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1.
J Agric Food Chem ; 67(34): 9460-9467, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31381328

RESUMO

Understanding the water isotopes in feed products derived from grass is fundamental for tracing domestic animal products. Grass silage water was reported to have fewer heavy isotopes than fresh grass, but it is still unknown whether dew formation (either dewfall or dewrise), exchange with soil water, or other processes override the expected enrichment of heavy isotopes due to wilting. The isotopic variations of water (δ2H, δ18O) in fresh grass and cut grass during wilting on soil and on plastic were compared in this study. Drying enriched heavier isotopes, but this was overridden by three processes that finally caused low δ2H and δ18O values: (i) the adsorption of humidity from the surroundings, (ii) the exchange with humidity, and (iii) the depletion of heavy water isotopes close to organic surfaces, called the surface effect, which was the most dominant effect at the end of drying when the water content became low.


Assuntos
Isótopos de Oxigênio/análise , Poaceae/química , Água/química , Deutério/análise , Pradaria , Umidade , Silagem/análise , Solo/química
2.
J Sci Food Agric ; 99(14): 6649-6654, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31368529

RESUMO

BACKGROUND: This study evaluated the degradation of pyrrolizidine alkaloids (PAs) from eastern groundsel (Senecio vernalis) in grass silage prepared with different inoculants. Silages were produced from ryegrass with 230 g kg-1 dry matter (DM) content and mixed with eastern groundsel (9:1; w/w fresh matter basis) containing 5.5 g kg-1 DM PA. Treatments were: CON (untreated control), LP (3.0 × 105 cfu g-1 Lactobacillus plantarum DSMZ 8862/8866) or LBLC (7.3 × 104 cfu g-1 Lactobacillus buchneri LN40177 / Lactobacillus casei LC32909), and each of the treatments in combination with 30 g kg-1 molasses. Silages were prepared in glass jars and opened after 3, 10, and 90 days. Fermentation characteristics were determined and the PAs analyzed. RESULTS: Although the levels of fermentation acids differed between treatments, results indicated good quality of all silages during 90 days. Significant time (P < 0.001) and treatment (P < 0.001) effects were observed for PAs. Concentrations of senecionine and seneciphylline decreased with molasses, declined over time, and were negatively correlated with lactic, propionic, and butyric acid, or with lactic and butyric acid in case of seneciphylline. In all silages, seneciphylline and senecionine N-oxides were undetectable after 3 days, whereas senkirkine, the most abundant PA, remained stable. CONCLUSIONS: Silage prepared from grass contaminated with eastern groundsel still contained high PA levels, and was hence a potential health hazard. Molasses supplementation reduced concentrations of senecionine and seneciphylline, while the bacterial inoculants had no effect. Other potentially toxic PA metabolites were not analyzed in the present study and further research is needed. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ração Animal/análise , Manipulação de Alimentos/métodos , Lolium/química , Alcaloides de Pirrolizidina/química , Senécio/química , Silagem/análise , Ração Animal/microbiologia , Fermentação , Lactobacillus/metabolismo , Lactobacillus plantarum/metabolismo , Lolium/microbiologia , Melaço/análise , Alcaloides de Pirrolizidina/metabolismo , Alcaloides de Pirrolizidina/toxicidade , Senécio/toxicidade , Silagem/microbiologia
3.
Food Chem ; 295: 172-179, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174747

RESUMO

The effects of 10 and 20 days of fermentation followed by freeze-drying on the vitamin C and fatty acids contents, chemical conversions and overall chemical composition of Jerusalem artichoke were studied. Fermentation between the 10th and 20th days increased content of all saturated fatty acids and two of the four unsaturated fatty acids. The only fatty acid content that decreased was that of C18:1 cis 9 acid, which was suggested to be converted to other fatty acids. The experimental data, which were supported by energetical feasibility, suggested the reaction pathways of the mutual conversions of fatty acids and confirmed the decreased vitamin C content during fermentation. Discriminant modelling of the spectral data successfully distinguished the fresh, 10 days and 20 days fermented samples. The correlation of the spectral and reference data allowed to construct reference models for predicting the content of vitamin C and C18:1 cis 9 fatty acid.


Assuntos
Ácido Ascórbico/metabolismo , Ácidos Graxos/metabolismo , Helianthus/química , Silagem , Ácido Ascórbico/análise , Ácidos Graxos/análise , Fermentação , Análise de Alimentos/estatística & dados numéricos , Liofilização , Helianthus/metabolismo , Modelos Estatísticos , Silagem/análise , Espectrofotometria Infravermelho/estatística & dados numéricos
4.
World J Microbiol Biotechnol ; 35(5): 76, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31054017

RESUMO

Ensiling is one of the best known method to preserve fodder. The forage before ensiling intended for silages usually contains a low number of lactic acid bacteria (LAB), so it is necessary to apply starter cultures of selected strains. Traditionally, LAB starter cultures were applied to lower the pH by producing lactic acid and to inhibit the growth of undesirable epiphytic microorganisms by competing for nutrients. Nowadays, LAB inoculants have become an effective tool for creating microbial quality of silages by selecting species with extraordinary features. Epiphytic microflora characteristic of plant material used for the production of silages and the sources of undesirable microflora in the ensiling process are discussed. This review focuses on the most frequently studied issues related to the microbial silage quality and the recent trends in increasing the quality by LAB inoculants, with respect to recent directions for selecting types of modern LAB for inoculation. Among them, the main trends described were prevention of the growth of filamentous fungi and detoxification of mycotoxins by LAB inoculants, inhibition of yeast growth by LAB present in preparations and limiting the development of pathogenic bacterial microflora through controlled fermentation with the participation of LAB and the presence of their metabolites.


Assuntos
Microbiologia de Alimentos , Qualidade dos Alimentos , Ácido Láctico/metabolismo , Lactobacillales/fisiologia , Silagem/microbiologia , Biotecnologia , Fermentação , Conservação de Alimentos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Ácido Láctico/farmacologia , Lactobacillales/classificação , Lactobacillales/crescimento & desenvolvimento , Lactobacillus/fisiologia , Micotoxinas , Plantas/microbiologia , Silagem/análise , Leveduras/efeitos dos fármacos , Leveduras/crescimento & desenvolvimento
5.
Environ Sci Pollut Res Int ; 26(19): 19871-19878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31090007

RESUMO

Dissolved organic matter (DOM) extracted from wheat straw (SDOM) and cow manure (MDOM) were used to investigate their effects on the solubilization, uptake, and translocation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47). Partition coefficients (KDOC) of BDE 47 between water and the two types of DOM were measured by the solubility enhancement method. The uptake and translocation of BDE 47 by wheat plants were explored by hydroponic exposure experiments. In the range of 0 to 100 mg/L of DOM, the solubility of BDE 47 increased with increasing concentrations of DOM. The log [KDOC] values of BDE 47 in SDOM and MDOM solutions were 5.77 and 5.31, respectively. The log [KDOC] values of BDE 47 in SDOM solutions were higher than those in MDOM solutions, which might be ascribed to the higher content of aliphatic carbon and lower molecular weight of SDOM. The addition of DOM (50 mg/L) significantly increased the accumulation of BDE 47 in the shoots of wheat plants. Wheat straw DOM had greater effect than MDOM in enhancing the accumulation of BDE 47. This study demonstrated the potential risk of BDE 47 to plants resulting from DOM-facilitated transport or the changes in metabolic properties.


Assuntos
Éteres Difenil Halogenados/metabolismo , Substâncias Húmicas/análise , Resíduos Industriais/análise , Poluentes do Solo/metabolismo , Agricultura , Animais , Bovinos , Éteres Difenil Halogenados/química , Esterco/análise , Silagem/análise , Poluentes do Solo/química , Solubilidade , Triticum/química
6.
J Anim Sci ; 97(7): 3046-3055, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31125404

RESUMO

We examined the effects of replacing corn silage (CS) with reconstituted alfalfa hay (AH) or beet pulp (BP) in the starter diet on the nutrient intake and digestibility, growth performance, rumen fermentation characteristics, selected blood metabolites, and health status in Holstein dairy calves. Newborn female calves (n = 54; 3 d of age; 39.8 ± 1.36 kg BW) were assigned randomly to 3 groups receiving starter diets containing CS [10% dry matter (DM) basis; CS diet) and reconstituted AH (10% DM, RAH diet) or BP (10% DM; RBP diet). The starter diets had the same nutrient composition and DM content. The calves were weaned on day 50 and the study continued until day 70. Nutrient intake, body weight (at weaning and at the end of the study), daily weight gain, feed efficiency, and body measurements (including heart girth, withers height, body length, body barrel, hip height, and hip width) were not affected by the diet (P > 0.05). Health-related variables including rectal temperature, fecal score, and general appearance score were not influenced by the diets (P > 0.05). During the postweaning period, apparent total tract digestibility of DM, organic matter, and crude protein were higher for RBP (P = 0.001); however, digestibility of neutral detergent fiber was lower in RAH compared with CS or RBP (P = 0.001). Daily amount of nutrient digestibility did not change across the diets (P > 0.05). Rumen fluid pH and total volatile fatty acid concentration and profile were not different across the diets after weaning (P > 0.05). Calves fed RAH or RBP had higher blood concentration of ß-hydroxy butyric acid compared with CS only before weaning (P = 0.03). Blood albumin concentration was higher for RBP compared with CS or RAH during the preweaning (P = 0.006) and overall (P = 0.005) periods; however, it was lower for CS compared with RBP after weaning (P = 0.03). Concentration of other blood variables including glucose, blood urea N, total protein, and globulin did not change across the diets (P > 0.05). Calves, in general, were healthy, and replacing CS with RAH or RBP in the starter diet had no beneficial effect on their feed intake or growth performance indicating that CS and reconstituted AH or BP can be used interchangeably in dairy calf starter diets until 70 d of age, allowing dairy producers more choices in selecting the feed ingredients.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Fibras na Dieta/análise , Animais , Peso Corporal , Bovinos/sangue , Bovinos/crescimento & desenvolvimento , Indústria de Laticínios , Dieta/veterinária , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Feminino , Fermentação , Concentração de Íons de Hidrogênio , Medicago sativa , Distribuição Aleatória , Rúmen/metabolismo , Silagem/análise , Ganho de Peso , Zea mays
7.
J Dairy Sci ; 102(7): 6235-6241, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079907

RESUMO

The purpose of this study was to optimize the conditions of a previously proposed enzymatic method used to estimate in situ undigested neutral detergent fiber (uNDF). We used a multi-step enzymatic approach, in which samples were first solubilized in NaOH solutions as a preincubation (PreInc) phase. After rinsing, samples were incubated (24 h at 39°C) in a buffered solution (pH 6) containing hemicellulase, cellulase, and Viscozyme L enzymes (Sigma-Aldrich s.r.l., Milan, Italy), followed by incubation (24 h at 39°C) in a buffered solution (pH 5) containing xylanase. Two sets of experiments were performed: a calibration trial (that tested different PreInc conditions on 9 selected forages) and a validation trial (that verified the results by testing multiple samples of 6 different forage types and a group of fibrous by-products). In the calibration trial, samples (300 mg in Ankom F57 filter bags; Ankom Technology Corp., Fairport, NY) were preincubated at 39°C in a 0.1 M NaOH solution for 90, 180, or 240 min, or in 0.2, 0.5, 1.0, or 2.0 M NaOH solution for 90 min. The results indicated that the best PreInc method, in terms of intra-laboratory repeatability and estimation of reference in situ values, was 90 min in a 0.2 M NaOH solution. Thus, we used this PreInc condition to determine enzymatic uNDF of 257 samples in the validation trial. Although the selected method generally had good accuracy in predicting in situ uNDF, inconsistencies were noted for certain forage types. Overall, when enzymatic uNDF was used to predict the in situ uNDF of all samples, the regression was satisfactory (intercept = 7.098, slope = 0.920, R2 = 0.73). The regression models developed for alfalfa hays, corn silages, and small grain silages had also acceptable regression performances and mean square error of prediction (MSEP) values, and the main sources of MSEP variation were error due to incomplete (co)variation and random error. Even when R2 values were >0.70, the MSEP value of the regression model for grass hays was 149.55, and that for nonforage fibrous feeds was 155.16. Although enzymatic uNDF partially overestimated the in situ uNDF, particularly in grass silages, the proposed procedure seems to be promising for accurately predicting in situ uNDF, because it generally had good repeatability and provided satisfactory estimates of in situ uNDF.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Digestão , Animais , Celulase/metabolismo , Feminino , Glicosídeo Hidrolases/metabolismo , Itália , Medicago sativa/metabolismo , Complexos Multienzimáticos/metabolismo , Reprodutibilidade dos Testes , Rúmen , Silagem/análise , Zea mays/metabolismo
8.
J Dairy Sci ; 102(6): 5212-5218, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981480

RESUMO

Nitrogen concentrations in feeds, feces, milk, and urine samples were measured using 2 analytical methods following different drying procedures. Ten samples of corn silage, alfalfa silage, and concentrates collected from 2017 to 2018 at Krauss Dairy Research Center, The Ohio State University (Wooster), were used. A 4-d total collection digestion trial provided fecal samples from 10 cows (1 sample/cow), and another 10 cows were used to collect milk samples (1 sample/cow) and spot urine samples (1 sample/cow). Spot urine samples were acidified immediately to pH <3.0 when collected. Feed samples were oven dried (55°C) or lyophilized and analyzed using the Kjeldahl (KJ; copper sulfate as a catalyst) method and a combustion method (elemental analyzer; EA). Feces, urine, and milk samples were analyzed for N using the following methods: (1) fresh samples by KJ (referred to as wet KJ), (2) lyophilization (urine and milk for 8 h; feces for 120 h) followed by EA (LYO-EA), and (3) oven drying (milk and urine for 1 h; feces for 72 h at 55°C) followed by EA (OD-EA). Additionally, changes in N content of acidified urine at -20° over 180 d of storage were examined. Nitrogen concentrations in corn silage, alfalfa silage, and concentrates were greater for EA by 6.1, 4.8, and 8.3%, respectively, compared with KJ. Analysis of dried samples via EA compared with wet KJ resulted in lower fecal N content (27.8 vs. 29.3 g/kg of DM). Nitrogen concentration in fecal samples via KJ after lyophilization was lower by 5% compared with wet KJ but did not differ from LYO-EA, suggesting that N losses occurred during drying. Nitrogen determination with EA after drying of samples resulted in greater milk N (5.70 vs. 5.50 g/kg) and urinary N (9.16 vs. 9.06 g/kg) content compared with wet KJ. However, drying method (i.e., lyophilization vs. oven drying) did not affect N content of milk, urine, or feces. The use of EA resulted in lower percentage deviation of N content from duplicate sample assays for most samples (no difference was found for concentrate and fecal N), suggesting that EA was more precise than KJ. In conclusion, drying of feces caused N losses regardless of drying methods. For urine and milk samples, if drying is necessary (i.e., EA), oven drying at 55°C can be used rather than lyophilization. The N content was greater in feeds, milk, and urine when determined with EA versus KJ. In addition, N content in acidified and undiluted urine at -20° changed and should be analyzed within 90 d of storage. The results in the current study, however, did not account for laboratory-to-laboratory variation.


Assuntos
Ração Animal , Bovinos , Leite/química , Nitrogênio/análise , Animais , Dessecação , Dieta/veterinária , Fezes/química , Feminino , Lactação , Medicago sativa/química , Nitrogênio/urina , Silagem/análise , Zea mays/química
9.
J Dairy Sci ; 102(5): 4694-4703, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30852013

RESUMO

Wet sieving of manure can be used as a means of evaluating the nutrient utilization of diets by dairy cows. A commercially available system for this analysis (Nasco Digestion Analyzer, Nasco, Fort Atkinson, WI; NDA) employs principles of wet sieving for on-farm assessment. The objective of this study was to evaluate effects of diet manipulations and sampling techniques on fecal particle dry matter (DM), neutral detergent fiber (NDF), and starch distribution on NDA sieves. Eight Holstein heifers (means ± SD; age 18.4 ± 0.6 mo and BW 457.2 ± 27.3 kg), were randomly assigned to a split-plot 4 × 3 incomplete Latin square experimental design with 18-d periods (15 d of adaptation and 3 d of sampling). Treatment rations differed in forage quality (high ADF <35%, low ADF >35%) and fiber content (high NDF >45%, low NDF <40%) and were offered to heifers for ad libitum and restricted intakes. Diets were fed to allow 900 to 1,000 g/d of body weight gain and fed once daily. Fecal grab samples were collected 0, 6, 12, and 18 h after feeding all 3 d of the sampling period, and the remaining feces was collected in the manner of total fecal collection to represent a daily composite sample. After wet sieving of each sample using a NDA kit, the retained material on sieves was dried and analyzed for DM, NDF, and starch content. Sampling day and feeding regimen did not affect distributions of nutrients. Distributions of total fecal particle DM were greater for high forage quality and high fiber content diets (14.66 to 20.37% of sample DM). The NDF content in retained material decreased with decreasing sieve size (from 89.81 to 86.86%) and was not affected by forage quality and fiber content, whereas NDF retained on NDA (% DM) followed the same pattern as the retained particle DM weight. Starch content in retained material was below 0.5% in the majority of diets. Average retained fecal particle DM and NDF content varied depending on the time after feeding, resulting in the large differences between grab fecal samples and a daily total composite sample. However, average values of retained particle DM and NDF weight for all sampling time points were similar to ones from total daily composite sample.


Assuntos
Bovinos/fisiologia , Fibras na Dieta/administração & dosagem , Silagem/análise , Ração Animal , Animais , Peso Corporal , Indústria de Laticínios , Dieta/veterinária , Digestão , Fezes/química , Feminino , Distribuição Aleatória , Rúmen/metabolismo , Amido/análise
10.
J Anim Sci ; 97(4): 1852-1864, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30859194

RESUMO

Eight crossbred steers (BW 719.0 ± 65.0 kg) with ruminal and duodenal cannulae were used to examine the effect of trace mineral (TM) source on digestibility; ruminal and duodenal solubility of Cu, Zn, and Mn; and in vitro release of Cu, Zn, and Mn from the solid fraction of ruminal digesta. Experiment 1 determined the effect of TM source on DM and NDF digestibility in steers fed a corn silage and steam-flaked corn-based diet. Treatments consisted of 10 mg Cu, 20 mg Mn, and 30 mg Zn/kg DM from either sulfate TM (STM) or hydroxy TM (HTM) sources. Following a 14-d adaptation period, total fecal output was collected for 5 d. Dry matter digestibility was not affected by treatment, but NDF digestibility tended (P < 0.09) to be greater in HTM vs. STM supplemented steers. In Exp. 2, steers were fed a diet without supplemental Cu, Zn, or Mn for 19 d. Steers were then administrated a pulse dose of STM or HTM (2× the National Research Council requirements for Cu, Mn, and Zn) via the rumen fistula. Ruminal and duodenal samples were obtained at 2-h intervals starting at -4 and ending at 24 h relative to dosing. Ruminal soluble Cu and Zn concentrations were affected by treatment, time, and treatment × time. Soluble concentrations and percent soluble Cu and Zn in ruminal digesta increased (P < 0.05) above 0-h values for 10 h following dosing with STM, but not HTM. Concentrations of Cu and Zn in ruminal solid digesta were also affected by treatment, time, and treatment × time. Steers dosed with STM had greater (P < 0.05) solid digesta Cu concentrations at 2 and 4 h but lesser (P < 0.05) concentrations from 6 to 20 h post-dosing than those receiving HTM. Ruminal solid digesta Zn concentrations were greater (P < 0.05) in HTM vs. STM-dosed steers from 6 through 24 h post-dosing. Distribution of Mn in ruminal digesta was affected by TM source, but to a lesser extent than Zn and Cu. Duodenal soluble TM concentrations were variable and not affected by treatment. Binding strength of TM to ruminal solid digesta was estimated at 0, 6, and 12 h post-dosing using dialysis against chelating agents. The percentage of Cu and Zn released from ruminal solid digesta by dialysis against Tris-EDTA was greater (P < 0.05) at 12 h post-dosing from steers receiving HTM vs. STM. Results indicate that Cu and Zn from HTM have low solubility in the rumen and appear to be less tightly bound to ruminal solid digesta than Cu and Zn from STM.


Assuntos
Bovinos/fisiologia , Cobre/metabolismo , Suplementos Nutricionais , Oligoelementos/metabolismo , Zinco/metabolismo , Animais , Dieta/veterinária , Masculino , Rúmen/metabolismo , Silagem/análise , Solubilidade , Zea mays
11.
J Sci Food Agric ; 99(9): 4414-4422, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30859565

RESUMO

BACKGROUND: By-products of the food production chain are gaining importance as feedstuffs for ruminants. Alfalfa silage cake (AC) is an unexploited biorefinery by-product rich in fiber. The aim of this study was to test AC, using an in vitro rumen simulation technique (Rusitec), for its suitability as a fiber source for cattle. Three diets with similar crude protein (CP) content were formulated; they contained the biorefinery by-product AC, the original alfalfa silage (OA), or a fiber-rich hay. As fibrous feedstuffs are known to promote ruminal methanogenesis, we additionally tested a plant extract of Scrophularia striata (60 mg g-1 dry matter) for its methane mitigation and antimicrobial properties. RESULTS: Diets containing AC displayed lower nutrient degradability, with the largest difference in CP degradation (P < 0.001). Sequencing of microbial DNA revealed several effects of the diet and of the addition of S. striata extract, but no inhibitory effect on methanogens. Likewise, methane production, which, in general, is lower with AC and OA diets, was not inhibited by S. striata extract, while the short chain fatty acid (SCFA) profiles were unaffected. CONCLUSION: Although CP degradation of the AC diet was lower, degradation of the fiber fractions was similar among diets. According to the present results, AC can be used as fibrous feedstuff for ruminants. Supplementation with S. striata extract did not inhibit methane formation. © 2019 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Medicago sativa/metabolismo , Extratos Vegetais/metabolismo , Rúmen/metabolismo , Scrophularia/química , Silagem/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais/análise , Ácidos Graxos Voláteis/metabolismo , Medicago sativa/química , Metano/metabolismo , Valor Nutritivo , Extratos Vegetais/análise , Scrophularia/metabolismo , Resíduos/análise
12.
Trop Anim Health Prod ; 51(6): 1579-1584, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30820744

RESUMO

The objective of this study was to investigate the effect of four levels of molasses on chemical composition, in vitro digestibility, methane production and fatty acid profile of canola silages. A canola (Brassica napus var. Monty) crop was established in a small-scale agricultural farm and harvested 148 days after sowing. Four levels of molasses were tested with respect to the fresh weight (1.5 kg); these were 1% (CS-1), 2% (CS-2), 3% (CS-3) and 4% (CS-4) molasses, and 0% molasses (CS-0) was included as a control. A total of 45 microsilages were prepared using PVC pipes (4 in. of diameter × 20 cm of length), and the forage was compressed using a manual press. The effects of control and treatments were tested using the general linear model Y = µ + Ti + Eij. The linolenic acid (C18:3n3), palmitic acid (C16:0) and linoleic acid methyl ester (C18:2n6c) accounted for 30%, 21% and 10.5% of total fatty acids, respectively; the fermentation parameters and in vitro methane production were not affected (P > 0.05) by treatments; in vitro digestibility decreased significantly (P < 0.05) as the level of molasses increased. It was concluded that CS-4 improved the DM content by 9% and showed high content of linolenic acid methyl ester. The gross energy of canola silages could favour the oleic acid methyl ester.


Assuntos
Brassica napus , Metano/biossíntese , Melaço/análise , Silagem/análise , Animais , Digestão , Ácidos Graxos , Fermentação
13.
J Anim Sci ; 97(5): 2230-2244, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-30906949

RESUMO

The objective of this study was to determine the effects of different forms of hydrolyzable tannin [HT; source (chestnut, CN; tannic acid, TA); subunit (gallic acid, GA)] on apparent total-tract digestibility, methane (CH4) production, and nitrogen (N) utilization in beef cattle fed an alfalfa silage-based diet. Eight ruminally cannulated heifers with an initial BW of 480 ± 29.2 kg (mean ± SD) were used in a double 4 × 4 Latin square experiment. The experiment consisted of four 28-d periods (14-d adaptation, 14-d measurements) and a 7-d washout between periods. The animals received a basal diet with 19.8% CP (DM basis) content containing 75% alfalfa silage, 20% barley silage, and 5% supplement (DM basis) with or without different forms of HT. The dietary treatments were as follows: control (no HT), GA (1.5% of diet DM), TA (1.5% of diet DM), and CN (2% of diet DM). Animals were fed 95% of their ad libitum intake during the measurement phase. Total fecal excretion was collected for 4 d, CH4 was measured for 72 h using respiration chambers, and ruminal fermentation variables and plasma urea N (PUN) concentration were measured on 2 nonconsecutive days before and after feeding. The restricted DM (DMI; 10.79 ± 1.076 kg/d) and nutrient intakes did not differ (P ≥ 0.22) among treatments. Furthermore, apparent DM digestibility (60.3 ± 0.86%) was not affected (P = 0.20) by treatment, but CP digestibility decreased for TA and CN compared with control and GA treatments (63.1 vs. 69.0%; P < 0.001). Total VFA concentration tended (P = 0.089) to increase for GA compared with control and TA (134 vs. 125 and 126 mM) and intermediate for CN (129 mM). The PUN concentration was lower for all HT treatments compared with control (196 vs. 213 mg/L; P = 0.02). Both TA and CN increased the proportion of N excreted in feces and decreased the proportion in urine compared with control and GA (43.9% vs. 37.8% and 56.1% vs. 62.2%; respectively; P < 0.001). However, the proportion of urea N in urinary N decreased for all HT treatments compared with control (47.2% vs. 51.2%; P = 0.02). Also, GA tended to decrease CH4/DMI (20.4 vs. 22.3 g/kg DMI; P = 0.07) and decreased the proportion of GE intake emitted as CH4 (5.16 vs. 5.71%; P = 0.04) compared with control. Thus, among the different forms of HT applied to a high-protein alfalfa silage-based diet, both TA and CN had no effect on CH4 production, but decreased CP digestibility and shifted N excretion from urine to feces, whereas GA (i.e., HT subunit) decreased CH4 production and decreased the proportion of urea N in urinary N in beef cattle without affecting CP digestibility. Thus, feeding the HT subunit, GA, has the potential to decrease environment impact of ruminants (lower CH4 and ammonia emissions), without decreasing animal performance.


Assuntos
Bovinos/fisiologia , Ácido Gálico/farmacologia , Taninos Hidrolisáveis/farmacologia , Metano/metabolismo , Nitrogênio/metabolismo , Silagem/análise , Amônia/metabolismo , Animais , Dieta/veterinária , Dieta Rica em Proteínas , Suplementos Nutricionais , Fezes/química , Feminino , Fermentação , Hordeum , Medicago sativa , Ureia/sangue
14.
J Anim Sci ; 97(3): 1036-1041, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753619

RESUMO

Twelve adult beagle dogs (10.6 ± 1.4 kg) were fed extruded dog diets in which the starch sources were whole sorghum, sorghum flour, sorghum mill-feed, or an equal combination of rice, corn, and wheat. The experiment was conducted as a replicated Latin square design digestibility study. Estimates of fecal organic matter (OM), crude protein (CP), crude fat (CF), and gross energy (GE) outputs were determined by four methods: total fecal collection (TFC), chromic oxide (Cr2O3), titanium dioxide (TiO2), and acid insoluble ash (AIA). The correlation among the fecal output estimates by the four methods by partial correlation coefficients from the Error SSCP Matrix (Pearson) were considered significant at P < 0.05. The external markers, Cr2O3 and TiO2, had a higher (P < 0.05) OM fecal output Pearson correlation to TFC than the intrinsic marker AIA (R = 0.931 for Cr2O3 vs. TiO2; R = 0.559 for TFC vs. Cr2O3; R = 0.592 for TFC vs. TiO2; R = 0.291 for AIA vs. TFC). Interestingly, TiO2 highly correlated (P < 0.05) to Cr2O3 (R = 0.93 for OM), and was also correlated highly to TFC and AIA. The study suggests that TiO2 may be a preferred marker to estimate fecal output in dogs vs. Cr2O3. The use of AIA represents a potential option for determining digestibility for diets in which external markers are impractical.


Assuntos
Compostos de Cromo/metabolismo , Digestão , Cães/fisiologia , Silagem/análise , Titânio/metabolismo , Animais , Biomarcadores/metabolismo , Dieta/veterinária , Fezes/química , Feminino , Farinha , Masculino , Oryza , Sorghum , Triticum , Zea mays
15.
J Anim Sci ; 97(4): 1819-1827, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30753570

RESUMO

The objective of this study was to evaluate the effect of cinnamaldehyde, on feed intake, rumen fermentation, nutrient digestibility, milk yield, and components in lactating dairy cows. Six lactating Holstein dairy cows (3 ruminally cannulated and 3 noncannulated) averaging 263 ± 41 d in milk (DIM) and 754 ± 45 kg of BW at the beginning of the study were used. Cows were randomly assigned to 1 of 3 treatments in a replicated 3 × 3 Latin square design with 19 d periods (14 d for diet adaptation and 5 d for sample collection). Treatments were 0, 2, or 4 mg/kg of BW of cinnamaldehyde. Cinnamaldehyde was mixed with 40 g of corn meal and top-dressed onto the total mixed ration (TMR). Diet was fed as a TMR and contained 37% corn silage, 18.5% mixed-mostly grass silage, 24.5% energy supplement, 16.5% protein supplement, and 3.5% vitamin and mineral mix on a DM basis. The dietary nutrient composition averaged 15.1% CP, 37.8% NDF, and 24.7% ADF. Cows were fed and milked twice daily. No differences were observed for DMI (mean = 24.6 kg/d), milk yield (mean = 28.4 kg/d), 3.5% fat-corrected milk (FCM; mean = 30.6 kg/d), and 3.5% energy-corrected milk (ECM; mean = 30.7 kg/d). The dose of cinnamaldehyde did not have any effect on milk components, rumen fermentation, or pH. There were no differences in nutrient digestibility, but there was a trend for a quadratic effect for DM digestibility (P = 0.09): 74.4%, 76.3%, and 73.7% for treatments 0, 2, and 4 mg/kg of BW of cinnamaldehyde, respectively. A linear effect (P = 0.02) and a quadratic effect (P < 0.02) observed for urinary urea N and a quadratic effect (P = 0.03) for allantoin and total purine derivatives with the 2 mg/kg treatment being the lesser value. These data suggest that cinnamaldehyde at these dosages may have an antimicrobial effect in the rumen as suggested by a lesser concentration of urinary total purine derivatives. Overall, supplementing lactating dairy cows with cinnamaldehyde had no effect on feed intake, milk yield, or milk components. However, it appears that cinnamaldehyde has a negative effect on rumen microbial protein synthesis as suggested by the reduced concentration of urinary purine derivatives.


Assuntos
Acroleína/análogos & derivados , Ração Animal/análise , Bovinos/fisiologia , Suplementos Nutricionais , Leite/metabolismo , Acroleína/farmacologia , Animais , Nitrogênio da Ureia Sanguínea , Dieta/veterinária , Digestão/efeitos dos fármacos , Feminino , Fermentação/efeitos dos fármacos , Lactação/efeitos dos fármacos , Nutrientes/metabolismo , Poaceae , Distribuição Aleatória , Rúmen/metabolismo , Silagem/análise , Zea mays
16.
Anim Sci J ; 90(4): 513-522, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30773737

RESUMO

The objective of this study was to examine the fermentation quality and aerobic stability of mulberry (Morus alba L.) silage prepared with lactic acid bacteria (LAB) and propionic acid (PA). The selected LAB strains Lactobacillus (L.) plantarum LC365281 (L1) and L. brevis LC365282 (L2), and commercial inoculant strains L. plantarum Gaofuji (GF) and L. buchneri Fresh (FR), and PA were used as additives for silage preparation. Silage treatments were designed as control, L1, L2, GF, FR, PA, PA + L1, PA + L2, PA + GF, or PA + FR. After 30 days of ensiling, the fermentation quality of silages treated with PA + L1 was improved, with a lower (p < 0.05) pH and NH3 -N content than those of other treatments. During the aerobic exposure, the PA + LAB-treated silages displayed an aerobic stability with stable pH value and lactic acid content. The results confirm that L. plantarum L1 and PA were the best additive combination for ensiling mulberry.


Assuntos
Fermentação , Lactobacillus brevis , Lactobacillus plantarum , Morus , Propionatos , Silagem , Aerobiose , Compostos de Amônio/análise , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Silagem/análise , Fatores de Tempo
17.
J Anim Sci ; 97(5): 2188-2201, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-30796804

RESUMO

Effects of whole-crop barley and grass silages harvested at different maturity stages, with or without protein supplementation, on intake, in vivo digestibility, feces characteristics, and protein utilization in wethers were evaluated. Whole-crop barley silage harvested at heading stage (BH) and at medium milk stage (BM), grass silage (GE) taken at the flag leaf-early heading stage, and grass silage (GL) taken at medium-late heading stage were fed to eight wethers in two 4 × 4 Latin squares. Wethers in one square were fed supplementary rapeseed meal. Experimental periods lasted for 4 wk and wethers were fed ad libitum during the first 3 wk, with intake recorded during the third week. During the fourth week, wethers were fed 80% of ad libitum, and feces and urine were collected during the last 4 d. The GE and BH diets had greater (P < 0.05) in vivo apparent digestibility of DM and its nutrients, lower proportion of fecal particle DM (PDM) with a greater proportion of small particles compared with GL and BM diets, respectively. The GE diet had greater (P < 0.001) in vitro OM digestibility and in vivo digestibility of OM and fibre, resulting in a smaller (P < 0.001) proportion of PDM with a greater (P < 0.001) proportion of small particles compared with the other diets. In vivo NDF digestibility was negatively related to fecal PDM across forage types (R2 = 0.91, RMSE = 2.55). The GE silage had greater CP concentration, and animals fed the GE diet had greater intake of CP (P < 0.001) and sum of the degradable CP fractions A, B1, and B2 (P < 0.01), resulting in greater (P < 0.05) urinary nitrogen (N) excretion than when fed any of the other diets and a lower (P < 0.05) N retention compared with BH and BM diets. Microbial N supply tended to increase when animals were fed the BH diet (P = 0.10) and when rapeseed meal was added to the forages (P = 0.08). Increased N intake (P = 0.008) by rapeseed meal supplementation increased urinary N excretion in gram per day (P = 0.05). The strong relationship between in vivo NDF digestibility and fecal PDM indicates potentials for using PDM as a cheap method to predict NDF digestibility. Early harvest of the forages improved in vivo digestibility of nutrients, resulting in less fecal PDM with a greater proportion of small particles compared with late harvest within forage type. However, wethers fed the GE diet had greater urinary N losses compared with wethers fed the GL diet but this effect of maturity was absent when fed whole-crop barley silage.


Assuntos
Fibras na Dieta/metabolismo , Hordeum , Poaceae , Ovinos/fisiologia , Silagem/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Digestão , Ingestão de Alimentos , Fezes/química , Masculino
18.
J Dairy Sci ; 102(3): 2266-2274, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639005

RESUMO

The objective of this study was to evaluate the effects of supplementing xylanase on production performance, nutrient digestibility, and milk fatty acid profile in high-producing dairy cows consuming corn silage- or sorghum silage-based diets. Conventional corn (80,000 seeds/ha) and brown midrib forage sorghum (250,000 seeds/ha) were planted, harvested [34 and 32% of dry matter (DM), respectively], and ensiled for more than 10 mo. Four primiparous and 20 multiparous Holstein cows were randomly assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments and 19-d periods. Treatment diets consisted of (1) corn silage-based diet without xylanase, (2) corn silage-based diet with xylanase, (3) sorghum silage-based diet without xylanase, and (4) sorghum silage-based diet with xylanase. The xylanase product was supplemented at a rate of 1.5 g of product/kg of total DM. Corn silage had higher concentrations of starch (31.2 vs. 29.2%), slightly higher concentrations of crude protein (7.1 vs. 6.8%) and fat (3.7 vs. 3.2%), and lower concentrations of neutral detergent fiber (36.4 vs. 49.0%) and lignin (2.1 vs. 5.7%) than sorghum silage. Xylanase supplementation did not affect DM intake, milk yield, milk fat percentage and yield, milk protein percentage and yield, lactose percentage and yield, and 3.5% fat-corrected milk yield. Cows consuming corn silage-based diets consumed 13% more DM (28.8 vs. 25.5 kg/d) and produced 5% more milk (51.6 vs. 48.9 kg/d) than cows consuming sorghum silage-based diets. Milk from cows consuming sorghum silage-based diets had 16% greater fat concentrations (3.84 and 3.30%) than milk from cows consuming corn silage-based diets. This resulted in 8% greater fat yields (1.81 vs. 1.68 kg/d). Silage type did not affect milk protein and lactose concentrations. Xylanase supplementation did not affect nutrient digestibility. Cows consuming corn silage-based diets showed greater DM (77.3 vs. 73.5%), crude protein (78.0 vs. 72.4), and starch (99.2 vs. 96.5%) digestibilities than cows consuming sorghum silage-based diets. In conclusion, xylanase supplementation did not improve production performance when high-producing dairy cows were fed corn silage- or sorghum silage-based diets. In addition, production performance can be sustained by feeding sorghum silage in replacement of corn silage.


Assuntos
Bovinos/fisiologia , Digestão , Endo-1,4-beta-Xilanases/metabolismo , Lactação , Leite/química , Silagem/análise , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Endo-1,4-beta-Xilanases/administração & dosagem , Ácidos Graxos/metabolismo , Feminino , Nutrientes/fisiologia , Silagem/classificação , Sorghum/química , Zea mays/química
19.
J Dairy Sci ; 102(3): 2075-2084, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30612798

RESUMO

Formulating diets with high inclusion rates of a feed that provides necessary nutrients at lower-than-market prices for those nutrients should increase income over feed costs if the feed is not detrimental to yields of milk and milk components. The objective of this study was to determine whether cows fed a diet composed of approximately 53% corn silage, 44% corn milling product (68% dry matter, 21% crude protein, 37% neutral detergent fiber, and 9% starch) and 3% minerals (CMP) would have similar productivity as cows fed a control diet of predominantly corn silage, alfalfa silage, corn grain, and soybean meal. Based on the National Research Council (2001) dairy model, the CMP diet was inadequate in metabolizable methionine and extremely low in metabolizable lysine. A third treatment (CMP+AA) was the same as the CMP diet but was supplemented with rumen-protected lysine and methionine. Twenty-one Holstein cows were used in a replicated Latin square (28-d periods) design to evaluate production responses to the 3 diets. Diets were formulated to contain the same concentration of net energy for lactation and metabolizable protein (MP) based on the National Research Council model, but diets with CMP contained more neutral detergent fiber (38.3 vs. 31.4%) and less starch (21.6 vs. 30.5%) than the control diet. Lysine as a percent of MP was 6.5, 6.0, and 6.8 for the control, CMP, and CMP+AA diets, respectively, and methionine was 1.8, 1.8, and 2.3% of MP, respectively. Dry matter intake was not affected by diet (24.3 kg/d), but milk yield was lower for cows fed either CMP diet than for those fed control (36.0 vs 38.1 kg/d). Milk fat concentrations were normal and not affected by diet (3.7%). Milk protein concentration was greater for cows fed CMP+AA than for cows fed the other 2 treatments (3.19 vs. 3.11%); however, milk protein yield was greatest for cows fed the conventional diet. The concentration of methionine in plasma was significantly greater for cows fed CMP+AA than for cows fed the other diets. Plasma lysine concentrations were greater for cows fed the conventional diet than for those fed the other 2 diets. Plasma concentrations of several essential AA were lower for cows fed either CMP diet. Based on calculated energy balance, diets contained similar concentrations of net energy for lactation, but cows fed CMP diets partitioned more energy toward body energy reserves than did control cows, perhaps because supply of specific AA limited milk synthesis.


Assuntos
Lisina/metabolismo , Metionina/metabolismo , Leite/química , Zea mays/química , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Lisina/administração & dosagem , Metionina/administração & dosagem , Distribuição Aleatória , Silagem/análise
20.
J Dairy Sci ; 102(3): 2085-2093, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30612804

RESUMO

Although the inclusion of fat has reduced methane production in ruminants, relatively little research has been conducted comparing the effects of source and profile of fatty acids on methane production in lactating dairy cows. A study using 8 multiparous (325 ± 17 DIM; mean ± SD) lactating Jersey cows was conducted to determine effects of feeding canola meal and lard versus extruded byproduct containing flaxseed as a high-C18:3 fat source on methane production and diet digestibility in late-lactation dairy cows. A crossover design with 32-d periods (28-d adaptation and 4-d collections) was used to compare 2 different fat sources. Diets contained approximately 50% forage mixture of corn silage, alfalfa hay, and brome hay; the concentrate mixture changed between diets to include either (1) a conventional diet of corn, soybean meal, and canola meal with lard (control) or (2) a conventional diet of corn and soybean meal with an extruded byproduct containing flaxseed (EXF) as the fat source. Diets were balanced to decrease corn, lard, and canola meal and replace them with soybean mean and EXF to increase the concentration of C18:3 (0.14 vs. 1.20% of DM). Methane production was measured using headbox-style indirect calorimeters. Cattle were restricted to 95% ad libitum feed intake during collections. Milk production (17.4 ± 1.04 kg/d) and dry matter intake (15.4 ± 0.71 kg/d) were similar among treatments. Milk fat (5.88 ± 0.25%) and protein (4.08 ± 0.14%) were not affected by treatment. For methane production, no difference was observed for total production (352.0 vs. 349.8 ± 16.43 L/d for control vs. EXF, respectively). Methane production per unit of dry matter intake was not affected and averaged 23.1 ± 0.57 L/kg. Similarly, methane production per unit of energy-corrected milk was not affected by fat source and averaged 15.5 ± 0.68 L/kg. Heat production was similar, averaging 21.1 ± 1.02 Mcal/d. Digestibility of organic matter, neutral detergent fiber, and crude protein was not affected by diet and averaged 69.9, 53.6, and 73.3%, respectively. Results indicated that increasing C18:3 may not affect methane production or digestibility of the diet in lactating dairy cows.


Assuntos
Ração Animal , Dieta/veterinária , Lactação/efeitos dos fármacos , Metano/biossíntese , Ácido alfa-Linoleico/farmacologia , Animais , Bovinos , Fibras na Dieta/metabolismo , Suplementos Nutricionais , Ácidos Graxos/metabolismo , Feminino , Leite/química , Silagem/análise , Soja/metabolismo , Zea mays/metabolismo
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