , Radioisótopos de Césio/análise , Galinhas , Contaminação Radioativa de Alimentos/análise , Aves Domésticas , Poluentes Radioativos do Solo/análise , Amerício/metabolismo , Ração Animal/análise , Animais , Radioisótopos de Césio/metabolismo , Galinhas/metabolismo , Abastecimento de Alimentos , Aves Domésticas/metabolismo , Poluentes Radioativos do Solo/metabolismo
14.
PLoS One ; 15(7): e0235054, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609728

RESUMO

Elucidating the diets of insect predators is important in basic and applied ecology, such as for improving the effectiveness of conservation biological control measures to promote natural enemies of crop pests. Here, we investigated the aphid diet of two common aphid predators in Central European agroecosystems, the native Coccinella septempunctata (Linnaeus) and the invasive Harmonia axyridis (Pallas; Coleoptera: Coccinellidae) by means of high throughput sequencing (HTS). For acquiring insights into diets of mobile flying insects at landscape scale minimizing trapping bias is important, which imposes methodological challenges for HTS. We therefore assessed the suitability of three field sampling methods (sticky traps, pan traps and hand-collection) as well as new aphid primers for identifying aphid prey consumption by coccinellids through HTS. The new aphid primers facilitate identification to species level in 75% of the European aphid genera investigated. Aphid primer specificity was high in silico and in vitro but low in environmental samples with the methods used, although this could be improved in future studies. For insect trapping we conclude that sticky traps are a suitable method in terms of minimizing sampling bias, contamination risk and trapping success, but compromise on DNA-recovery rate. The aphid diets of both field-captured ladybird species were dominated by Microlophium carnosum, the common nettle aphid. Another common prey was Sitobion avenae (cereal aphid), which got more often detected in C. septempunctata compared to H. axyridis. Around one third of the recovered aphid taxa were common crop pests. We conclude that sampling methodologies need constant revision but that our improved aphid primers offer currently one of the best solutions for broad screenings of coccinellid predation on aphids.


Assuntos
Afídeos/genética , Besouros/fisiologia , Cadeia Alimentar , Comportamento Predatório , Ração Animal/análise , Animais , Afídeos/classificação , DNA/análise , DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Espécies Introduzidas , Especificidade da Espécie
15.
Br Poult Sci ; 61(4): 471-481, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32683884

RESUMO

1. This study quantified xylanase-induced changes in soluble monosaccharides, xylooligosaccharides (XOS) and volatile fatty acid (VFA) contents of the different sections of the gastrointestinal tract (GIT) and whether these were related to altered bird performance. 2. An in vitro digestion of the wheat-based diet was carried out with the xylanase (Econase XT at 16,000BXU/kg diet) to compare the in vitro and in vivo generation of these XOS and monosaccharides. For the in vivo study, 80 male Ross 508 b roiler chicks were split into two groups fed a wheat-based diet with or without Econase XT (16,000BXU/kg diet) for 21 days. 3. There were no effects of Econase XT inclusion on growth performance characteristics, likely a result of the high-quality wheat diet, the corresponding high performance of the control group (FCR average of 1.45 in controls) and the relatively young age of the birds (from four to 26 days of age). 4. Econase XT supplementation increased the xylotetraose (X4) content in the colon (P = 0.046, enzyme x GIT section interaction) and the xylose contents in the colon and caeca (P < 0.001, enzyme x GIT section interaction). 5. The trend for increased acetate production in the caeca of Econase XT treated birds (P = 0.062) suggested that the XOS generated were subsequently fermented in the caeca, potentially impacting upon the types of microbiota present. 6. The present study suggested that wheat arabinoxylan degradation was enhanced by xylanase supplementation, which may have increased the production of beneficial volatile fatty acids (VFA) in the caeca, and thereby potentially modulated the caecal microbiome, but without affecting bird performance at this early age.


Assuntos
Galinhas , Triticum , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Suplementos Nutricionais , Digestão , Endo-1,4-beta-Xilanases , Glucuronatos , Masculino , Monossacarídeos , Oligossacarídeos
16.
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
17.
An Acad Bras Cienc ; 92 Suppl 1: e20180787, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32725067

RESUMO

The present study was planned to test the hypothesis that feeding lactating dairy cattle with varying levels of rumen-undegradable protein (RUP) can enhance protein utilization, milk production, milk protein, and nitrogen (N) excretion. Forty mid-lactating crossbred (Jersey × Friesian) cattle were randomly divided into four groups. Four treatment diets were formulated to contain 30%, 40%, 50%, and 60% RUP of crude protein. Dry matter (DM) and crude protein intakes were significantly reduced with increasing dietary RUP levels. Crude protein digestibility increased linearly with incremental increases in dietary RUP levels. Cattle fed 60% RUP showed a linear decrease in N intake compared to that in the other groups. A linear decrease in urinary N and linear increases in net N, milk N, and N-use efficiency were observed with increasing dietary RUP levels. Actual milk, energy-corrected milk, and 4% fat-corrected milk yields (kg/day) increased linearly with an increasing degradability of protein. However, milk protein, solids not fat and total solids, as well as the yields of protein, fat, and lactose, showed significant increases with increased RUP supplementation. Collectively, the results indicate that formulating dairy cow diets to contain 60% RUP results in better lactating performance and N-use efficiency and lower N excretion.


Assuntos
Lactação , Rúmen , Ração Animal , Animais , Bovinos , Dieta , Digestão , Feminino , Nitrogênio , Nutrientes
18.
PLoS One ; 15(7): e0234610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645008

RESUMO

The objective of this study was to evaluate the effect of the physical form of starter and inclusion of hay in the diet of preweaning dairy calves on performance, digestibility, ruminal development, and mRNA expression of genes involved in ruminal metabolism. Holstein × Gyr crossbred male calves (n = 38 1day old) were assigned to 3 treatments for 9 weeks: Control (n = 13; pellet starter with 4 mm diameter and 18 mm length and 4% steam-flaked corn), Ground (n = 12; same starter of the control but ground pass through a 4.0 mm sieve), or Ground plus 5% chopped Tifton hay GH (n = 13). All calves were fed 4 L/d of whole milk up to 63 d of age and were abruptly weaned at 64 d of age. Water and diets were offered ad libitum. Samples of ruminal contents were obtained from all animals at 30, 45, and 60 d of age to evaluate pH, ammonia nitrogen, and volatile fatty acids (VFA). At 55 d of age, an apparent digestibility assay was performed using 18 animals (n = 6/ treatment). At 65 d of age, the 18 animals were euthanized to evaluate the development of the digestive tract. The physical form of starter and the dietary inclusion of hay did not influence starter intake (Control 326 g/d, Ground 314 g/d and GH 365 g/d), daily weight gain (Control 541g/d, Ground 531g/d and GH 606g/d), feed efficiency, apparent nutrient digestibility, energy partitioning, nitrogen balance, ruminal pH, ammonia nitrogen concentration, VFA, the development of the digestive tract and the mRNA expression of genes involved in AGV metabolism.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Dieta/veterinária , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso Corporal , Bovinos , Fibras na Dieta/metabolismo , Masculino , Leite/metabolismo , Nutrientes , Rúmen/metabolismo , Desmame , Ganho de Peso , Zea mays/metabolismo
19.
J Zoo Wildl Med ; 51(2): 433-437, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549575

RESUMO

Elephant endotheliotropic herpesvirus (EEHV) hemorrhagic disease (EEHV-HD) threatens Asian elephant (Elephas maximus) population sustainability in North America. Clusters of cases have also been reported in African elephants (Loxodonta africana). Risk to range country elephant populations is unknown. Currently, EEHV detection depends upon sampling elephants trained for invasive blood and trunk wash collection. To evaluate noninvasive sample collection options, paired invasively collected (blood, trunk wash and oral swabs), and noninvasively collected (chewed plant and fecal) samples were compared over 6 wk from 9 Asian elephants and 12 African elephants. EEHV shedding was detected simultaneously in a paired trunk wash and fecal sample from one African elephant. Elephant γ herpesvirus-1 shedding was identified in six chewed plant samples collected from four Asian elephants. Noninvasively collected samples can be used to detect elephant herpesvirus shedding. Longer sampling periods are needed to evaluate the clinical usefulness of noninvasive sampling for EEHV detection.


Assuntos
Betaherpesvirinae/isolamento & purificação , Elefantes , Infecções por Herpesviridae/veterinária , Manejo de Espécimes/veterinária , Ração Animal/virologia , Animais , Animais de Zoológico , Coleta de Amostras Sanguíneas/veterinária , Fezes/virologia , Feminino , Microbiologia de Alimentos , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/virologia , Irlanda , Masculino , Manejo de Espécimes/classificação , Manejo de Espécimes/instrumentação
20.
Int J Syst Evol Microbiol ; 70(7): 4224-4232, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32553048

RESUMO

A Gram-stain-negative, long-rod-shaped and facultative aerobic bacterium, designated HB-1T, was isolated from a round hay bale at the Kansas State University Beef Stocker Unit. The results of phylogenetic analysis of 16S rRNA gene sequences indicated that strain HB-1T clustered within the genus Gemmobacter and its closest relatives were Gemmobacter aquaticus A1-9T (98.0 %), Gemmobacter lutimaris YJ-T1-11T (98.0 %), Gemmobacter fontiphilus JS43T (97.8 %), Gemmobacter aquatilis DSM 3857T (97.5 %) and Gemmobacter lanyuensis Orc-4T (96.9 %). Additional phylogenomic analysis also indicated that strain HB-1T belongs to the genus Gemmobacter. The draft genome of strain HB-1T had a total length of 4.23 Mbp and contained 4071 protein-coding genes. The average nucleotide identity values between the genomes of strain HB-1T and the three most-related type strains ranged from 77.5 to 78.1 %. The DNA G+C content of strain HB-1T was 63.7 mol%. The novel strain grew at 10-37 °C, pH 5-10 and with 0-2 % NaCl. Oxidase and catalase activities were positive. Cells were 0.3-0.4 µm wide, 3.0-7.0 µm long and usually found in pairs or chains of cells. The major respiratory quinone of strain HB-1T was Q-10 (90 %), with a minor amount of Q-9 (10 %). The major fatty acids were C18 : 1 ω7c (54.6 %) and C16 : 0 (18.2 %). On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain HB-1T (=DSM 109828T=ATCC TSD-211T) is considered to represent a novel species of the genus Gemmobacter, for which the name Gemmobacter serpentinus sp. nov. is proposed.


Assuntos
Ração Animal/microbiologia , Filogenia , Rhodobacteraceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Kansas , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
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