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1.
PLoS One ; 15(8): e0231125, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866172

RESUMO

Korean peninsula weather is rapidly becoming subtropical due to global warming. In summer 2018, South Korea experienced the highest temperatures since the meteorological observations recorded in 1907. Heat stress has a negative effect on Holstein cows, the most popular breed of dairy cattle in South Korea, which is susceptible to heat. To examine physiological changes in dairy cows under heat stress conditions, we analyzed the profiles circulating microRNAs isolated from whole blood samples collected under heat stress and non-heat stress conditions using small RNA sequencing. We compared the expression profiles in lactating cows under heat stress and non-heat stress conditions to understand the regulation of biological processes in heat-stressed cows. Moreover, we measured several heat stress indicators, such as rectal temperature, milk yield, and average daily gain. All these assessments showed that pregnant cows were more susceptible to heat stress than non-pregnant cows. In addition, we found the differential expression of 11 miRNAs (bta-miR-19a, bta-miR-19b, bta-miR-30a-5p, and several from the bta-miR-2284 family) in both pregnant and non-pregnant cows under heat stress conditions. In target gene prediction and gene set enrichment analysis, these miRNAs were found to be associated with the cytoskeleton, cell junction, vasculogenesis, cell proliferation, ATP synthesis, oxidative stress, and immune responses involved in heat response. These miRNAs can be used as potential biomarkers for heat stress.


Assuntos
MicroRNA Circulante/genética , Resposta ao Choque Térmico/genética , Lactação/genética , Animais , Cruzamento , Bovinos , Doenças dos Bovinos/genética , Feminino , Perfilação da Expressão Gênica/métodos , Transtornos de Estresse por Calor/sangue , Temperatura Alta , MicroRNAs/genética , Leite/metabolismo , Gravidez , RNA Circular/genética , República da Coreia , Estações do Ano , Análise de Sequência de RNA/métodos
2.
Anim Sci J ; 91(1): e13454, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32959464

RESUMO

This study investigated the effects of substituting ear corn silage (ECS) for commercial formula feed on milk production and milk fatty acid profiles in grazing dairy farms during the summer season. A field survey was conducted on five grazing dairy farms in every summer month of 2017, 2018, and 2019. Three of the five farms substituted fresh ECS for the commercial formula feed at a ratio of 2:1 from July of each year (ECS farms). Other farms maintained the same feeding management as before (non-ECS farms). An interview survey was conducted on each farm to calculate feed intake and milk yield per cow. Feed and milk samples were collected in each survey. Milk compositions and milk fatty acid profiles were determined. The substitution of ECS for the commercial formula feed did not affect milk yield or milk composition, but ECS farms maintained low levels of milk urea compared with non-ECS farms (p < .01). The ECS substitution also influenced some of the milk fatty acid proportions; C16:0 and C16:1 increased, and trans-11 C18:1, cis-9,trans-11 C18:2, and the sum of polyunsaturated fatty acids decreased, while these fatty acid proportions were maintained in non-ECS farms throughout the summer season (p < .05).


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Bovinos/metabolismo , Bovinos/fisiologia , Indústria de Laticínios , Dieta/veterinária , Suplementos Nutricionais , Ácidos Graxos/análise , Herbivoria/fisiologia , Lactação/fisiologia , Leite/metabolismo , Silagem , Zea mays , Animais , Feminino
3.
Chemosphere ; 258: 127387, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947680

RESUMO

It is well known that serum is an ideal and potential choice to reflect the toxicity of fluoride. However, the effects of fluoride on serum metabolome have not been reported until now. In this study, the models of 3-week-old rats exposed fluoride by breast milk and 11-week-old rats exposed fluoride via breast milk and drinking water containing sodium fluoride (100 mg/L) were established. Using Ultra Performance Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (UPLC-MS/MS), as compared with control group, 28 negative (NEG) and 52 positive (POS) metabolites were significantly up-regulated, meanwhile 30 NEG and 21 POS significantly down-regulated metabolites were found in serum of 3-week-old rats exposed to fluoride. For 11-week-old fluorosis rats, there were 119 NEG and 65 POS metabolites significantly increased, and 7 NEG, 5 POS metabolites were obviously decreased. Importantly, nicotinamide, adenosine, 1-Oleoyl-sn-glycero-3-phosphocholine (OGPC), and 1-Stearoyl-sn-glycerol 3-phosphocholine (SGPC) were shared by two models. The metabolites of urea cycle, such as urea and N2-Acetyl-l-ornithine, betaine as a methyl donor, were regarded to reflect the fluorosis degree. These metabolites could be the potential markers of fluorosis, contributing to the prevention and treatment of fluorosis.


Assuntos
Fluoretos/toxicidade , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Betaína , Cromatografia Líquida , Água Potável/química , Feminino , Humanos , Masculino , Metabolômica , Leite/metabolismo , Ratos , Fluoreto de Sódio , Espectrometria de Massas em Tandem
4.
Food Chem ; 332: 127384, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615384

RESUMO

Dairy polar lipids (PL) seem to exhibit antiplatelet effects. However, it is not known what molecular species may be responsible. In this study, we confirmed using C30 reversed-phase (C30RP) ultra-high-performance liquid chromatography (UHPLC) coupled to high resolution accurate mass tandem mass spectrometry (HRAM-MS/MS) that fermentation of yoghurts from ovine milk using specific starter cultures altered the PL composition. These lipid alterations occurred concomitant with increased antithrombotic properties of the yoghurts PL fractions against platelet-activating factor (PAF) and thrombin-induced platelet aggregation. Specifically, elevation in phosphatidylethanolamine (PE), sphingomyelin (SM), phosphatidylcholine (PC) and their molecular species were observed following yoghurt fermentation. Furthermore, PC(18:0/18:1), PE(18:1/18:2), SM(d18:0/22:0) and several other molecular species were significantly inversely correlated with the inhibition of PAF and thrombin. These molecular species were abundant in the most bioactive yoghurts fermented by S. thermophilus and L. acidophilus, which suggest that fermentation by these microorganisms increases the antithrombotic properties of ovine milk PL.


Assuntos
Lipídeos/análise , Leite/metabolismo , Inibidores da Agregação de Plaquetas/análise , Iogurte/análise , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cromatografia Líquida de Alta Pressão , Fermentação , Lipídeos/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/farmacologia , Ovinos , Esfingomielinas/metabolismo , Espectrometria de Massas em Tandem , Trombina/farmacologia
5.
PLoS One ; 15(7): e0234610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645008

RESUMO

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


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Dieta/veterinária , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso Corporal , Bovinos , Fibras na Dieta/metabolismo , Masculino , Leite/metabolismo , Nutrientes , Rúmen/metabolismo , Desmame , Ganho de Peso , Zea mays/metabolismo
6.
Food Chem ; 332: 127413, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32652410

RESUMO

Mass spectrometry-based methods coupled with stable isotope dilution have become effective and widely used methods for the detection and quantification of food allergens. Current methods target signature peptides resulting from proteolytic digestion of proteins of the allergenic ingredient. The choice of appropriate stable isotope-labelled internal standard is crucial, given the diversity of encountered food matrices which can affect sample preparation and analysis. We propose the use of concatemer, an artificial and stable isotope-labelled protein composed of several concatenated signature peptides as internal standard. With a comparative analysis of three matrices contaminated with four allergens (egg, milk, peanut, and hazelnut), the concatemer approach was found to offer advantages associated with the use of labelled proteins, ideal but unaffordable, and circumvent certain limitations of traditionally used synthetic peptides as internal standards. Although used in the proteomic field for more than a decade, concatemer strategy has not yet been applied for food analysis.


Assuntos
Alérgenos/análise , Proteômica/métodos , Alérgenos/metabolismo , Sequência de Aminoácidos , Animais , Arachis/metabolismo , Cromatografia Líquida de Alta Pressão , Corylus/metabolismo , Ovos/análise , Marcação por Isótopo , Espectrometria de Massas , Leite/metabolismo , Isótopos de Nitrogênio/química , Peptídeos/análise , Peptídeos/química , Proteômica/normas , Padrões de Referência , Espectrometria de Massas em Tandem
7.
Gene ; 759: 144981, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32707300

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARG), as a member of the nuclear receptor superfamily, plays an important role in adipocyte differentiation and regulation of lipid and glucose metabolism. In this study, the transcripts of PPARG gene were isolated and identified in buffalo mammary gland. The results showed that two types of transcripts (PPARG1 and PPARG2) of PPARG gene produced by alternative 5' end use were expressed in buffalo mammary gland, and each of them had four different alternative splicing variants. The PPARG1 includes PPARG1a, PPARG1b, PPARG1c and PPARG1d, while the PPARG2 contains PPARG2a, PPARG2b, PPARG2c and PPARG2d. Among them, only PPARG1a, PPARG2a and PPARG2d can encode complete functional proteins with three complete functional domains, and the rest encode truncated proteins with incomplete functional domains. All the eight variants of PPARG protein do not contain transmembrane regions and signal peptides, but their conserved domain, secondary and tertiary structure and subcellular localization were different. Subcellular localization confirmed that the main transcripts PPARG1a and PPARG2a played a functional role in the nucleus, which was consistent with the results by in silico prediction. RT-qPCR analysis of buffalo mammary tissue showed that the mRNA expression levels of PPARG1 and PPARG2 in lactation were higher than those in non-lactation, and the expression levels of transcripts PPARG2d and PPARG1b + PPARG2b in lactating stage were also higher than those in non-lactating stage, but the mRNA abundance of transcripts PPARG1c, PPARG1d and PPARG2c in non-lactating period was higher than that in lactating period. The results of this study suggest that PPARG1 and PPARG2 may play important role in buffalo milk fat synthesis, and the eight alternative splicing variants found here are likely to be related to the post-transcriptional regulation of lactation.


Assuntos
Búfalos/genética , Glândulas Mamárias Animais/metabolismo , PPAR gama/genética , Animais , Feminino , Lactação/genética , Leite/metabolismo , PPAR gama/metabolismo
8.
Anticancer Res ; 40(8): 4701-4706, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727795

RESUMO

BACKGROUND/AIM: Bovine mastitis is caused by the invasion and propagation of pathogenic microorganisms into the udder and mammary gland tissues of cattle. In this study, the therapeutic effect of a low-molecular-weight whey protein (LMW-WP) on bovine mastitis was evaluated. MATERIALS AND METHODS: LMW-WP was orally, intraperitoneally, and vaginally administered to bovine with mastitis. The number of somatic cells in milk was measured 24 h before the administration of LMW-WP. The effect of LMW-WP on cytokine production was measured with a microarray that evaluates the expression of cytokines. RESULTS: In the group that received 1,000 mg intraperitoneally, the somatic cell count was reduced to less than 400,000 at the shipment standard value in three of the four udders, indicating 75% efficacy. The group that received 1,000 mg by vaginal administration showed 67% efficacy. It was confirmed that LMW-WP increased the production of cytokines such as IL-5, IL-6, IL-9, IL-12, MCP-1, and VEGF in mouse macrophage cells, but it did not show any antibacterial activity. CONCLUSION: LMW-WP may be an effective therapeutic agent for bovine mastitis.


Assuntos
Macrófagos/efeitos dos fármacos , Mastite Bovina/tratamento farmacológico , Proteínas do Soro do Leite/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Contagem de Células/métodos , Linhagem Celular , Citocinas/metabolismo , Feminino , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/microbiologia , Camundongos , Leite/metabolismo , Células RAW 264.7
9.
Anim Sci J ; 91(1): e13389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32515521

RESUMO

Efforts to improve dairy performance have been focused on increasing milk productivity of cows through improved feeding systems and genetic potential. However, methods for evaluating milking system performance based on milk productivity have not yet been established. Milking system performance was evaluated by measuring the claw vacuum at five flow rates (1.9-8.7 kg/min) produced using a flow simulator for a single eight-swing milking parlor with a high-line system. Based on these results, a double eight-parallel milking parlor with a low-line system was installed and tested. Farmers can take data obtained from evaluations of milking system performance into account for future management decisions, such as renewing the milking system. By renewing the milking system, average milking productivity, somatic cell linear score (LS) of bulk milk, and LS of each cow were significantly improved in the year after installing the new system (p < .01). In addition to checking conventional milking systems, this novel diagnostic method using a flow simulator can be used for checking new installations and also for proposing renovations.


Assuntos
Bovinos/metabolismo , Bovinos/fisiologia , Indústria de Laticínios/instrumentação , Lactação/fisiologia , Leite/metabolismo , Animais , Indústria de Laticínios/métodos , Feminino , Qualidade dos Alimentos
10.
Food Chem ; 330: 127324, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569938

RESUMO

Enzymes currently used in cheesemaking have various drawbacks, and there is a continual need to find new coagulants. This study describes the extraction and biochemical characterization of two proteases from the red alga Gracilaria edulis. The proteases were extracted with phosphate buffer and partially purified by ammonium sulphate precipitation and dialysis. The enzymes exhibited optimum caseinolytic activity at 60 °C and a pH range of 6-8. They showed a high ratio of milk-clotting over caseinolytic activity, indicating they had an excellent milk-clotting ability. The proteases were confirmed to be serine protease and metalloprotease with molecular weight (MW) of 44 and 108 kDa. They exhibited high hydrolytic activity on κ-caseins, cleaving κ-casein at four main sites, one of which being the same as that of calf rennet, which is the first reported for an algal protease. The findings demonstrated that the proteases could potentially be used as a milk coagulant in cheesemaking.


Assuntos
Caseínas/metabolismo , Gracilaria/enzimologia , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Alga Marinha/enzimologia , Sulfato de Amônio , Animais , Caseínas/química , Fracionamento Químico , Quimosina/metabolismo , Eletroforese em Gel de Poliacrilamida , Gracilaria/química , Concentração de Íons de Hidrogênio , Hidrólise , Leite/química , Leite/metabolismo , Peso Molecular , Peptídeo Hidrolases/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Alga Marinha/química , Serina Proteases/química , Serina Proteases/isolamento & purificação , Serina Proteases/metabolismo , Espectrometria de Massas em Tandem , Temperatura
11.
BMC Evol Biol ; 20(1): 70, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560628

RESUMO

BACKGROUND: Lipids contained in milk are an essential source of energy and structural materials for a growing neonate. Furthermore, lipids' long-chain unsaturated fatty acid residues can directly participate in neonatal tissue formation. Here, we used untargeted mass spectrometric measurements to assess milk lipid composition in seven mammalian species: humans, two macaque species, cows, goats, yaks, and pigs. RESULTS: Analysis of the main milk lipid class, triacylglycerides (TAGs), revealed species-specific quantitative differences in the composition of fatty acid residues for each of seven species. Overall, differences in milk lipid composition reflect evolutionary distances among species, with each species group demonstrating specific lipidome features. Among them, human milk contained more medium and long-chain unsaturated fatty acids compared to other species, while pig milk was the most distinct, featuring the highest proportion of long-chain polyunsaturated fatty acids. CONCLUSIONS: We show that milk lipidome composition is dynamic across mammalian species, changed extensively in pigs, and contains features particular to humans.


Assuntos
Lipidômica , Leite/metabolismo , Animais , Bovinos , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Haplorrinos , Humanos , Lactação , Especificidade da Espécie , Suínos
12.
J Dairy Sci ; 103(7): 6576-6582, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32448581

RESUMO

The objectives of this study were (1) to evaluate if hyperketonemia in dairy cows (defined as plasma ß-hydroxybutyrate ≥1.0 mmol/L) can be predicted using on-farm cow data either in current or previous lactation week, and (2) to study if adding individual net energy intake (NEI) can improve the predictive ability of the model. Plasma ß-hydroxybutyrate concentration, on-farm cow data (milk yield, percentage of fat, protein and lactose, fat- and protein-corrected milk yield, body weight, body weight change, dry period length, parity, and somatic cell count), and NEI of 424 individual cows were available weekly through lactation wk 1 to 5 postpartum. To predict hyperketonemia in dairy cows, models were first trained by partial least square discriminant analysis, using on-farm cow data in the same or previous lactation week. Second, NEI was included in models to evaluate the improvement of the predictability of the models. Through leave-one trial-out cross-validation, models were evaluated by accuracy (the ratio of the sum of true positive and true negative), sensitivity (68.2% to 84.9%), specificity (61.5% to 98.7%), positive predictive value (57.7% to 98.7%), and negative predictive value (66.2% to 86.1%) to predict hyperketonemia of dairy cows. Through lactation wk 1 to 5, the accuracy to predict hyperketonemia using data in the same week was 64.4% to 85.5% (on-farm cow data only), 66.1% to 87.0% (model including NEI), and using data in the previous week was 58.5% to 82.0% (on-farm cow data only), 59.7% to 85.1% (model including NEI). An improvement of the accuracy of the model due to including NEI ranged among lactation weeks from 1.0% to 4.4% when using data in the same lactation week and 0.2% to 6.6% when using data in the previous lactation week. In conclusion, trained models via partial least square discriminant analysis have potential to predict hyperketonemia in dairy cows not only using data in the current lactation week, but also using data in the previous lactation week. Net energy intake can improve the accuracy of the model, but only to a limited extent. Besides NEI, body weight, body weight change, milk fat, and protein content were important variables to predict hyperketonemia, but their rank of importance differed across lactation weeks.


Assuntos
Doenças dos Bovinos/sangue , Ingestão de Energia , Cetose/veterinária , Leite/metabolismo , Ácido 3-Hidroxibutírico/sangue , Animais , Peso Corporal , Bovinos , Análise Discriminante , Fazendas , Feminino , Cetose/sangue , Lactação , Lactose/metabolismo , Análise dos Mínimos Quadrados , Leite/química , Proteínas do Leite/metabolismo , Paridade , Período Pós-Parto , Gravidez , Sensibilidade e Especificidade
13.
Am J Clin Nutr ; 112(2): 427-446, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32469393

RESUMO

BACKGROUND: Multinutrient protein-enriched supplements are promoted to augment the effects of exercise on muscle mass and strength, but their effectiveness in middle-aged women, or whether there are any additional benefits to physical function, remains uncertain. OBJECTIVES: We aimed to evaluate whether a multinutrient-fortified milk drink (MFMD) could enhance the effects of exercise on functional muscle power (stair climbing) in middle-aged women. Secondary aims were to evaluate the intervention effects on physical function, muscle strength, lean mass (LM), fat mass (FM), bone mineral content (BMC), muscle cross-sectional area (CSA), muscle density, balance, flexibility, aerobic fitness, inflammation, oxidative stress, bone and cartilage turnover, blood pressure, and blood lipids. METHODS: In this 4-mo, double-blind, placebo-controlled, randomized trial, 244 women (45-65 y) participated in a multimodal resistance-type exercise program 3 d/wk, with random allocation to a twice-daily MFMD containing added protein, vitamin D, calcium, milk fat globule membrane (phospholipids and other bioactives), and other micronutrients (Ex + MFMD, n = 123) or an energy-matched placebo (Ex + placebo, n = 121). RESULTS: A total of 216 women (89%) completed the study. After 4 mo, both groups experienced similar 3.6%-4.3% improvements in the primary outcomes of fast-pace 5- and 10-step stair ascent power. In contrast, Ex + MFMD experienced greater improvements in 5-step regular-pace stair descent time [net difference (95% CI): -0.09 s (-0.18, 0.00 s), P = 0.045], countermovement jump height [0.5 cm (0.04, 1.0 cm), P = 0.038], total body LM [0.3 kg (0.04, 0.60 kg), P = 0.020], FM [-0.6 kg (-1.0, -0.2 kg), P = 0.004], BMC [0.4% (0.1%, 0.6%), P = 0.020], muscle CSA [thigh: 1.8% (0.6%, 2.9%), P = 0.003; lower leg: 0.9% (0.3%, 1.6%), P = 0.005], balance eyes closed [3.3 s (1.1, 5.4 s), P = 0.005], 2-min step performance [8 steps (3, 12 steps), P = 0.003], and sit-and-reach flexibility [1.4 cm (0.6, 2.2 cm), P = 0.026]. MFMD did not enhance the effects of exercise on any measures of muscle strength, gait speed, dynamic balance, reaction time, or blood lipids, and there was no effect of either intervention on blood pressure, markers of inflammation, or cartilage turnover. Ex + placebo had a greater improvement in the oxidative stress marker protein carbonyls (P < 0.01). CONCLUSIONS: In middle-aged women, daily consumption of an MFMD did not enhance the effects of a multimodal exercise program on the primary outcome of stair climbing ascent power, but did elicit greater improvements in multiple secondary outcomes including various other measures of functional performance, LM, muscle size, FM, balance, aerobic capacity, flexibility, and bone metabolism.This trial was registered at www.anzctr.org.au as ACTRN12617000383369.


Assuntos
Envelhecimento/metabolismo , Leite/metabolismo , Músculo Esquelético/fisiologia , Estresse Oxidativo , Vitaminas/metabolismo , Idoso , Envelhecimento/imunologia , Animais , Composição Corporal , Densidade Óssea , Osso e Ossos/química , Osso e Ossos/metabolismo , Bovinos , Suplementos Nutricionais , Método Duplo-Cego , Exercício Físico , Feminino , Alimentos Fortificados/análise , Humanos , Pessoa de Meia-Idade , Leite/química , Força Muscular , Músculo Esquelético/química , Desempenho Físico Funcional
14.
Anim Sci J ; 91(1): e13376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32363685

RESUMO

We evaluated the effects of replacement of heading stage harvested timothy silage with early-harvested orchardgrass-perennial ryegrass mixed (OP) silage while maintaining or reducing concentrate input on dry matter intake (DMI), milk production, nutrient digestibility, and N balance in dairy cows. Nine multiparous Holstein cows were used in a replicated 3 × 3 Latin square design with three dietary treatments: TYL, a diet containing timothy silage where forage-to-concentrate ratio (FC) was 50:50; OPL, a diet containing OP silage where FC ratio was 50:50; and OPH, a diet containing OP silage where FC ratio was 60:40. We observed that an equal replacement of timothy with OP silage increased DMI, milk yield, milk protein production, and nutrient digestibility but decreased milk fat content (TYL versus OPL). We observed that replacing timothy with OP silage while reducing concentrate input increased milk fat and protein yield, nutrient digestibility, and feed efficiency and reduced urinary N loss with no effect on DMI or milk fat content (TYL versus OPH). These results show that replacing timothy with OP silage can be a good approach to improve milk production, feed efficiency, and N utilization and reduce concentrate input. However, milk fat depression should be considered when an equal substitution is performed.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Dieta/veterinária , Digestão/fisiologia , Lactação/fisiologia , Leite , Poaceae , Silagem , Animais , Indústria de Laticínios , Feminino , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Leite/metabolismo
15.
J Dairy Sci ; 103(7): 6533-6556, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32389476

RESUMO

The objective of this study was to investigate the effect of 2 gradual weaning programs and 2 locations of solid feed within individual calf pens on feed intake, growth, and behavior of calves fed milk by an automated milk feeder. Using a 2 × 2 factorial design, 60 female calves were randomly assigned to 1 of 2 weaning treatments and 1 of 2 solid feed placement treatments. Calves were assigned to a continuous gradual weaning program (CG) or a multi-step gradual weaning program (MG). Calves assigned to the CG treatment had their milk allocation reduced in small, equal increments from 12.5 L/d on d 43 to 2 L/d on d 56. Calves assigned to the MG treatment were offered 10 L/d on d 43 to 45, 8 L/d on d 46 to 49, 6 L/d on d 50 to 52, and 3 L/d on d 53 to 56. Solid feed was placed either at the front of the pen adjacent (ADJ) to where the automated milk feeder offered milk or at the back of the pen on the opposite (OPP) side from where the milk was offered. All calves were offered 12.5 L/d of milk replacer from d 2 to 42, fresh solid feed (5% chopped wheat straw mixed with 95% calf starter pellet) from d 5 onward, and ad libitum water starting d 0. Calves were weaned from d 43 to 56 and additionally monitored from d 57 to 70. No interactions of effects of weaning and feed location treatment were detected. Both MG and CG calves had similar water and solid feed consumption, blood ß-hydroxybutyrate concentrations, and behavior. By design, calves on the CG treatment consumed greater amounts of milk during the weaning phase than MG treatment calves (6.7 vs. 6.3 L/d), which resulted in milk drinking behavior differing between the treatments during the weaning phase. Although average daily gain and body weights were similar between treatments, MG calves had greater middle girth gain during wk 7 compared with CG calves (0.6 vs. 0.3 cm/d). Calves on the ADJ treatment consumed 16.7% more solid feed and 0.55 L/d more milk during the preweaning phase compared with OPP treatment calves. In all 3 phases, ADJ treatment calves consumed more water than OPP treatment calves. The ADJ calves spent more time consuming solid feed during the 10-wk period. The ADJ treatment calves had 10% greater average daily gain compared with OPP treatment calves during the preweaning phase. Overall, the results indicate that both gradual weaning treatments resulted in similar performance and behavior. However, placement of solid feed next to the milk source was demonstrated to increase feed, water, and milk intake during the preweaning stage, contributing to greater growth.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Ingestão de Alimentos , Comportamento Alimentar , Leite/metabolismo , Ácido 3-Hidroxibutírico/sangue , Animais , Peso Corporal , Bovinos/sangue , Bovinos/crescimento & desenvolvimento , Indústria de Laticínios , Dieta/veterinária , Feminino , Distribuição Aleatória , Desmame
16.
J Dairy Sci ; 103(7): 6588-6599, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32389482

RESUMO

Mechanical forces during machine milking of dairy cows evoke circulatory impairment of the teat tissue that may affect the teats' defense mechanisms against mastitis pathogens. Ample research describes dimensional changes of different teat traits after machine milking, whereas reports that describe changes in blood circulation of dairy cows' teats are limited. Therefore, the objectives of this study were to (1) describe changes in teat blood circulation that occur after pre-milking teat stimulation and machine milking and (2) study the effect of 2 different milking liners on machine milking-induced changes in teat blood flow. In a randomized trial, Holstein dairy cows were stratified by parity, stage of lactation, and average daily milk yield during the previous week, and allocated to 1 of 2 treatment groups. Treatment consisted of 1 milking observation with either a round or multisided concave milking liner. Teat scans were taken of the left front and the right hind teats using power Doppler ultrasonography. Imaging occurred before pre-milking udder preparation (T1), after completion of pre-milking udder preparation but before milking-unit attachment (T2), and immediately after unit detachment (T3). Perfusion intensity measurements from teat scans were performed with a commercially available software program. Data from 109 cows were analyzed. A general linear mixed model showed differences in perfusion intensity between time points. Least squares means (95% confidence intervals) for T1, T2, and T3, respectively, were 0.035% (0.026-0.047), 0.124% (0.093-0.164), and 0.095% (0.073-0.124). Conversely, no statistically significant differences between treatment groups were observed. We conclude that teat blood circulation is subjected to several influences, including inherent circulatory regulation mechanisms, as well as extrinsic factors such as machine milking. Future research is warranted to decipher the magnitude of their influence and to further our understanding of how these changes relate to the susceptibility to intramammary infection and milking performance.


Assuntos
Mastite Bovina/prevenção & controle , Leite/metabolismo , Animais , Bovinos , Indústria de Laticínios/instrumentação , Feminino , Lactação , Análise dos Mínimos Quadrados , Modelos Lineares , Glândulas Mamárias Animais/diagnóstico por imagem , Mastite Bovina/diagnóstico por imagem , Paridade , Fenótipo , Gravidez , Software , Ultrassonografia/veterinária
17.
PLoS One ; 15(5): e0232824, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384114

RESUMO

Zambia is still facing undernutrition and micronutrient deficiencies despite fortification and supplementation programmes stressing the need for additional solutions. Fermented foods have the potential to improve nutrient intake and, therefore, could have an important role in food based recommendations (FBRs) to ensure adequate intake of nutrients for optimal health of populations. Secondary dietary intake data was used in Optifood, a linear programming software to develop FBRs, for children aged 1-3 and 4-5 years in Mkushi district of Zambia. Three scenarios per age group were modeled to determine FBRs based on: (1) FBRs based on local available foods (2) FBR and Mabisi, a fermented milk beverage, and (3) FBR with Munkoyo, a cereal fermented beverage. The scenarios were compared to assess whether addition of Mabisi or Munkoyo achieved a better nutrient intake. FBRs based on only locally available non-fermented foods did not meet ≥70% of recommended nutrient intake (RNI) for calcium, fat, iron and zinc, so-called problem nutrients. The addition of Munkoyo to the FBRs did not reduce the number of problem nutrients, but after adding Mabisi to the FBR's only iron (67% of RNI) in the 1-3 year age group and only zinc (67% of RNI) in the 4-5 year age group remained problem nutrients. Mabisi, a fermented milk product in combination with the local food pattern is a good additional source of nutrients for these age groups. However, additional nutrition sensitive and cost-effective measures would still be needed to improve nutrient intake, especially that of iron and zinc.


Assuntos
Grão Comestível/metabolismo , Alimentos e Bebidas Fermentados , Leite/metabolismo , Estado Nutricional , Animais , Cálcio na Dieta/metabolismo , Criança , Pré-Escolar , Dieta , Ingestão de Energia/fisiologia , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Ferro/metabolismo , Masculino , Micronutrientes , Nutrientes/metabolismo , Necessidades Nutricionais , Recomendações Nutricionais , Zâmbia/epidemiologia
18.
J Dairy Sci ; 103(6): 5200-5214, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253035

RESUMO

Pasture-based production systems typically require highly fertile, healthy, and robust genetics, with greater emphasis on milk solids (MSo; kg of fat + protein) production as opposed to milk yield. This study assessed milk production, production efficiency, reproductive performance, body weight (BW), body condition score, and functional traits in 3 different dairy cow genotypes: Holstein-Friesian (HF), Jersey × Holstein-Friesian (JEX), and Norwegian Red × (Jersey × Holstein-Friesian) (3-way). The 3 genotypes were rotationally grazed on 4 different grazing treatments after calving in spring and were stocked at a rate of 2.75 cows/ha. Holstein-Friesian cows produced higher daily and total milk yields compared with JEX and 3-way cows (5,718 vs. 5,476 and 5,365 kg/cow, respectively). However, JEX and 3-way cows had higher milk fat and protein contents (4.86 and 4.75%, respectively, for JEX and 3.87 and 3.88%, respectively, for 3-way) compared with HF (4.52 and 3.72%), resulting in similar MSo yield for JEX and HF (469 and 460 kg/cow) and slightly lower MSo yield for 3-way (453 kg/cow) compared with JEX. As parity increased, milk and MSo yield per cow increased. Reproductive performance was not significantly different between the 3 genotypes, which had similar 24-d submission rates, 6-wk pregnancy rates, and overall pregnancy rates over the 4-yr period. No difference in calving difficulty, incidence of mastitis, or incidence of lameness was observed among the 3 genotypes. Body weight was significantly different among all 3 genotypes, with HF being the heaviest followed by 3-way and JEX (530, 499, and 478 kg, respectively), and 3-way cows had a higher body condition score throughout lactation compared with HF and JEX cows. The differences in BW coupled with similar MSo production resulted in JEX cows having the highest production efficiency (4.58 kg of MSo/kg of metabolic BW), 3-way cows being intermediate (4.30 kg of MSo/kg of metabolic BW), and HF cows having the lowest (4.16 kg of MSo/kg of metabolic BW). In conclusion, HF herds with poor reproductive performance and low milk fat and protein contents are likely to benefit considerably from crossbreeding with Jersey, and all herds are likely to benefit in terms of production efficiency. However, where herd performance, particularly in relation to reproductive performance, is comparable with HF in the current study, crossbreeding with Jersey or Norwegian Red is unlikely to lead to significant improvements in overall herd performance.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Métodos de Alimentação/veterinária , Fertilidade , Leite/metabolismo , Reprodução , Animais , Peso Corporal , Dieta/veterinária , Feminino , Glicolipídeos/análise , Glicoproteínas/análise , Lactação , Leite/química , Fenótipo , Gravidez
19.
J Dairy Sci ; 103(6): 5131-5142, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253043

RESUMO

We evaluated the effects of commercially available fatty acid (FA) supplements containing palmitic (C16:0) and stearic acid (C18:0) on nutrient digestibility and production responses of dairy cows. Thirty-six mid-lactation (146 ± 55 d in milk) multiparous Holstein cows were randomly assigned to twelve 3 × 3 balanced truncated Latin squares, with 3 treatments and 2 consecutive 35-d periods, with the final 5 d used for sample and data collection. Treatments were (1) a control diet containing no supplemental FA (CON), (2) a control diet supplemented with a commercially available C16:0 supplement (PA), and (3) a control diet supplemented with a commercially available C16:0 and C18:0 supplement (MIX). Supplements were fed at 1.5% dry matter and replaced soyhulls in CON. The statistical model included the random effect of cow nested within square and the fixed effects of treatment, period, square, and their interactions. Preplanned contrasts were (1) overall effect of FA treatments [CON vs. the average of the FA treatments (FAT); 1/2 (PA + MIX)], and (2) effect of FA supplement (PA vs. MIX). Treatment had no effects on dry matter intake, body weight, or body weight change. Compared with CON, FAT decreased digestibilities of total FA and 18-carbon FA but did not affect dry matter and neutral detergent fiber digestibility. Compared with MIX, PA increased dry matter and neutral detergent fiber digestibilities by 3.6 and 4.8 percentage units, respectively. The PA also increased total FA and 18-carbon FA digestibilities but did not alter 16-carbon FA digestibility compared with MIX. Using a Lucas test, we estimated apparent digestibility coefficients of 0.768 and 0.553 for the PA and MIX supplements, respectively. Compared with CON, FAT increased milk yield and tended to increase energy-corrected milk, but did not affect yield of milk fat or milk protein. The PA increased energy-corrected milk and milk fat yield but had no effect on milk protein yield compared with MIX. Our results indicate that dairy cows producing around 45 kg of milk respond better to a FA supplement enriched in C16:0 compared with a supplement containing both C16:0 and C18:0, which is likely due in part to PA increasing FA and neutral detergent fiber digestibility compared with MIX.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais/análise , Lactação/efeitos dos fármacos , Leite/metabolismo , Ácido Palmítico/farmacologia , Ácidos Esteáricos/farmacologia , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão/efeitos dos fármacos , Feminino , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Leite/química , Proteínas do Leite/metabolismo , Nutrientes/metabolismo , Distribuição Aleatória
20.
J Dairy Sci ; 103(6): 5019-5029, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278555

RESUMO

This study investigated the effects of Lactobacillus plantarum WW-fermented skim milk (FSM) on the physiques of rats fed a high-fat diet and the mechanism of lipid lowering. Sprague-Dawley rats were randomly divided into a normal diet group (A), a high-fat diet group (B), a skim milk diet group (C), and an L. plantarum WW FSM diet group (D). After 12-wk feeding, we found that treatment with L. plantarum WW FSM could significantly alleviate symptoms in the pathological group. Meanwhile, high-throughput sequencing analysis showed that L. plantarum WW FSM also had a certain regulatory effect on the intestinal microorganisms in rats, which can increase the number of lactic acid bacteria and Bacteroides in the intestine. More importantly, real-time quantitative PCR and Western blot analysis showed that the probiotic was also involved in the expression of genes related to fat metabolism, especially the PPARB and CEBPB genes. Our study supports the hypothesis that the WW strain of L. plantarum could be a potential probiotic to be used in functional foods to alter lipid metabolism and reduce cholesterol levels.


Assuntos
Produtos Fermentados do Leite/microbiologia , Dieta Hiperlipídica , Lactobacillus plantarum/metabolismo , Leite/microbiologia , Animais , Intestinos/microbiologia , Metabolismo dos Lipídeos , Masculino , Leite/metabolismo , Probióticos/metabolismo , Ratos , Ratos Sprague-Dawley
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