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1.
Food Chem ; 366: 130533, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274704

RESUMO

We performed a multiscale study to understand the impact of pure exogenous compounds at low concentration on the crystallization of triacylglycerols (TAGs) in anhydrous milk fat (AMF). We selected butyric acid, an inhibitor of crystallization, and palmitic acid, a promotor, to investigate the influence of the chain length. Tripalmitin was also used as a promotor to assess the impact of fatty acid esterification. Melted blends containing the additives (1 wt%) were quenched at 25 °C. X-ray scattering data showed that AMF TAGs crystallized directly in the ß'-2L form. The presence of additives did not modify the nanostructure of TAG crystals. However, they significantly altered the microstructure of AMF, as revealed by polarized light microscopy and rheology. This study emphasizes the interest of a multiscale approach to gain knowledge about the behavior of complex fat blends and of the use of modulators at low concentration to monitor their textural properties.


Assuntos
Ácidos Graxos não Esterificados , Nanoestruturas , Animais , Cristalização , Ésteres , Leite
2.
Food Chem ; 366: 130554, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284188

RESUMO

Standard fermentation (SF) mainly affected the metabolism of glycerophospholipid and sphingolipid, and increased the total lipid content of goat milk. Content of total lipid was decreased by magnetic fermentation compared with SF, mainly due to triacylglycerol and diacylglycerol. Comprehensive characteristic of lipids dynamic changes during standard and magnetic fermentation was performed using high-throughput quantitative lipidomics. Totally, 488 lipid molecular species covering 12 subclasses were detected, and triacylglycerol was the highest levels, followed by diacylglycerol and phosphoethanolamine in the whole fermentation stage. Specifically, except for ceramide and simple Glc series, the content of all polar lipids in SF was dropped and neutral lipids subjoined. Compared with SF, the decrease of triacylglycerol (1752.47 to 784.78 µg/mL), diacylglycerol (60.36 to 24.89 µg/mL) and simple Glc series (4.36 to 2.40 µg/mL) were observed, while ceramide (6.54 to 25.87 µg/mL) increased, suggesting magnetic fermentation as effective approach to potentially improve the nutritional of goat milk.


Assuntos
Lipídeos , Leite , Animais , Fermentação , Cabras , Lipídeos/análise , Fenômenos Magnéticos , Leite/química , Valor Nutritivo
3.
Food Chem ; 366: 130648, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325245

RESUMO

A novel label-free fluorescence aptasensor was established for chloramphenicol (CAP) detection by DNA four-arm junction-assisted target recycling and SYBR Green I dye-aided fluorescence-signal amplification. The CAP aptamer was hybridized to its complementary strand (primer) to form a double-stranded primer/aptamer complex. In the presence of CAP, aptamers can specifically bind with CAP to dissociate primers, which can trigger the self-assembly of four hairpins to continuously generate DNA four-arm junctions. After digesting the excess hairpins using T7 exonuclease, SYBR Green I was inserted into the base pair-rich DNA four-arm junctions, which led to a significant increase in fluorescence intensity. Under optimal conditions, the developed aptasensor can detect CAP in a linear range of 1.0 pg mL-1 to 10 ng mL-1 with a detection limit of 0.72 pg mL-1. The recovery rates in milk and honey ranged from 90.3% to 106.6%. Thus, the method shows substantial potential for CAP detection in food products.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Animais , Cloranfenicol/análise , DNA , Limite de Detecção , Leite/química
4.
Food Chem ; 367: 130700, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352694

RESUMO

Present study prepared curcumin-loaded nanoliposomes using bovine milk, krill phospholipids and cholesterol; and investigated the effects of cholesterol on membrane characteristics, storage stability and antibacterial properties of the curcumin nanoliposomes. Bovine milk phospholipids which have higher saturation than krill phospholipids resulted in formation of curcumin-loaded nanoliposomes with higher encapsulation efficiency (84.78%), larger absolute value of zeta potential and vesicle size (size: 159.15 ± 5.27 nm, zeta potential: -28.3 ± 0.62 mV). Cholesterol helps to formation of a more hydrophobic, compact and tighter bilayer membrane structure which improved the storage stability of nanoliposomes under alkaline (66.25 ± 0.46%), heat (43.25 ± 0.69%) and sunlight (49.44 ± 1.78%) conditions. In addition, curcumin-loaded nanoliposomes can effectively target infectious bacteria which secrete pore-forming toxins such as Staphylococcus aureus by causing the bacterial cell wall to lysis. Findings from present work can guide future development of novel antibacterial agents for use in food preservation.


Assuntos
Curcumina , Fosfolipídeos , Animais , Antibacterianos , Bovinos , Colesterol , Lipossomos , Leite , Tamanho da Partícula
5.
Food Chem ; 367: 130763, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34384984

RESUMO

Developing highly sensitive and visual methods for rapid detection of antibiotics is significant to ensure food quality and safety. To meet the requirement of nitrofuran antibiotics detection, luminescent fusiform Al(III)-containing metal-organic frameworks (Al-MOF) nanosheets were successfully synthesized by one-step hydrothermal method. And then, the nanosheet served as a fluorescent probe to detect nitrofuran via the inner-filter effect mechanism. The developed sensor allowed sensitive and selective detection of nitrofuran with good linear relationships. And, the detection limit (LOD) values were estimated to be 0.53, 0.838 and 0.583 µM for nitrofurazone, nitrofurantoin and furazolidone detection, respectively. The practical application of the proposed system was verified by HPLC in spiked milk samples with satisfying recoveries ranging from 88.14 to 126.21% and low relative standard deviations of 2.85 ~ 8.13%. Moreover, we designed fluorescent test papers for semi-quantitative detection of nitrofuran via naked-eye colorimetric assay. The established method provides an alternative strategy for semiquantitative detection of nitrofuran.


Assuntos
Estruturas Metalorgânicas , Nitrofuranos , Animais , Antibacterianos/análise , Corantes Fluorescentes , Leite/química , Nitrofuranos/análise
6.
Talanta ; 236: 122833, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635223

RESUMO

A dynamic pH junction was used in capillary electrophoresis (CE-DAD) to on-line preconcentrate, separate, and determine trace amounts of sulfonamide antibiotics (SAs) in milk and yoghurt samples in this study. A sample matrix with 0.15% acetic acid and 10% methanol (MeOH) at a pH of 4.0, and a background electrolyte (BGE) that contained 35 mM sodium citrate with 10% MeOH at a pH of 8.5, and an acidic barrage of 0.4% acetic acid with 10% MeOH at a pH of 2.5 were utilised to achieve a stacking effect for SAs through a dynamic pH junction. Under optimised conditions, the proposed preconcentration method showed good linearity (30-500 ng/mL, r2 ≥ 0.9940), low limits of detection (LODs) of 4.1-6.3 ng/mL, and acceptable analytes recovery (81.2-106.9%) with relative standard deviations (RSDs) within 5.3-13.7 (n = 9). The limits of quantification (LOQs) were below the maximum residue limit approved by the European Union (EU) in this type of matrices. Sensitivity enhancement factors of up to 129 were reached with the optimised dynamic pH junction using CE with a diode array detector (DAD). The method was used to determine SAs in fresh milk, low-fat milk, full-cream milk, and yoghurt samples.


Assuntos
Antibacterianos , Iogurte , Animais , Eletroforese Capilar , Concentração de Íons de Hidrogênio , Leite , Sulfonamidas
7.
Talanta ; 236: 122842, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635232

RESUMO

A fluorescent aptasensor based on sensitized terbium(III) luminescence was constructed to detect melamine in milk. Tb3+ as the fluorescence probe can be sensitized by a guanine-rich single-stranded DNA sequence, so the complementary sequence of the polythymidine aptamer (cDNA) was modified with six consecutive guanine bases (G6). In the absence of melamine, melamine aptamer combined with cDNA to form a double helix structure, and G6 hybridized with the extended cytosine bases in the aptamer, resulting in low fluorescence intensity of Tb3+. In the presence of melamine, cDNA was released due to the specific recognition of melamine to the aptamer, resulting in stronger sensitized fluorescence intensity of Tb3+. Under the optimum conditions, the linear concentration of melamine in the milk ranged from 1.0 µg/mL to 10.0 µg/mL. This aptasensor can be used for the accurate and rapid detection of melamine in milk with a detection limit of 0.02 µg/mL, and has the advantages of high sensitivity, high efficiency, simple operation and low cost.


Assuntos
Luminescência , Leite , Animais , Limite de Detecção , Leite/química , Triazinas/análise
8.
Trop Anim Health Prod ; 53(5): 489, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596781

RESUMO

The main aim of the current investigation was to evaluate the relationships between metabolic parameters, acute-phase proteins, and the outcome of treatment of Staphylococcus aureus subclinical mastitis in dairy cows. Serum metabolic parameters and milk haptoglobin were measured in two groups: S. aureus subclinical mastitis cows with successful treatment (n = 26) and S. aureus subclinical mastitis cows with unsuccessful treatment (n = 26). Significantly higher serum aspartate aminotransferase (AST), alkaline phosphatase (ALP), and LDL cholesterol concentrations were seen in subclinical mastitis cows with unsuccessful treatment compared to subclinical mastitis cows with successful treatment (p < 0.05). On the other hand, subclinical mastitis cows with successful treatment demonstrated higher serum iron and copper concentrations than the other group (p < 0.05). Comparison of measured variables before treatment revealed that cows suffering from subclinical mastitis with higher values of serum LDL cholesterol, ALP, and AST did not respond to antibiotic treatment and subclinical mastitis was persisted in the second examination, whereas subclinical mastitis cows with successful treatment demonstrated higher serum copper and iron concentrations (p < 0.05). The findings of the current investigation suggested that there was a relationship between the treatment outcome of S. aureus subclinical mastitis and trace element concentrations and liver health status. Furthermore, the present study provided cutoff values for serum LDL cholesterol, AST, ALP, iron, and copper, which would help predict the treatment outcome in cows with S. aureus subclinical mastitis.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Proteínas de Fase Aguda , Animais , Bovinos , Feminino , Mastite Bovina/tratamento farmacológico , Leite , Staphylococcus aureus , Resultado do Tratamento
9.
Trop Anim Health Prod ; 53(5): 495, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34601656

RESUMO

This study was conducted to evaluate the effect of time of feeding on production performance of West African Dwarf (WAD) goats. Two experiments involving twenty-seven goats (15 bucks and 12 gravid does) were conducted. In Experiment I, the bucks were randomly allocated into three treatments of five replicates and fed for 115 days. In experiment II, pregnant goat-does were randomly allocated into three experimental treatments of four replicates per treatment  1 month to kidding. Goats were either fed in the morning (06:00 h), afternoon (12:00 h), or evening (18:00 h) respectively under natural light cycles. In experiment I, dry matter intake, weight gain, carcass characteristic, and meat chemical composition were not affected (P > 0.05) by time of feeding. In experiment II, data collection on feed intake, feed efficiency (FE), and milk yield spanned 6 weeks and were analyzed. From the results, milk yield in morning-fed goat-does was higher than evening-fed does while afternoon-fed does have the lowest yield at P < 0.001. Energy corrected milk in evening-fed does was higher (P = 0.006) than other treatments. Feed efficiency for milk yield and energy corrected milk yield (P < 0.001) in evening-fed does were higher than morning and afternoon-fed does. Milk component yield (g/day) for lactose (P = 0.002) was the highest in morning-fed does; evening-fed does had the highest (P = 0.001) crude fat while afternoon-fed does had the lowest yield for all milk component parameters. Conclusively, feeding in the morning and evening is recommended for milk production and component yield per day. However, for improved energy corrected milk yield and feed efficiency in lactating goats, feeding in the evening is recommended. It is recommended that further studies should be conducted on improving milk productivity in evening-fed goats due to the advantage it had over other feeding regimes. Thus, altering time of feeding could be a suitable alternative feeding strategy in a changing climate with a potential to improve production efficiency, especially in the tropics.


Assuntos
Cabras , Lactação , Ração Animal , Animais , Dieta/veterinária , Ingestão de Alimentos , Feminino , Lactose , Leite , Gravidez
10.
Trop Anim Health Prod ; 53(5): 508, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34626253

RESUMO

Nanotechnology is the discipline and technology of small and specific things that are < 100 nm in size. Because of their extremely miniscule size, any changes in their chemical and physical structure may show higher reactivity and solubility than larger particles. Nanotechnology plays a vital role in every field of life. It is considered one of the most bleeding edge field of scientific research. It has already several applications in a myriad of disciplines while its application in the field of animal production and veterinary medicine is still experimental in nature. But, in recent years, the role of nanotechnology in the aforementioned fields of scientific inquiry has shown great progress. These days, nanotechnology has been employed to revolutionize drug delivery systems and diagnose atypical diseases. Applications of nanoparticle technology in the field of animal reproduction and development of efficacious vaccines have been at the forefront of scientific endeavors. Additionally, their impacts on meat and milk quality are also being judiciously inquired in recent decades. Veterinary nanotechnology has great potential to improve diagnosis and treatment, and provide new tools to this field. This review focuses on some noteworthy applications of nanoparticles in the field of animal production and their future perspectives.


Assuntos
Nanopartículas , Nanotecnologia , Animais , Sistemas de Liberação de Medicamentos/veterinária , Leite
11.
Trop Anim Health Prod ; 53(5): 504, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34622357

RESUMO

This study aimed to determine whether cows detected as tuberculosis (bTB) reactors and seropositive to brucellosis (bBR), as well as co-positive to bBR and bTB (bBR-bTB) and with a complete lactation before slaughter, were associated with reduced milk production and fertility. A total of 8068 productive and reproductive records of high-yielding Holstein cows from a single large dairy herd with a high prevalence of bTB and bBR were collected from 2012 to 2015. Lactation derived either from calving (n = 6019) or hormonally induced lactation (n = 2049), and all cows received growth hormone throughout lactation. For cows not induced into lactation, pregnancy rate to first service for healthy cows (C; 26.6%) was higher (P < 0.01) than bBR (15.2%), bTB (15.8%), and bBR-bTB (1.3%) cows. For induced cows, pregnancy rate to first service did not differ significantly among C, bBR, and bTB (14.5-17.3%) cows, but the percentage success of first service was extremely low (1.3%; P < 0.01) in bBR-bTB cows. Services per pregnancy (only pregnant cows) were lowest for C (3.3 ± 2.9; P < 0.01) and highest (6.4 ± 3.4) for bBR-bTB non-induced cows. This variable was lowest for C (2.9 ± 2.5; P < 0.01) and highest for bBR-bTB non-induced cows (6.3 ± 3.1). Pregnancy rate to all services did not differed for C (79.5%), bBR (76.7%), and bTB (75.9%) but was lower (58.9%; P < 0.01) for bBR-bTB non-induced cows. For induced cows this variable was highest for bBR (53.3%) and lowest for bBR-bTB (34.1%; P < 0.01) non-induced cows. 305-d milk production was increased by 4%, and total milk yield by 7% in TB-positive cows compared to that of the negative cows non-induced hormonally into lactation. This study showed the negative impact of the co-positivity for bTB and bBR on the reproductive efficiency of Holstein cows, although positive bTB and bBR tests enhanced milk yield.


Assuntos
Brucelose Bovina/diagnóstico , Doenças dos Bovinos , Fertilidade , Leite , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Feminino , Lactação , Gravidez
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(9): 1077-1082, 2021 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-34619924

RESUMO

Objective: To investigate sensitization rate of cow's milk in children, and explore its clinical features. Methods: This study enrolled a total of 818 patients under 18 years old with suspected food allergy who were admitted to the Allergy department in Beijing Shijitan Hospital during June 2018 to November 2020. The ImmunoCAP fluorescent enzyme-linked immunoassay system was used to quantify cow milk-specific immunoglobulin E (sIgE). Mild sensitization to cow's milk was defined as Radio-Allergo-Sorbent-Test (RAST) class 1, moderate sensitization was defined as class 2-3 and severe sensitization was class 4-6. Statistical methods such as χ2 test, independent sample t-test, one-way analysis of variance, and Spearman correlation analysis were used to retrospectively clarify differences of cow's milk sensitization rate between ages of children and elaborate its clinical features. Results: Overall sensitization rate of cow's milk reached 25.7% (210/818). Positive rate of cow milk sensitization (39.2%), cow milk sIgE levels [0.93 (0.52, 2.62)] kU/L, and moderate to severe sensitization rate (23.5%) were highest in infants aged between 0-3 years old. The sensitization rate and severity of sensitization declined with age. Most common clinical manifestation of cow milk sensitization was skin symptoms (50.0%), followed by respiratory symptoms (38.9%) and gastrointestinal symptoms (36.1%). Skin symptoms were the most common manifestation in 0-3 year-old group (47.3%), and respiratory symptoms were more common in 4-6 and 7-18 year-old groups (58.7%, 56.0%). Multiple-sensitization rate of patients with moderate to severe cow milk sensitization was 74.1%, most of which (70.4%) were co-sensitized by other food allergens, and 31.5% were co-sensitized by inhaled allergens. Conclusions: In population with age under 18 years old, infants aged between 0-3 years old suffered highest cow milk sensitization rate and increased sensitization severity. Then the severity decreased with age increasing. Patients with cow milk sensitization manifested skin symptoms most.


Assuntos
Hipersensibilidade a Leite , Leite , Adolescente , Alérgenos , Animais , Bovinos , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E , Lactente , Recém-Nascido , Estudos Retrospectivos
13.
Sensors (Basel) ; 21(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34640926

RESUMO

Sulfamethazine (SMZ) as a broad antibiotic is widely used in livestock and poultry. However, the abuse of SMZ in livestock feed can lead to SMZ residues in food and the resistance of bacteria to drugs. Thus, a method for the detection of SMZ in food is urgently needed. In this study, quantum dot (QD) nanobeads (QBs) were synthesized by encapsulating CdSe/ZnS QDs using a microemulsion technique. The prepared QBs as signal probes were applied in lateral flow immunoassay (LFIA) for the detection of SMZ in chicken and milk. Our proposed method had limits of detection of 0.1138-0.0955 ng/mL and corresponding linear ranges of 0.2-12.5, 0.1-15 ng/mL in chicken and milk samples, respectively. The recovery of LFIA for the detection of SMZ was 80.9-109.4% and 84-101.6% in chicken and milk samples, respectively. Overall, the developed QBs-LFIA had high reliability and excellent potential for rapid and sensitive screening of SMZ in food.


Assuntos
Pontos Quânticos , Animais , Galinhas , Imunoensaio , Leite/química , Reprodutibilidade dos Testes , Sulfametazina/análise
14.
Braz J Biol ; 82: e254111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495171

RESUMO

This article presents the results of the level of feeding and the health status of dairy cows in a commercial dairy farm on the content of the main components in milk (fat, protein, urea). The aim of the research was to study the milk productivity and composition of milk of cows, to analyze the level of feeding and the content of basic nutrients in the diet of the farm. The farm breeds purebred Holstein cattle with a high genetic potential for productivity. The milking herd was formed in 2009 on the basis of 600 heads of Holstein-Friesian heifers imported from Hungary, as well as 65 heads of Holsteinized heifers of Ukrainian selection from Ukraine in 2015. Today the livestock numbers about 1,500 head of cattle, of which there are about 900 breeders. On the territory of the farm there are: 3 cowsheds for keeping cows, an insemination room, a milking parlor with a parallel installation of the Delaval company, in which 48 cows are milked for one milking, the ABK, where the manager's office, livestock technician, accounting is located, and a mini-hotel with dining room and lounges. Dairy bases are equipped with auto-drinkers, ventilation, plumbing, electric lighting, manure removal mechanisms, and a milking installation. The object of the research was Holstein cows in the amount of 483 heads of Aina Dairy Farm LLP. The studies were carried out according to generally accepted zootechnical methods using modern equipment for conducting analyzes and interstate and state standards. The research results showed that the milk productivity of cows averaged 19.5 kg per day, the fat content 4.3%, the protein 3.9%, the number of somatic cells 230.5 thousand units / ml, urea 45.3 mg / 100 ml respectively. Analyzing the level of urea in milk can suggest a high crude protein content in the diet. The ration of feeding dairy cows on the farm is concentrate-silage-haylage and there is an excess of dry matter by 16.2%, crude protein by 9.8%, starch by 29.4%, respectively.


Assuntos
Lactação , Leite , Animais , Bovinos , Dieta , Fazendas , Feminino
15.
Talanta ; 235: 122779, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517637

RESUMO

To ensure the safety of dairy products, especially milk, and consequently protect human health, accurate and simple analytical techniques are highly necessary to determine the low concentration of aflatoxin M1 (AFM1) as an important carcinogen. Herein, a novel, accurate and simple fluorescent aptasensor was designed for selective detection of AFM1 based on bivalent binding aptamer-cDNA (BBA-cDNA) structure. Moreover, MoS2 nanosheets (MoS2 NSs) were used as the fluorescent quencher and FAM-labeled complementary strand of aptamer (FAM-CS) was applied as a fluorescent probe. In this study, we achieved a new result. Unlike previous studies, in this work, the BBA-cDNA structure was not disassembled in the presence of the target. Therefore, as the AFM1 concentration increased, more targets were attached to the BBA-cDNA structure and as a result, the BBA-cDNA structure/AFM1 could not be placed on the surface of MoS2 NSs, leading to the more fluorescent intensity detection. Under optimized conditions, the developed fluorescent analytical method revealed great selectivity toward AFM1 with a limit of detection (LOD) of 0.5 nM and a linear range from 0.7 to 10 nM. This fabricated aptasensor indicated excellent analytical performance for AFM1 detection in milk samples with LOD of 0.1 nM. Overall, the proposed approach could provide an effective basis for small molecule analysis to guarantee food and human safety using appropriate aptamer sequences.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aflatoxina M1/análise , Animais , DNA Complementar , Humanos , Limite de Detecção , Leite/química , Molibdênio
16.
Anal Chim Acta ; 1178: 338802, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482881

RESUMO

Dispersive micro solid-phase extraction procedure using a novel and selective sorbent prepared from four components was developed as a sample preparation strategy for extracting five organophosphorus pesticides, including fenitrothion, malathion, ethion, and chlorpyrifos, and diazinon in several vegetables, fruit juices, and cow's milk samples. Due to the high importance of the sorbent in the microextraction process, the percentages of sorbent components, including metal-organic framework (ZIF-67), chitosan, magnetic Fe3O4 nanoparticles, and silica nanoparticles, were optimized by a simplex lattice mixture design. After optimizing the sorbent composite, effective parameters on the extraction of organophosphorus pesticides were optimized using a definitive screening design and Box-Behnken design, respectively. A surfactant (Triton X100) as a dispersion agent with a low volume (10 µL) was utilized in the microextraction procedure to reduce the sorbent dispersion time and increase the sorbent dispersion efficiency. Under the optimal conditions, linearity for the determination of fenitrothion, malathion, ethion, chlorpyrifos, and diazinon was in the concentration ranges of 0.13-1100, 0.27-1000, 0.38-1000, 0.21-1200, and 0.11-1100 ng mL-1 with a determination coefficient higher than 0.9906, respectively. The quantitation limits, detection limits, and relative standard deviations (n = 5) were lower than 0.38 ng mL-1, 0.11 ng mL-1, and 4.59% for the determination of organophosphorus pesticides. The method application for measuring OPPs on cucumber, carrot, tomato, apple juice, orange juice, and cow's milk indicated the presence of residual amounts of malathion in a cucumber sample, diazinon in a carrot sample, and chlorpyrifos in a tomato sample.


Assuntos
Resíduos de Praguicidas , Praguicidas , Animais , Sucos de Frutas e Vegetais , Limite de Detecção , Fenômenos Magnéticos , Leite/química , Compostos Organofosforados/análise , Praguicidas/análise , Extração em Fase Sólida , Verduras , Água/análise
17.
Trop Anim Health Prod ; 53(5): 463, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34545452

RESUMO

Lactation curves are a valuable tool for improving flock production efficiency, adjusting flock sizes, and improving farmers' income in grazing-based livestock production. Therefore, we used natural cubic splines to estimate (a) a general flock production pattern throughout a year, (b) an average lactation curve, and (c) patterns of milk chemical components in dual-purpose goats grazing in arid plant communities in the Sierra de San Francisco, Baja California Peninsula, during years of abundant precipitation. Also, milk chemical composition was compared between flocks. Annual flock milk production showed a wiggly pattern with two greater waves in summer and spring. The average individual lactation curve (kg/doe/day) and production curves of fat, protein, lactose, and ashes (g/doe/day) showed a decreasing and wiggly pattern across 35-week lactation; the greatest average daily production was in week 2. Milk, protein, lactose, and ash production curves had similar persistency values that were greater than those of the fat production curve. Milk production had a high-positive correlation with fat production and very high-positive correlations with protein, lactose, and ash production. Density (g/ml) and fat, protein, lactose, and ash contents (%) showed a ditch-shaped pattern across lactation, with greater values at the end. Goat flocks grazing across plant communities produced different quality milk. Thus, native plant communities are a valuable resource that favors a great fat content and moderate protein content in local goat milk. Also, breeding programs must pay attention that an increment in individual milk production could decrease fat and protein production, which are valuable for cheesemaking.


Assuntos
Cabras , Leite , Animais , Feminino , Lactação , Lactose , México , Proteínas do Leite
18.
Trop Anim Health Prod ; 53(5): 464, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34545480

RESUMO

The milk productivity improvement of she-camels requires a good feeding program that should indicate appropriate foods, required quantities, and how and when to distribute them. The aim of this study was to explore the interactions between milk productivity and body variations of dairy camels in response to experimental dietary treatments. The camels received a new diet every 15 days approximately, with higher rate of concentrates and high energy concentration. Results showed that diets with high energy or protein density, UFL (forage unit for milk production), and nutrient waste stimulated the development of body weight at the expense of milk production (p <0.05). Therewith, the inadequate supply of feeds rich in fermentable carbohydrates such as dates (p <0.01) or corn (p <0.05) compromised milk productivity level in favor of ADG (average daily gain) and body reserves deposit. Increasing the level of roughage feed intake had a positive effect on milk production (p < 0.05). According to the results, it is recommended in the feeding of dairy she-camels to maintain a minimum level of roughage at more than 60%. In addition, it is necessary that the energy density (DER) be in the order of 0.91-1.17 maximum (0.78 UFL/kg.DM-dry matter). Taking into account famous nitrogen recycling mechanisms of camels, the protein supply of diets does not seem useful to overcome 63 g PDI/kg.DM (PDI protein digestible in the intestine).


Assuntos
Camelus , Rúmen , Ração Animal/análise , Animais , Dieta/veterinária , Digestão , Fermentação , Lactação , Leite , Rúmen/metabolismo , Zea mays
19.
Trop Anim Health Prod ; 53(5): 447, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34532774

RESUMO

The floor surface of the cubicle is a detrimental factor on cow comfort. The effects of two floor types, rubber and concrete, on dairy cow comfort and milk production were compared for a period of 13 weeks. Fourteen Friesian crossbred dairy cows with an average body weight of 425.67 ± 61.12 kg (mean ± SD), nose to tail body length of 2.07 ± 0.15 m, rump height of 1.29 ± 0.02 m, hook bone width of 0.48 ± 0.05 m, and body condition score (BCS) of 4.13 ± 0.44 were used, with seven cows per flooring treatment. The cows produced a mean of 15.93 ± 4.03 l/cow/day and a constant feeding plan was practiced. The swelling and wound severity of hocks diminished (P < 0.05) starting at the third and tenth weeks, respectively. Daily lying time/h (concrete: 9.67 ± 1.24, rubber: 10.60 ± 0.69, P = 0.046) and average duration of lying bouts/min increased (concrete: 58.16 ± 7.74, rubber: 65.66 ± 9.85, P = 0.050) starting from the twelfth week on rubber bedding. Prevalence of mastitis, lameness, and cow cleanliness remained unchanged on floor treatments. A progressive increase in daily milk production/l (concrete: 13.37 ± 1.46, rubber: 16.67 ± 2.24, P = 0.007) of cows in rubber bedding was observed at the fourth week of the experiment. Hence, the current study suggests that the use of softer bedding such as rubber mats could improve cow comfort and daily milk production of cows.


Assuntos
Doenças dos Bovinos , Tarso Animal , Animais , Comportamento Animal , Bovinos , Doenças dos Bovinos/epidemiologia , Indústria de Laticínios , Feminino , Pisos e Cobertura de Pisos , Abrigo para Animais , Coxeadura Animal , Leite , Borracha , Sri Lanka
20.
J Anim Sci ; 99(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468760

RESUMO

The main objective of this study was to evaluate the effect of peripartal administration of a commercially available nonspecific immune stimulant (mycobacterium cell wall fraction; MCWF [Amplimune, NovaVive Inc., Napanee, ON, Canada]) on the incidence of disease during early lactation and subsequent fertility of dairy cows. A second objective was to characterize the dynamics of circulating white blood cells (WBC) and metabolic markers following treatment administration. Cows in an United States Department of Agriculture (USDA) organic-certified dairy herd were blocked by parity and, based on sequential calving dates, randomly assigned to receive two injections (5 mL s.c.) of either a placebo (saline solution) as a control (CON; n = 71) or MCWF (n = 65) at enrollment (7 d before expected calving) and within 24 h after calving. Blood samples were collected from a subsample of the study population (MCWF = 16; CON = 18) for WBC count at enrollment, at day 2 post enrollment, and at days 1, 3, 7, and 14 after calving. Serum fatty acids, beta-hydroxybutyrate, and Ca concentrations were determined at days 1 and 7 postpartum (MCWF = 21; CON = 21). Main outcome variables included incidence risk of peripartal and early lactation health disorders and pregnancy at first artificial insemination (AI), at 100, and at 150 days in milk (DIM). In addition, the average daily milk yield up to 90 DIM and death and live culling before 305 DIM were compared. Treatment effects were assessed using multivariable logistic regression, time-to-event analyses, and repeated measures analysis of variance (ANOVA). A treatment effect on the incidence risk of some of the health disorders in the study was established. Incidence risk of metritis and clinical mastitis <28 DIM was smaller in MCWF than in CON cows (36.9% vs. 50.7% and 6.3% vs. 19.7%, respectively). On the contrary, the incidence risk of respiratory disease <28 DIM was smaller in CON (0%) than in MCWF (7.7%). Reproductive performance of multiparous cows was affected by MCWF administration: pregnancy at first AI and pregnancy at 100 and 150 DIM were greater in MCWF than in CON (35.6% vs. 19.2%; 51.1% vs. 25.0%; and 64.4% vs. 40.4%, respectively). Overall, median intervals from calving to pregnancy were 90 vs. 121 d in MCWF and CON cows, respectively. No treatment effects on the dynamics of circulating WBC or in postpartum metabolic status were established. No differences for milk yield or for the proportion of cows that survived up to 305 DIM were determined, although cows in MCWF left the herd earlier than cows in CON. In conclusion, incidence risks of metritis and mastitis in early lactation were smaller in cows receiving MCWF, whereas the incidence risk of respiratory disease was smaller in CON. Fertility significantly improved in MCWF compared with CON cows. As this study was performed in an organic-certified dairy, specific health and reproductive management practices may affect the external validity of the current findings.


Assuntos
Doenças dos Bovinos , Mycobacterium , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Parede Celular , Feminino , Fertilidade , Lactação , Leite , Período Pós-Parto , Gravidez , Reprodução
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