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1.
Animal ; 15(3): 100151, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33573935

RESUMO

Dairy calves may benefit from extending the duration of feeding transition milk (TM; the subsequent two to six milkings after parturition) to enhance performance and health during early life. The objective of this study was to assess the effect of replacing pasteurized waste milk (non-saleable milk containing antibiotic and/or drug residues) with pasteurized TM for 3 weeks on the growth performance and health of dairy calves. A total of 84 healthy newborn female Holstein calves were blocked by birth order and assigned randomly to 4 treatment groups with partial replacement of pasteurized waste milk by TM (second milkings after parturition) at 0 (0 l/day TM + 6 l/day milk), 0.5 (0.5 l/day TM + 5.5 l/day milk), 1 (1 l/day TM + 5 l/day milk), or 2 l (2 l/day TM + 4 l/day milk) for a 21-day period. From day 22 onward, all calves were fed individually with 6 l/day pasteurized waste milk. Calves were weaned on day 60 and monitored until day 90 of the study. Liquid feed DM intake (DMI) was increased with increasing levels of TM (P = 0.001). Starter feed DMI and total DMI (liquid feed DMI + starter feed DMI) were not affected by the treatment effect. Calves were fed 2 l/day TM gained more BW compared with those in the control group during the postweaning and overall periods. The average daily gain tended (P = 0.06) to be higher in calves fed 2 l/day TM compared with calves fed 0 (+ 65 g/day), 0.5 (+ 53 g/day), or 1 (+ 76 g/day) l/day TM during the preweaning period. Daily weight gain was also higher in calves fed 2 l/day TM compared with calves in the control group during the postweaning (+ 137 g/day; P = 0.04) and overall (+89 g/day; P < 0.01) periods, respectively. Calves fed 2 l/day TM had a higher feed efficiency compared with calves in the control group during all studied periods. The calves fed TM2 had a lower chance of having diarrhea compared with other treatment groups. Duration but not the frequency of diarrhea was lower in calves fed TM2 vs TM0 (2.5 vs 4.2days; P = 0.03). In general, partial replacement of waste milk with TM (2 l/day) may be recommended to feed dairy calves at an early stage of life to support a higher growth rate and health benefits.


Assuntos
Ração Animal , Leite , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Diarreia/prevenção & controle , Diarreia/veterinária , Dieta/veterinária , Feminino , Desmame
2.
J Dairy Sci ; 103(9): 8130-8142, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32684449

RESUMO

The objective of this study was to determine the effect of partial replacement of whole milk with colostrum on the growth performance and health status of Holstein dairy calves. Neonatal heifer calves (n = 144; 2 d of age; 39.3 ± 0.82 kg of body weight, BW; mean ± SE) were assigned randomly to 3 groups with partial replacement of pasteurized whole milk with pasteurized colostrum at 0 (C0; 0 kg/d of colostrum + 5 kg/d of whole milk), 350 g (C350; 0.350 kg/d of colostrum + 4.650 kg/d of whole milk), or 700 g (C700; 0.700 kg/d of colostrum + 4.300 kg/d of whole milk) for 14 d; there were no refusals of liquid feed. From d 15 onward, the calves were fed with 5 kg/d of pasteurized whole milk, weaned on d 61, and monitored until d 81 of life. Throughout the study, the calves had free access to fresh clean water and calf starter. Partial replacement of whole milk with colostrum increased liquid feed dry matter intake (DMI) but decreased milk DMI; however, intakes of starter DMI, total DMI, metabolizable energy, crude protein, and ether extract were not affected by treatments. Overall, the C700 calves recorded greater weaning weight, final BW, heart girth change, feed efficiency, and average daily gain (ADG). The calves fed milk had a higher chance of having rectal temperature ≥39.4°C and general appearance score ≥2 compared with those receiving colostrum in their milk. Diarrhea was more prevalent in C0 versus C700 calves. The occurrence of pneumonia tended to be higher in milk-fed calves compared with C350 and C700 animals. Colostrum feeding resulted in fewer days with a rectal temperature ≥39.4°C, general appearance ≥2, diarrhea, and pneumonia. We computed Cliff's delta (effect sizes) of the extended colostrum feeding (C350 vs. C0, C700 vs. C0, and C700 vs. C350) on starter and milk DMI, ADG, BW, and feed efficiency. In C350 calves, the effect sizes (Cliff's delta) for milk DMI, ADG, BW, and feed efficiency were positive and small, but negative in C700 calves. Compared with C350 treatment, C700 treatment resulted in greater final BW with moderate effect size. Positive and moderate effects of feeding colostrum (C700 vs. C0) were observed on postweaning ADG and final BW. The findings showed that the inclusion of 700 g of colostrum in 5 kg of milk may be beneficial to the growth and health of dairy calves.


Assuntos
Doenças dos Bovinos/prevenção & controle , Colostro/imunologia , Indústria de Laticínios/métodos , Diarreia/veterinária , Dieta/veterinária , Crescimento/imunologia , Pneumonia/veterinária , Ração Animal/normas , Animais , Animais Recém-Nascidos , Peso Corporal , Bovinos , Diarreia/prevenção & controle , Feminino , Leite , Pasteurização , Pneumonia/prevenção & controle , Gravidez , Distribuição Aleatória , Desmame
3.
Animal ; 13(11): 2501-2509, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31062676

RESUMO

Adding corn silage (CS) instead of alfalfa hay (AH) to the finely ground starter diet would improve calf performance if feed intake or feed efficiency is increased. We investigated the effects of replacing AH with CS in the starter diet on nutrient intake, digestibility, growth performance, rumen fermentation and selected blood metabolites in Holstein calves. Newborn male calves (n = 30; 3 days of age; 40.2 ± 1.28 kg BW) were assigned randomly to three groups receiving starter diets containing chopped AH (10% dry matter (DM) basis; AH diet), CS (10% DM, CS diet) or their combination (each at 5% level; AHCS diet). The starter diets had the same nutrient composition but differed in DM content (91.2%, 87.5% and 83.8% for AH, AHCS and CS, respectively). The calves were weaned on day 50, and the study continued until day 70. Nutrient intake, BW (at weaning and at the end of the study) and body measurements were not affected by the diet. During the post-weaning period, average daily gain tended to be greater on CS than on AH diet. Feed efficiency was greater in CS than in AH or AHCS calves during the post-weaning period. Digestibility of neutral detergent fiber was greater in AHCS and CS compared with AH during the post-weaning period. Concentration and profile of volatile fatty acids and ruminal fluid pH were not affected by the diet. Replacing AH with CS in the starter diet had no effect on feed intake, growth performance and general health of the calves. These results indicate that AH and CS can be used interchangeably in dairy calf starter diets until 70 days of age, allowing dairy producers more choices in selecting the feed ingredients.


Assuntos
Bovinos/fisiologia , Medicago sativa , Silagem/análise , Zea mays , Ração Animal/análise , Animais , Bovinos/sangue , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Fibras na Dieta/metabolismo , Ácidos Graxos Voláteis/sangue , Fermentação , Masculino , Nutrientes , Distribuição Aleatória , Rúmen/metabolismo , Desmame
4.
J Vet Intern Med ; 29(2): 714-20, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25641234

RESUMO

OBJECTIVE: To evaluate the effect of orally administered cisapride, bethanechol, and erythromycin on the absorption of colostral IgG in dairy calves. ANIMALS: Twenty-four healthy neonatal Holstein-Friesian calves. PROCEDURES: Calves were randomly assigned to one of the following treatments: 0.9% NaCl solution (2 mL, p.o.; negative control); erythromycin lactobionate (20 mg/kg BW, p.o.; anticipated to be a positive control); cisapride (0.5 mg/kg BW, p.o.); bethanechol chloride (0.5 mg/kg BW, p.o.). Calves were fed 3 L of pooled bovine colostrum containing acetaminophen (50 mg/kg) by suckling and oroesophageal intubation 30 minutes after each treatment was administered. Jugular venous blood samples were obtained periodically after the start of feeding and plasma total IgG, protein, acetaminophen, and glucose concentrations determined. Abomasal emptying rate was assessed by the time to maximal plasma acetaminophen concentration. RESULTS: Oral administration of cisapride facilitated the absorption of colostral IgG and protein. The effect of cisapride on abomasal emptying rate could not be evaluated because cisapride appeared to interfere with acetaminophen metabolism. Based on the total IgG and total protein concentration-time relationships, the beneficial effects of cisapride appeared to occur early after oral administration and were transient. CONCLUSIONS AND CLINICAL IMPORTANCE: Additional studies appear indicated to characterize the effect of cisapride dose on the magnitude and duration of its effect on facilitating the absorption of colostral IgG and protein. Identification of a nonantimicrobial method for increasing abomasal emptying rate, such as cisapride, will potentially provide a practical and effective method for facilitating transfer of passive immunity in colostrum-fed dairy calves.


Assuntos
Betanecol/farmacocinética , Bovinos/fisiologia , Cisaprida/farmacocinética , Eritromicina/farmacocinética , Imunoglobulina G/metabolismo , Acetaminofen/sangue , Acetaminofen/farmacocinética , Administração Oral , Animais , Animais Recém-Nascidos , Glicemia , Colostro/química , Colostro/metabolismo , Fármacos Gastrointestinais/farmacocinética , Trânsito Gastrointestinal , Glucose/metabolismo , Masculino , Parassimpatomiméticos/farmacocinética , Parassimpatomiméticos/farmacologia
5.
J Sep Sci ; 34(2): 233-40, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21246730

RESUMO

Essential fatty acids were extracted from Echium amoenum (Boraginaceae) seed oil via supercritical carbon dioxide and the results were compared with conventional Soxhlet method as the base case of 100% recovery. The response surface methodology was used to optimize the effective extraction parameters. The chemical composition of recovered oil was analyzed by polar and non-polar gas chromatograph-flame ionization detector columns. The experimental results indicated that echium seed contained 25 wt% oil and the maximum extraction oil recovery of 92% was obtained via supercritical CO(2) at optimal operating conditions (43°C, 280 bar, 1.5 mL/min, 25 min static time and 130 min dynamic time). At similar operating conditions, applying 2.5 and 5 mol% ethanol as a modifier enhanced the recovery to 96 and 112%, respectively. The results showed that supercritical fluid extraction is a viable technique for separation of constituents such as γ-linolenic acid (7-8%), palmitic acid (6-7%), stearic acid (3-4%), oleic acid (12-13%), linoleic acid (19-20%), α-linolenic acid (40-41%) and stearidonic acid (8-9%) from Boraginaceae.


Assuntos
Boraginaceae/química , Cromatografia com Fluido Supercrítico/métodos , Ácidos Graxos Insaturados/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ácido gama-Linolênico/isolamento & purificação , Ácidos Graxos Insaturados/análise , Extratos Vegetais/análise , Ácido gama-Linolênico/análise
6.
Pak J Biol Sci ; 10(14): 2389-95, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19070162

RESUMO

Experiments were carried out to study the effect of feeding Megalac, calcium soaps of fatty acids (protected fat), on reproduction and lactation of sheep. In the first experiment, 20 Ghezel and 20 Mehraban cyclic fertile ewes (4-5 years old) were randomly allotted to 4 groups. The control group was fed with a balanced ration and the other groups received the same diet as well as a daily allowance of 40 g non-protected fat (NP), 40 g protected fat (LP), or 80 g (HP) protected fat. The ewes were fed with their respective rations for one cycle length. Blood samples were collected and analyzed for progesterone (P4), cholesterol (CHOL), High Density Lipoproteins (HDL), Low Density Lipoproteins (LDL) and triacylglycerols (TG). The ewes were slaughtered on their next estrous period and the size and number of follicles in ovaries were recorded. There were no significant effects of feeding fat on ovarian weights, cycle length and follicular numbers in each class, or on the size of the largest follicle. Serum concentrations of P4, CHOL, TG and HDL were greater for HP ewes as compared with the control ewes (p<0.05). In the second experiment, effects on lactation and lamb performance of feeding protected fat during mating, late gestation and early lactation were studied in Mehraban ewes. Milk and fat yields on day 25 of lactation were significantly increased by feeding protected fat. Protected fat resulted in lower weight loss in ewes and a higher lamb birth weight. Average daily weight gain of lambs from birth to day 60 and the weaning weight of lambs were increased by feeding protected fat (p<0.05). In conclusion, calcium soaps of fatty acids increased serum P4 between days 10 to 14 of the cycle which may be beneficial to early pregnancy maintenance. Protected fat seemed to have a beneficial effect on milk yield, fat yield, lamb daily gain, lamb birth weight and ewe weight loss.


Assuntos
Cálcio/química , Ácidos Graxos/administração & dosagem , Lactação , Reprodução , Animais , Estro , Ácidos Graxos/química , Feminino , Lipídeos/sangue , Folículo Ovariano/efeitos dos fármacos , Progesterona/sangue , Ovinos
7.
Anal Bioanal Chem ; 382(2): 444-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15838616

RESUMO

A sensitive, selective and simple preconcentration method for ultra-trace gold determination has been developed that uses naphthalene-methyltrioctyl ammonium chloride (Aliquat 336s) as an adsorbent. Gold, in the form of AuCl4-, was retained by the adsorbent in the column at a flow rate of 1 ml min(-1). After filtration, the solid mass consisting of the gold complex and naphthalene was dissolved out of the column with 5 ml of N,N-dimethylformamide (DMF), and the metal was then determined by atomic absorption spectrometry. In the initial solution, the calibration graph of absorbance versus gold concentration was found to be linear in the range 0.5-150 ng ml(-1) Au(III) with r=0.997 (n=9), and the 3 s detection limit was 0.428 ng ml(-1). The relative standard deviation for eight replicate measurements of 20 microg of gold was 2.14%. Preconcentration factors of 390 and 650 were achieved using 5 ml and 3 ml of DMF, respectively. The proposed method was successfully applied to the determination of gold in wastewater, processed pool water, slurry pool water, and raw well-water from the Moteh gold mine, and synthetic samples.

8.
Anal Bioanal Chem ; 378(6): 1659-65, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15214432

RESUMO

A sol-gel electrode and a coated wire ion-selective poly(vinyl chloride) membrane, based on thiosemicarbazone as a neutral carrier, were successfully developed for the detection of Cu (II) in aqueous solutions. The sol-gel electrode and coated electrode exhibited linear response with Nernstian slopes of 29.2 and 28.1 mV per decade respectively, within the copper ion concentration ranges 1.0 x 10(-5) - 1.0 x 10(-1) M and 6.0 x 10(-6) - 1.0 x 10(-1) M for coated and sol-gel sensors. The coated and sol-gel electrodes show detection limits of 3.0 x 10(-6) and 6.0 x 10(-6) M respectively. The electrodes exhibited good selectivities for a number of alkali, alkaline earth, transition and heavy metal ions. The proposed electrodes have response times ranging from 10-50 s to achieve a 95% steady potential for Cu2+ concentration. The electrodes are suitable for use in aqueous solutions over a wide pH range (4-7.5). Applications of these electrodes for the determination of copper in real samples, and as an indicator electrode for potentiometric titration of Cu2+ ion using EDTA, are reported. The lifetimes of the electrodes were tested over a period of six months to investigate their stability. No significant change in the performance of the sol-gel electrode was observed over this period, but after two months the coated wire copper-selective electrode exhibited a gradual decrease in the slope. The selectivity of the sol-gel electrode was found to be better than that of the coated wire copper-selective electrode. Based on these results, a novel sol-gel copper-selective electrode is proposed for the determination of copper, and applied to real sample assays.

9.
Anal Bioanal Chem ; 375(8): 1212-20, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12677346

RESUMO

Heavy alkylbenzene (HAB) is one of the by-products when producing linear alkylbenzene (LAB). Identification of the fine structures of HAB is difficult because of its complex structure and high boiling point. The gas chromatography/mass spectrometry (GC/MS) technique with a short glass capillary column is the best method applicable to analysis of high-boiling and thermally labile compounds. The column efficiency is evaluated on the basis of Van Deemter curves. The experimental results show that the reduction in the optimum column efficiency for a short glass capillary column occurs along with a reduction in effective theoretical plates. A second important result is that the shift in the value of the flow velocity is related to the optimum point in height equivalent theoretical plate (HETP). The flow velocity is higher than that of conventional gas chromatography(GC). The optimized conditions were used to analyse HAB produced through the hydrogen fluoride (HF) alkylation process. The results show acceptable relative separation of a product in an extended boiling point range. The optimized conditions were also used to analyse three other special samples supplied by BASF company's AlCl(3 )alkylation process and to approve the previous structures. The results also show that HAB from Iran Chemical Industries Investment Company (ICIIC) produced through LAB complex consists of an additional part and has more linearity than the other three samples of HAB obtained from BASF.

10.
J Pharm Biomed Anal ; 24(5-6): 1037-48, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11248499

RESUMO

The objective of this study was to investigate the theoretical feasibility of using supercritical fluid extraction of Mannitol from plane tree leaf as an alternative technology in the pharmaceutical industry. Simulation of an extraction column using dense liquid and supercritical carbon dioxide was modeled involving partial differential equations, using orthogonal collocation on finite elements. The important solvent extraction parameters such as the partition coefficient, mass transfer coefficient, dispersion coefficient, molecular diffusion and extraction efficiency (the amount of Mannitol extracted versus the amount of solvent used) were investigated as a function of the dimensionless Reynold's and Peclet numbers in order to optimize the extraction column geometry and the carbon dioxide operating conditions. The results of this study demonstrated that supercritical extraction is a viable technique for Mannitol production and that the process conditions for a large commercial extraction system do not require a high temperature in order to obtain a high extraction efficiency. However, at low pressures, the solubility of Mannitol in carbon dioxide would limit the success of the extraction process and at very high pressures the extraction technique may not be economically feasible. To investigate the authenticity of the mathematical model, the experimental data for the desorption of hexachlorobenzene from soil was compared with the theoretical results of this research. The model is able to predict the experimental data quite well without any adjustable parameters.


Assuntos
Cromatografia/métodos , Manitol/isolamento & purificação , Árvores/química , Manitol/química , Folhas de Planta/química , Pressão , Solubilidade , Temperatura
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