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1.
J Dairy Sci ; 106(4): 2651-2666, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36653292

RESUMO

Chronic postpartum uterine infection detrimentally affects subsequent fertility. Nonsteroidal anti-inflammatory drugs (NSAID) are used to alleviate pain and treat inflammatory conditions in transition dairy cows with varying success. To screen the efficacy of NSAID in the absence of animal experiments, we have established an in vitro model to study uterine inflammation. Inflammation was induced in cultured bovine endometrial epithelial cells by challenging cells with an inflammation cocktail: lipopolysaccharide and proinflammatory cytokines, interleukin-1ß (IL1ß) and tumor necrosis factor α (TNFα). Release of the inflammation markers, serum amyloid A (SAA) and α-1-acid glycoprotein (αAGP), was measured by ELISA. Concentration of these markers was used to indicate the effectiveness in dampening inflammation of 5 NSAID: meloxicam, flunixin meglumine, aspirin, ketoprofen, and tolfenamic acid. Three NSAID, meloxicam, flunixin meglumine, and tolfenamic acid, were successful at dampening the release of SAA and αAGP into cell-culture supernatant, and the corresponding treated cells were selected for down-stream mRNA expression analysis. Expression of 192 genes involved in regulation of inflammatory pathways were investigated using Nanostring. Of the genes investigated, 81 were above the mRNA expression-analysis threshold criteria and were included in expression analysis. All SAA genes investigated (SAA2, SAA3, M-SAA3.2) were upregulated in response to the inflammation cocktail, relative to mRNA expression in control cells; however, AGP mRNA expression was below the expression analysis threshold and was, therefore, excluded from analysis. Treatment with NSAID downregulated genes involved in regulating chemokine signaling (e.g., CXCL2, CXCR4, CXCL5, and CXCL16) and genes that regulate the eicosanoid pathway (e.g., LTA4H, PTGS2, PLA2G4A, and PTGDS). Of the 5 NSAID investigated, meloxicam, flunixin meglumine, and tolfenamic acid are recommended for further investigation into treatment of postpartum uterine inflammation. The results from this study confirm the immunomodulatory properties of the endometrial epithelium in response to inflammatory stimuli and suggest that NSAID may be beneficial in alleviating uterine inflammation.


Assuntos
Doenças dos Bovinos , Endometrite , Feminino , Bovinos , Animais , Meloxicam , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Inflamação/veterinária , Endometrite/tratamento farmacológico , Endometrite/veterinária , RNA Mensageiro/metabolismo , Células Epiteliais/metabolismo , Doenças dos Bovinos/tratamento farmacológico
2.
J Dairy Sci ; 105(6): 5519-5533, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35465990

RESUMO

A strong adaptive immune response has been reported to have positive effects on fertility; therefore, we investigated antibody- and cell-mediated adaptive immune responses (AMIR and CMIR, respectively) and their associations with reproductive phenotypes using a population of animals that differed in their estimated genetic merit for fertility traits (fertility breeding value; FertBV). Holstein-Friesian heifers (n = 528) grazed on pasture in 4 herds based on age. These herds included 277 heifers of positive (POS) FertBV and 251 of negative (NEG) FertBV. The adaptive immune response (IR) was evaluated before puberty at 7.5 mo of age and used to rank animals as high, average, or low for AMIR, CMIR, and overall IR (combined CMIR and AMIR). The animals were studied from 12 wk of age through to the end of their second lactation to measure growth, puberty, and timing and success of fertility phenotypes, including those related to ovulation and pregnancy. Initial analysis indicated no difference in fertility outcomes between cows ranked as high or average for AMIR (n = 55, n = 407, respectively), CMIR (n = 87, n = 354, respectively), and IR (n = 29, n = 470, respectively), so these groups were pooled as HiAv-IR. Proportions of heifers of POS FertBV were similar within HiAv and low categories across AMIR (0.52 and 0.58, respectively), CMIR (0.51 and 0.59, respectively), and IR (0.53 and 0.48, respectively). Heifers with HiAv-IR had a greater average daily weight gain from 13 to 52 wk of age (661 g, 95% confidence interval 652, 669 vs. 619 g, 95% confidence interval 591, 647) and tended to be younger at puberty (371 d, 95% confidence interval 366, 377 vs. 385 d, 95% confidence interval 369, 401) than low-IR heifers. Low-CMIR cows of a NEG FertBV had a >40 d longer calving to first ovulation interval during their first lactation compared with HiAv-CMIR NEG FertBV cows. Low-CMIR cows also had decreased pregnancy rates at both 3 wk (25% ± 7% vs. 42% ± 3%; least squares means ± standard error) and 6 wk (33% ± 7% vs. 54% ± 3%; least squares means ± standard error) into the seasonal breeding period during their first lactation, compared with HiAv-CMIR cows. In summary, although the number of POS and NEG FertBV cows was similar in each immune group; interaction effects between FertBV and immune ranking on reproductive phenotypes are evident when cows were ranked by the overall IR. There were also associations between dairy cows' CMIR ranking and ability to return to estrus and become pregnant early in the breeding period, which will have benefits in seasonal breeding systems.


Assuntos
Fertilidade , Reprodução , Imunidade Adaptativa , Animais , Bovinos , Feminino , Fertilidade/genética , Lactação , Fenótipo , Gravidez , Reprodução/genética
3.
J Dairy Sci ; 105(2): 1754-1767, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34799104

RESUMO

Peripartum metabolism and subsequent reproductive performance of dairy cows are linked, with maladaptation over the transition period associated with poor reproductive success. A herd of seasonal calving, grazing dairy cows was established that differed in their genetic merit for fertility traits. The heifers were produced by a customized mating program to achieve a 10-percentage point divergence in the New Zealand fertility breeding value (FertBV) as follows: +5 FertBV (POS) versus -5% FertBV (NEG), while also limiting divergence in other breeding values, including body weight, body condition score, and milk production. In this study, we aimed to characterize differences in metabolic, mineral, and metabolic stress marker profiles during their first postpartum transition period as primiparous heifers and to examine if animals with longer postpartum anestrous intervals (PPAI; more than 66 d compared with less than 35 d) had greater metabolic dysfunction. Blood was sampled at -21, -14, -7, 0, 4, 7, 10, 14, 17, 21, 28, and 35 d relative to calving in 455 primiparous cows and plasma analyzed. The NEG cows had lower concentrations of both plasma nonesterified fatty acids and ß-hydroxybutyrate at d 7 compared with POS cows. Detailed temporal profiling of various metabolic, mineral, and metabolic stress markers was undertaken in a subset of cows (n = 70). Cows were selected retrospectively to create 4 groups in a 2 × 2 factorial design with either a POS or NEG FertBV and either a short (19-35 d) or long (66-131 d) PPAI. The NEG cows tended, on average, to have lower nonesterified fatty acids and ß-hydroxybutyrate concentrations compared with POS cows across the transition period. Mean body weight and body condition score was greatest in NEG cows when compared with the POS cows and an interaction with day demonstrated this only occurred precalving. They also had indications of improved liver health precalving, with higher albumin-to-globulin ratios and lower bilirubin concentrations. Concentrations of aspartate aminotransferase were lower, and the Na-to-Cl ratio was greater in cows with a long versus a short PPAI at d 28 and d 35 after calving, potentially because of cows with a short PPAI (19-35 d) returning to estrous during this time. Magnesium concentrations were lower in NEG cows with a short PPAI from d 21 onwards, indicating NEG cows may metabolically respond to estrous differently than POS cows. The NEG-long PPAI cows had greater gamma-glutamyl transferase concentrations from calving until d 28 and lower bilirubin concentrations throughout the transition period. Together, the results demonstrate significant effects of FertBV on peripartum metabolic status. However, most of the markers tested returned to reference intervals within 4 d after calving or remained within those intervals for the whole transition period, indicating relatively minor biological effects of FertBV on transition period adaptation. The profound differences in reproductive performance among the groups was not explained by underlying differences in metabolic responses during the transition period.


Assuntos
Lactação , Leite , Ácido 3-Hidroxibutírico , Animais , Bovinos , Eletrólitos , Ácidos Graxos não Esterificados , Feminino , Fertilidade/genética , Fígado , Minerais , Período Pós-Parto , Estudos Retrospectivos
4.
J Dairy Sci ; 105(3): 2669-2698, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34998544

RESUMO

The physiology of the dairy cow while transitioning from pregnancy to lactation is complex, with multifactorial processes studied extensively for the role they play in manifestation of disease along with associated economic losses and compromised animal welfare. Manuscripts outlining associations among nutrition, production, physiology, and genetics variables and transition cow disorders are common in literature, with blood analytes that are central to energy metabolism (e.g., nonesterified fatty acids; NEFA, ß-hydroxybutyrate; BHB) often reported. Immunity and inflammation have increasingly been explored in the pathogenesis and persistence of disorders, with cytokines and acute phase proteins well documented. However, most of these studies have involved cows fed total mixed rations, which may not always reflect profiles of blood analytes and other physiological indicators of transition cow health in grazing cows consuming fresh pasture. Considering the comparatively lesser characterization of these analytes and markers in pasture-based, seasonal-calving dairy cows, we compiled a database consisting of 2,610 cow lactations that span 20 yr of transition cow research in New Zealand. Using this database, analyte profiles from approximately 28 d precalving to 35 d postcalving were identified in dairy cows with a range of genetics, milk production potentials, and pasture-based farm management systems. These profiles characterize changes in energy reserves and metabolism (NEFA, BHB, glucose, insulin, growth hormone, insulin-like growth factor-1, leptin, body condition score, body weight), liver function (globulin, aspartate aminotransferase, glutamate dehydrogenase, gamma-glutamyl transpeptidase, bilirubin, cholesterol, liver triacylglycerides), protein metabolism (albumin, total protein, albumin:globulin ratio, creatinine, urea, creatine kinase), mineral balance (calcium, magnesium, phosphate, potassium, sodium, chloride, bicarbonate), inflammation (IL-1ß, IL-6, haptoglobin, reactive oxygen species, total antioxidant capacity), and uterine health (polymorphonuclear cells, macrophage cells, vaginal discharge score). Temporal changes are generally consistent with previously characterized homeorhetic changes experienced by the dairy cow during the transition from pregnancy to lactation in both pastoral and housed systems. Some of the profiles had not previously been presented for pastoral systems, or in some cases, presented for either system. Our results indicate that moderate-yielding dairy cows undergo similar homeorhetic changes to high-yielding housed cows; however, differences in diet composition result in greater BHB concentrations than expected, based on their milk production and NEFA concentrations. In addition, most cows were able to transition to a state of higher energy requirement following calving, albeit with an increased metabolic challenge in the liver, and only a small percentage of cows were classified with severe hepatic lipidosis or severe hyperketonemia. Increases in metabolic function of the liver were accompanied by changes in indicators of the immune system and changes in mineral balance that, combined, probably reflect the innate response to the transition from gestation to lactation.


Assuntos
Doenças dos Bovinos , Leite , Ácido 3-Hidroxibutírico , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Dieta/veterinária , Metabolismo Energético , Ácidos Graxos não Esterificados , Feminino , Inflamação/metabolismo , Inflamação/veterinária , Lactação/fisiologia , Leite/metabolismo , Período Pós-Parto/fisiologia , Gravidez , Estações do Ano
5.
J Dairy Sci ; 104(9): 10382-10398, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34176625

RESUMO

New Zealand's Fertility Breeding Value (FertBV) is reported as the percentage of a sire's daughters that calve in the first 42 d of the seasonal calving period and is an estimate of genetic merit for fertility for dairy cattle. Reproductive physiology, milk production, and changes in body weight and body condition score of 2 groups of cows divergent in FertBV (+5.0%: POS; -5.1%: NEG) were characterized during their first 2 lactations. Cows grazed fresh pasture and were managed in a seasonal calving system; they were bred by artificial insemination on observed estrus for the entire breeding period (98 d in lactation 1 and 76 d in lactation 2). During lactation 1, all animals were primiparous and were randomly allocated to 1 of 2 herds, ensuring each herd was balanced for FertBV and expected calving date. During lactation 2, cows that became pregnant during lactation 1 were managed as 1 herd. Cows not inseminated in the first 42 d of the breeding season were examined for the presence of a corpus luteum and treated with an anestrus program. On average, the interval from calving to ovulation was 19 d longer in lactation 1 and 10 d longer in lactation 2 for NEG FertBV cows. The percent of cows submitted for artificial insemination after 21 d (i.e., submission rate) was 38 and 25 percentage points greater in the POS FertBV cows during lactations 1 and 2, respectively. Pregnancy rate from 42 d of breeding was 33 and 30 percentage points greater, respectively. There was no effect of FertBV on vaginal discharge score postcalving; however, POS FertBV cows had a 50% lower risk of having subclinical endometritis (polymorphonuclear leukocytes >7%) 42 d postcalving. Interactions between FertBV and month relative to calving identified that NEG FertBV cows were fatter (greater body condition score) in the month before calving, but thinner between 3 and 5 mo postcalving. There was no effect of FertBV on lactation length, estimated 270-d milk yields, or daily milk, fat, or protein yields, and only small effects on milk fat and protein percentage across the lactations. In summary, the POS FertBV cows had superior uterine health, a shorter calving to ovulation interval, a greater submission rate, and a greater pregnancy rate earlier in the breeding season when compared with the NEG FertBV cohort. Based on these results, these may be useful phenotypes to include in genetic selection indices.


Assuntos
Fertilidade , Reprodução , Animais , Bovinos/genética , Feminino , Fertilidade/genética , Lactação , Leite , Fenótipo , Gravidez , Reprodução/genética , Estações do Ano
6.
J Dairy Sci ; 104(11): 11955-11972, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34419282

RESUMO

Transition dairy cows experience a decline in immune function that increases the risk of peripartum disease. One strategy to improve peripartum immune function involves the use of a commercially available cytokine: bovine granulocyte-colony stimulating factor, with the addition of polyethylene glycol to increase duration of effectiveness. Treatment with Imrestor (15 mg pegbovigrastim; Elanco) one week before expected calving date (d -7) and again on the day of calving (d 0) was previously reported to increase the neutrophil number and improve neutrophil function; as a result, the incidence of clinical mastitis was reduced. We conducted 2 experiments over consecutive years to investigate the effect of a lower dose rate (half or quarter dose rate) of Imrestor in grazing dairy cattle and reduced administration frequency: one dose instead of the recommended 2. White blood cell counts were measured to determine changes in relative cell populations in response to treatment. Neutrophil function was assessed by measuring myeloperoxidase activity. Imrestor treatment increased the numbers of neutrophils, band cells, lymphocytes, and monocytes until 14 d postcalving in a dose-dependent manner; it also increased neutrophil myeloperoxidase activity. One dose of Imrestor increased white blood cell counts and myeloperoxidase activity, but the timing, degree, and duration of the response were different relative to the recommended 2 doses and were also dependent upon when Imrestor treatment was given. One dose at d -7 relative to expected calving date did not have a lasting effect postcalving, whereas one dose only on d 0 caused a delayed effect relative to cows that received 2 doses. There was no effect of Imrestor on milk yield or on blood indicators of transition cow health. A lower dose rate of Imrestor or a single dose of Imrestor on the day of calving may be sufficient to improve neutrophil function during the early postpartum in grazing dairy cows. Large-scale field studies are required to determine whether the smaller response from lower dose rates or the timing of the immunological response to drug delivery affect animal health in early lactation.


Assuntos
Fator Estimulador de Colônias de Granulócitos , Lactação , Animais , Bovinos , Feminino , Leite , Neutrófilos , Proteínas Recombinantes
7.
J Dairy Sci ; 104(3): 3707-3721, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455798

RESUMO

This study investigated the hypothesis that dairy heifers divergent in genetic merit for fertility traits differ in the age of puberty and reproductive performance. New Zealand's fertility breeding value (FertBV) is the proportion of a sire's daughters expected to calve in the first 42 d of the seasonal calving period. We used the New Zealand national dairy database to identify and select Holstein-Friesian dams with either positive (POS, +5 FertBV, n = 1,334) or negative FertBV (NEG, -5% FertBV, n = 1,662) for insemination with semen from POS or NEG FertBV sires, respectively. The resulting POS and NEG heifers were predicted to have a difference in average FertBV of 10 percentage points. We enrolled 640 heifer calves (POS, n = 324; NEG, n = 316) at 9 d ± 5.4 d (± standard deviation; SD) for the POS calves and 8 d ± 4.4 d old for the NEG calves. Of these, 275 POS and 248 NEG heifers were DNA parent verified and retained for further study. The average FertBV was +5.0% (SD = 0.74) and -5.1% (SD = 1.36) for POS and NEG groups, respectively. Heifers were reared at 2 successive facilities as follows: (1) calf rearing (enrollment to ∼13 wk of age) and (2) grazier, after 13 wk until 22 mo of age. All heifers wore a collar with an activity sensor to monitor estrus events starting at 8 mo of age, and we collected weekly blood samples when individual heifers reached 190 kg of body weight (BW) to measure plasma progesterone concentrations. Puberty was characterized by plasma progesterone concentrations >1 ng/mL in at least 2 of 3 successive weeks. Date of puberty was defined when the first of these samples was >1 ng/mL. Heifers were seasonally bred for 98 d starting at ∼14 mo of age. Transrectal ultrasound was used to confirm pregnancy and combined with activity data to estimate breeding and pregnancy dates. We measured BW every 2 wk, and body condition and stature at 6, 9, 12, and 15 mo of age. The significant FertBV by day interaction for BW was such that the NEG heifers had increasingly greater BW with age. This difference was mirrored with the significant FertBV by month interaction for average daily gain, with the NEG heifers having a greater average daily gain between 9 and 18 mo of age. There was no difference in heifer stature between the POS and NEG heifers. The POS heifers were younger and lighter at puberty, and were at a lesser mature BW, compared with the NEG heifers. As a result, 94 ± 1.6% of the POS and 82 ± 3.2% of the NEG heifers had reached puberty at the start of breeding. The POS heifers were 20% and 11% more likely to be pregnant after 21 d and 42 d of breeding than NEG heifers (relative risk = 1.20, 95% confidence interval of 1.03-1.34; relative risk = 1.11, 95% confidence interval of 1.01-1.16). Results from this experiment support an association between extremes in genetic merit for fertility base on cow traits and heifer reproduction. Our results indicate that heifer puberty and pregnancy rates are affected by genetic merit for fertility traits, and these may be useful phenotypes for genetic selection.


Assuntos
Fertilidade , Maturidade Sexual , Animais , Bovinos/genética , Feminino , Fertilidade/genética , Nova Zelândia , Fenótipo , Gravidez , Taxa de Gravidez , Reprodução , Maturidade Sexual/genética
8.
Br J Nutr ; 123(5): 592-600, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-31779715

RESUMO

Exercise modifies energy intake (EI) in adolescents with obesity, but whether this is mediated by the exercise-induced energy deficit remains unknown. The present study examined the effect of exercise with and without dietary replacement of the exercise energy expenditure on appetite, EI and food reward in adolescents with obesity. Fourteen 12-15-year-old adolescents with obesity (eight girls; Tanner 3-4; BMI 34·8 (sd 5·7) kg/m2; BMI z score 2·3 (sd 0·4)) randomly completed three experimental conditions: (i) rest control (CON); (ii) 30-min cycling (EX) and (iii) 30-min cycling with dietary energy replacement (EX + R). Ad libitum EI was assessed at lunch and dinner, and food reward (Leeds Food Preference Questionnaire) before and after lunch. Appetite was assessed at regular intervals. Lunch, evening and total EI (excluding the post-exercise snack in EX - R) were similar across conditions. Lunch and total EI including the post-exercise snack in EX + R were higher in EX - R than CON and EX; EX and CON were similar. Total relative EI was lower in EX (6284 (sd 2042) kJ) compared with CON (7167 (sd 2218) kJ; P < 0·05) and higher in EX + R (7736 (sd 2033) kJ) compared with CON (P < 0·001). Appetite and satiety quotients did not differ across conditions (P ≥ 0·10). Pre-meal explicit liking for fat was lower in EX compared with CON and EX + R (P = 0·05). There was time by condition interaction between EX and CON for explicit wanting and liking for fat (P = 0·01). Despite similar appetite and EI, adolescents with obesity do not adapt their post-exercise food intake to account for immediate dietary replacement of the exercise-induced energy deficit, favouring a short-term positive energy balance.


Assuntos
Apetite/fisiologia , Ciclismo/fisiologia , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Obesidade Infantil/fisiopatologia , Adaptação Fisiológica , Adolescente , Criança , Feminino , Humanos , Masculino , Obesidade Infantil/terapia , Saciação , Resultado do Tratamento
9.
Appetite ; 146: 104506, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678149

RESUMO

The present study manipulated the delay between exercise and test meal to investigate its effect on energy intake, appetite sensations and food reward in adolescents with obesity. Fifteen adolescents with obesity randomly completed 3 experimental sessions: i) rest without exercise (CON); ii) 30 min of exercise 180 min before lunch (EX-180); iii) 30 min of exercise 60 min before lunch (EX-60). Ad libitum energy intake was assessed at lunch and dinner, and food reward (LFPQ) assessed before and after lunch. Appetite sensations were assessed at regular intervals. Absolute energy intake was not different between conditions despite a 14.4% lower intake in EX-60 relative to CON. Lunch relative energy intake (REI: energy intake - exercise-induced energy expenditure) was higher in CON compared with EX-60 (p < 0.001). Lunch fat intake was lower in EX-60 compared with CON (p = 0.01) and EX-180(p = 0.02). Pre-lunch hunger in CON was lower than EX-180 (p = 0.02). Pre-lunch prospective food consumption and desire to eat were lower in CON compared with both exercise conditions (p = 0.001). A significant condition effect was found for explicit liking for high-fat relative to low-fat foods before lunch (p = 0.03) with EX-60 being significantly lower than EX-180 (p = 0.001). The nutritional and food reward adaptations to exercise might be dependent on the timing of exercise, which is of importance to optimize its effect on energy balance in adolescents with obesity. CLINICAL TRIAL REFERENCE: NCT03807609.


Assuntos
Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Refeições/fisiologia , Obesidade Infantil/fisiopatologia , Fatores de Tempo , Adaptação Fisiológica , Adolescente , Apetite , Criança , Metabolismo Energético , Exercício Físico/psicologia , Feminino , Humanos , Fome , Masculino , Refeições/psicologia , Obesidade Infantil/psicologia , Descanso , Recompensa
10.
J Dairy Sci ; 103(3): 2662-2676, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31864735

RESUMO

Precalving feeding level and body condition score (BCS) alter postcalving energy balance and oxidant status of dairy cows. We hypothesized that the reported benefits of a controlled restriction precalving depend on precalving BCS. The objective was to identify alterations in activity and intermediates of the hepatic one-carbon metabolism, transsulfuration, and tricarboxylic acid pathways. Twenty-eight pregnant and nonlactating grazing dairy cows of mixed age and breed (Friesian, Friesian × Jersey) were randomly allocated to 1 of 4 treatment groups in a 2 × 2 factorial design: 2 prepartum BCS categories [4.0 (thin, BCS4) and 5.0 (optimal, BCS5); 10-point scale], by managing cows in late lactation to achieve the 2 groups at dry-off, and 2 levels of energy intake during the 3 wk preceding calving (75 or 125% of estimated requirements), obtained via allowance (m2/cow) of fresh pasture composed of mostly perennial ryegrass and white cover. Average (± standard deviation) age was 6 ± 2, 6 ± 3, 5 ± 1, and 7 ± 3 yr for BCS4 fed 75 and 125%, and BCS5 fed 75 and 125%, respectively. Breed distribution (average ± standard deviation) for the 4 groups was 79 ± 21, 92 ± 11, 87 ± 31, and 74 ± 23% Friesian, and 17 ± 20, 8 ± 11, 13 ± 31, and 25 ± 23% Jersey. Liver tissue was collected by biopsy at -7, 7, and 28 d relative to calving. Tissue was used for 14C radio-labeling assays to measure betaine-homocysteine S-methyltransferase, 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR), and cystathionine-ß-synthase (CBS) activity. Liver metabolomics was undertaken using a targeted liquid chromatography with tandem mass spectrometry-based profiling approach. After initial liquid chromatography separation, mass spectra were acquired under both positive and negative ionization, whereas multiple reaction monitoring was used to measure target compound signal response (peak area count). Enzyme activity and metabolite peak area count were normalized with the homogenate protein concentration. Repeated measures analysis of variance via PROC MIXED in SAS (SAS Institute Inc., Cary, NC), with BCS, feeding, and time as fixed effects, and cow as random effect was used. All enzyme activities were affected by time, with betaine-homocysteine S-methyltransferase activity peaking at 7 d, whereas CBS and MTR activity decreased postpartum. Overall, thin cows had greater MTR activity, whereas cows fed 125% requirements had greater CBS activity. An interaction was detected between BCS and feeding for CBS activity, as thin cows fed 125% of requirements had greater overall activity. Compared with liver from BCS4 cows, BCS5 cows had overall greater betaine, glycine, butyrobetaine/acetylcholine, serine, and taurine concentrations. The same metabolites, plus choline and N-N-dimethylglycine, were overall greater in liver of cows fed 75% compared with those fed 125% of requirements. An interaction of BCS and feeding level was detected for the aforementioned metabolites plus methionine, cystathionine, cysteinesulfinate, and hypotaurine, due to greater overall concentrations in BCS5 cows fed 75% of requirements compared with other groups. Overall, differences in hepatic enzyme activity and intermediate metabolites suggest that both BCS and feeding level can alter the internal antioxidant system (e.g., glutathione and taurine) throughout the periparturient period. Further studies are needed to better understand potential mechanisms involved.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Betaína-Homocisteína S-Metiltransferase/metabolismo , Bovinos/fisiologia , Cistationina beta-Sintase/metabolismo , Ingestão de Energia , Metabolismo Energético , Animais , Antioxidantes/metabolismo , Carbono/metabolismo , Bovinos/genética , Colina/metabolismo , Dieta/veterinária , Feminino , Homocisteína/metabolismo , Lactação , Fígado/enzimologia , Metabolômica , Metionina/metabolismo , Estado Nutricional , Período Pós-Parto , Gravidez
11.
J Dairy Sci ; 103(1): 723-736, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31668440

RESUMO

Synthetic zeolites are used to control the availability of dietary minerals (e.g., Ca, Mg, and P) in dairy cows. Due to calcium demand increasing with lactation onset, most cows become hypocalcemic immediately postpartum, which likely contributes to poorer immune function because calcium is important for immune cell signaling. To overcome postpartum hypocalcemia, we fed transition cows synthetic zeolite A (sodium aluminosilicate) precalving and hypothesized that it would alter calcium and thus neutrophil function during the transition period. Multiparous Holstein-Friesian cows in late gestation were randomly allocated to an untreated control group (n = 10) or a treatment group in which each cow received 500 g of zeolite A daily (n = 10) for 14 d prior to the expected calving date (actual duration = 17 ± 3 d prepartum). The cows grazed pasture, and each was supplemented with 2 kg/d of maize silage (dry matter basis), with or without zeolite, until calving. Blood samples for neutrophil isolation and analysis of plasma indicators of mineral status, energy status, liver function, and inflammation were collected pretreatment (covariate; d -19); on d -14 and -7 precalving; on the day of calving (d 0); and on d 1, 4, 7, and 28 postcalving. Neutrophils were isolated and gene expression was analyzed using microfluidic gene expression arrays. Neutrophil respiratory burst was assessed using stimulation with phorbol 12-myristate 13-acetate and flow cytometry. Plasma calcium and phosphorus revealed a treatment by time interaction; cows offered zeolite had greater plasma calcium concentrations at d 0, 1, and 4 postcalving and plasma phosphorus concentrations were lower in zeolite-treated cows during the precalving period until d 1 postcalving compared with control animals. Zeolite treatment downregulated neutrophil gene expression of CXCR4 and S100A8 and tended to lower gene expression for other immune mediators (CXCR1, IFNG, S100A12, and S100A9) compared with the control. Zeolite treatment did not affect neutrophil respiratory burst or expression of the other genes investigated. Plasma concentrations of cytokine IL-6 were reduced with zeolite treatment, which was most evident immediately postcalving (d 0, 1, and 7). Overall, feeding zeolite precalving had few effects on neutrophil gene expression and function; however, the lower gene expression of neutrophil inflammatory mediators may be due to altered availability of dietary minerals prepartum and indicates that zeolite A may control inflammation during the transition period.


Assuntos
Suplementos Nutricionais , Regulação da Expressão Gênica/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Zeolitas/administração & dosagem , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Feminino , Lactação/fisiologia , Leite/metabolismo , Neutrófilos/metabolismo , Período Pós-Parto , Gravidez , Silagem , Zeolitas/síntese química , Zeolitas/farmacologia
12.
J Dairy Sci ; 103(11): 10530-10546, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32861495

RESUMO

Hypocalcemia is a common metabolic disorder of transition dairy cows that is considered a gateway disease, increasing the risk of other health disorders and reducing cow performance. Clinical milk fever is associated with long periods of recumbency, and it is plausible that cows experiencing non-paretic hypocalcemia may spend more time lying; hence, lying behavior and activity measures may be useful in identifying at-risk cows. The objective of this study was to describe associations among blood calcium (Ca) status at calving and lying behavior and activity measures during the transition period in grazing dairy cows. Blood was sampled on the day of calving (d 0), and d 1, 2, 3, and 4 postcalving, and analyzed for total plasma Ca concentration. Twenty-four multiparous Holstein-Friesian and Holstein-Friesian × Jersey grazing dairy cows were classified, retrospectively, as clinically hypocalcemic (CLIN; blood Ca ≤ 1.4 mmol/L at 1 or more consecutive samplings within 48 h postcalving, but without parturient paresis). These cows were pair-matched (using milk production potential from their estimated breeding value for milk protein, mean body weight at wk -5 and -6 precalving, and, where possible, parity) with 24 cows classified as subclinically hypocalcemic (SUB; blood Ca > 1.4 and < 2.0 mmol/L at 2 consecutive samplings within 48 h postcalving), and 24 cows classified as normocalcemic (NORM; blood Ca ≥ 2.0 mmol/L at 3 consecutive samplings within 72 h postcalving). Lying behavior and activity were monitored using triaxial accelerometers from -21 to +35 d relative to calving. Data were summarized to calculate daily lying time (h/d), daily number of lying bouts (LB; no./d), mean LB duration (min/bout), and the number of steps taken (steps/d). On d 0, the CLIN group were less active and spent approximately 2.6 h longer lying than the SUB and NORM groups, particularly between 0200 and 1400 h. On d 0, the NORM group had fewer LB (16.3/d) than the SUB and CLIN groups (18.2 and 19.2/d, respectively). These differences in behavior were no longer detected 2 d postcalving, and no further differences were observed. The day before calving, the CLIN group spent 1.4 h longer lying down than did the SUB and NORM groups. Further, the relative change in steps from a precalving baseline period (d -14 to -7) until d 0 was positively, linearly associated with blood Ca concentration within 24 h postcalving. Future work should consider daily and temporal changes in behavior in individual cows to determine the potential for these measures to allow early detection of hypocalcemia.


Assuntos
Comportamento Animal , Doenças dos Bovinos/etiologia , Hipocalcemia/veterinária , Descanso , Animais , Peso Corporal , Cálcio/sangue , Bovinos/sangue , Doenças dos Bovinos/metabolismo , Feminino , Herbivoria , Hipocalcemia/etiologia , Lactação , Leite/metabolismo , Paridade , Postura , Gravidez , Estudos Retrospectivos
13.
J Dairy Sci ; 103(12): 12140-12157, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33069407

RESUMO

Until recently, animal behavior has been studied through close and extensive observation of individual animals and has relied on subjective assessments. Wearable technologies that allow the automation of dairy cow behavior recording currently dominate the precision dairy technology market. Wearable accelerometers provide new opportunities in animal ethology using quantitative measures of dairy cow behavior. Recent research developments indicate that quantitative measures of behavior may provide new objective on-farm measures to assist producers in predicting, diagnosing, and managing disease or injury on farms and allowing producers to monitor cow comfort and estrus behavior. These recent research developments and a large increase in the availability of wearable accelerometers have led to growing interest of both researchers and producers in this technology. This review aimed to summarize the studies that have validated lying behavior derived from accelerometers and to describe the factors that should be considered when using leg-attached accelerometers and neck-worn collars to describe lying behavior (e.g., lying time and lying bouts) in dairy cows for research purposes. Specifically, we describe accelerometer technology, including the instrument properties and methods for recording motion; the raw data output from accelerometers; and methods developed for the transformation of raw data into meaningful and interpretable information. We highlight differences in validation study outcomes for researchers to consider when developing their own experimental methodology for the use of accelerometers to record lying behaviors in dairy cows. Finally, we discuss several factors that may influence the data recorded by accelerometers and highlight gaps in the literature. We conclude that researchers using accelerometers to record lying behaviors in dairy cattle should (1) select an accelerometer device that, based on device attachment and sampling rate, is appropriate to record the behavior of interest; (2) account for cow-, farm-, and management-related factors that could affect the lying behaviors recorded; (3) determine the appropriate editing criteria for the accurate interpretation of their data; (4) support their chosen method of recording, editing, and interpreting the data by referencing an appropriately designed and accurate validation study published in the literature; and (5) report, in detail, their methodology to ensure others can decipher how the data were captured and understand potential limitations of their methodology. We recommend that standardized protocols be developed for collecting, analyzing, and reporting lying behavior data recorded using wearable accelerometers for dairy cattle.


Assuntos
Acelerometria/veterinária , Bovinos , Indústria de Laticínios , Dispositivos Eletrônicos Vestíveis/veterinária , Animais , Comportamento Animal , Indústria de Laticínios/métodos , Estro , Feminino , Leite , Monitorização Fisiológica/veterinária , Estudantes
14.
Phys Rev Lett ; 123(18): 182501, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31763910

RESUMO

Backward-angle meson electroproduction above the resonance region, which was previously ignored, is anticipated to offer unique access to the three quark plus sea component of the nucleon wave function. In this Letter, we present the first complete separation of the four electromagnetic structure functions above the resonance region in exclusive ω electroproduction off the proton, ep→e^{'}pω, at central Q^{2} values of 1.60, 2.45 GeV^{2}, at W=2.21 GeV. The results of our pioneering -u≈-u_{min} study demonstrate the existence of a unanticipated backward-angle cross section peak and the feasibility of full L/T/LT/TT separations in this never explored kinematic territory. At Q^{2}=2.45 GeV^{2}, the observed dominance of σ_{T} over σ_{L}, is qualitatively consistent with the collinear QCD description in the near-backward regime, in which the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes: universal nonperturbative objects only accessible through backward-angle kinematics.

15.
World J Urol ; 37(10): 2109-2117, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30652213

RESUMO

OBJECTIVE: To evaluate the accuracy in histologic grading of MRI/US image fusion biopsy by comparing histopathology between systematic biopsies (SB), targeted biopsies (TB) and the combination of both (SB + TB) with the final histopathologic outcomes of radical prostatectomy specimens. MATERIALS AND METHODS: Retrospective, multicentric study of 443 patients who underwent SB and TB using MRI/US fusion technique (Urostation® and Trinity®) prior to radical prostatectomy between 2010 and 2017. Cochran's Q test and McNemar test were conducted as a post hoc test. Uni-multivariable analyses were performed on several clinic-pathological variables to analyze factors predicting histopathological concordance for targeted biopsies. RESULTS: Concordance in ISUP (International Society of Urological Pathology) grade between SB, TB and SB + TB with final histopathology was 49.4%, 51.2%, and 63.2% for overall prostate cancer and 41.2%, 48.3%, and 56.7% for significant prostate cancer (ISUP grade ≥ 2), respectively. Significant difference in terms of concordance, downgrading and upgrading was found between SB and TB (ISUP grade ≥ 2 only), SB and SB + TB, TB and SB + TB (overall ISUP grade and ISUP grade ≥ 2) (p < 0.001). Total number of cores and previous biopsies were significant independent predictive factors for concordance with TB technique. CONCLUSION: In this retrospective study, combination of SB and TB significantly increased concordance with final histopathology despite a limited additional number of cores needed.


Assuntos
Biópsia Guiada por Imagem/métodos , Imagem por Ressonância Magnética Intervencionista , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Ultrassonografia de Intervenção , Idoso , Humanos , Masculino , Imagem Multimodal , Gradação de Tumores , Prostatectomia/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
J Dairy Sci ; 102(3): 2708-2713, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639015

RESUMO

Reducing enteric methane (CH4) production and improving feed conversion efficiency of dairy cows is of high importance. Residual feed intake (RFI) is one measure of feed efficiency, with low RFI animals being more efficient in feed conversion. Enteric CH4 is an important source of digestible energy loss in ruminants and, because research in beef cattle has reported a positive relationship between RFI and daily CH4 production, we hypothesized that low RFI dairy heifers, which are more feed efficient, would produce less CH4/d. We measured the daily methane production (g of CH4/d), methane yield [g of CH4/kg of dry matter intake (DMI)], and CH4 per kilogram of body weight (BW) gain for 56 heifers (20-22 mo old) in a 2 × 2 factorial arrangement: factors included 2 breeds (Holstein-Friesian and Jersey; n = 28/breed), with equal numbers of animals previously determined as being either high [+2.0 kg of dry matter (DM)/d] or low RFI (-2.1 kg of DM/d; n = 28/RFI category). All heifers were commingled and offered unrestricted access to the same diet of dried alfalfa cubes. Between RFI categories, heifers did not differ in BW or BW gain but low RFI heifers had 9.3 and 10.6% lower DMI and DMI/kg of BW, respectively, than high RFI heifers. Similarly, RFI category did not affect CH4/d or CH4/kg of BWg, but CH4/kg of DMI was higher in low RFI heifers because of their lower DMI. These results might reflect more complete digestion of ingested feed in the more efficient, low RFI heifers, consistent with previous reports of greater apparent digestibility of organic matter. Holstein-Friesian heifers were heavier and consumed more total DM than Jersey heifers, but breed did not affect DMI/kg of BW or BWg. Jersey heifers produced less CH4/d, but not CH4/kg of DMI or CH4/kg of BWg. We detected no interaction between breed and RFI category in any of the variables measured. In conclusion, differences in RFI in dairy heifers did not affect daily CH4 production (g/d); however, low RFI heifers had a greater CH4 yield (g/kg of DMI) on a high forage diet.


Assuntos
Ração Animal , Bovinos/metabolismo , Metano/biossíntese , Animais , Peso Corporal , Dieta/veterinária , Digestão , Feminino , Medicago sativa , Especificidade da Espécie
17.
J Dairy Sci ; 102(9): 8559-8570, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301843

RESUMO

Because of its high yield and the ability of cows to graze it in situ, fodder beet (FB) has become a popular crop in grazing systems, particularly for nonlactating cows. Due to its high sugar content, however, the transition to FB must be managed carefully to avoid rumen acidosis and associated metabolic dysfunction. The initial consumption of FB reduces ruminal pH; however, it is unclear whether this affects liver metabolism and results in systemic inflammation, as has been reported during subacute ruminal acidosis from high-grain diets. We used a quantitative case study approach to undertake additional measurements on a project demonstrating the effects of FB on urinary nitrogen excretion. The objective of our component, therefore, was to determine whether the inclusion of high rates of FB in the diet of nonlactating cows changed indicators of hepatic metabolism relative to a standard diet for nonlactating grazing cows. During the nonlactating period, multiparous, pregnant Holstein-Friesian cows were randomly assigned (n = 15 per treatment) to either pasture (8 kg of DM/cow per day) with corn silage (4 kg of DM/cow per day; PA) or transitioning onto an FB diet (8 kg of DM/cow per day) with pasture silage (4 kg of DM/cow per day; BT) over 14 d. Blood was sampled and the liver was biopsied during the adaptation period and after 7 d of full diet allocation. The hepatic expression of genes involved in peroxisomal oxidation was increased in cows adapting to FB, whereas the expression of genes involved in mitochondrial oxidation was increased when cows were on their full allocation of FB. These results indicate changes to fatty acid metabolism with FB consumption. Expression of 2 genes involved in the unfolded protein response was greater during the adaptation period in cows consuming FB, potentially reflecting negative effects of transitioning onto the FB diet on hepatic metabolism. Interestingly, expression of genes involved in the methionine cycle was increased in the BT cows. We hypothesize that this is a result of FB betaine absorption, although it is unclear to what extent betaine escapes ruminal degradation. While on the full diet allocation, there were lower serum concentrations of markers of hepatic stress in BT cows and no difference in expression of genes involved in oxidative stress compared with pasture-fed cows. However, there was an increase in plasma haptoglobin concentrations, indicative of an acute inflammatory response in BT cows. From this case study, we conclude that the results indicate no negative effects of the FB diet on liver metabolism and, possibly, positive effects on hepatic function. It appears, therefore, that the transition of nonlactating cows onto an FB diet can be managed to minimize the negative effects of the high sugar intake. Further research on the amount of betaine that escapes ruminal degradation in cows consuming FB would be of value to better understand whether betaine reduces liver damage in dairy cows consuming FB.


Assuntos
Beta vulgaris , Bovinos/metabolismo , Dieta/veterinária , Fígado/metabolismo , Ração Animal/efeitos adversos , Animais , Antioxidantes/análise , Beta vulgaris/efeitos adversos , Beta vulgaris/metabolismo , Ácidos Graxos/metabolismo , Feminino , Expressão Gênica , Concentração de Íons de Hidrogênio , Lactação/fisiologia , Leite/química , Nitrogênio/urina , Gravidez , Rúmen/química , Zea mays
18.
J Dairy Sci ; 102(8): 7371-7384, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202660

RESUMO

Lying behavior and activity may provide useful information for the prediction of an imminent calving and the health of transition dairy cows; however, it is important first to understand what constitutes typical lying behavior and activity because this has not been defined for grazing dairy cows during the transition period. Our objective was to describe changes in lying behavior and activity in grazing dairy cows during the transition period using varying phenotypes typical of commercial dairy herds under grazing systems. Behavior data from IceTag or IceQube (IceRobotics, Edinburgh, Scotland) triaxial accelerometers were collected for 310 cow parities from multiparous, mixed-age (mean ± standard deviation; 4.5 ± 1.65 yr), and mixed-breed [Holstein-Friesian (HF), n = 216; and HF × Jersey, n = 94] grazing dairy cows from 4 parent experiments. The IceTags or IceQubes captured lying and activity data during the transition period (-21 to 34 d relative to calving) to allow the calculation of daily lying time (h/d), daily lying bouts (LB; no./d), mean LB duration (min/bout), and the number of steps taken (steps/d). Lying behavior and activity were analyzed using a repeated measures ANOVA during 3 periods: PRE (-21 to -3 d), POST (3 to 21 d), and the day of calving (d 0). Lying time was lower on d 0 (7.25 h/d) compared with PRE and POST lying times (10.3 and 8.58 h/d, respectively), with more frequent LB on d 0 (12.9 no./d) compared with the PRE and POST daily LB (8.15 vs. 7.74 no./d). Cows took more steps POST (4,424 steps/d) compared with d 0 and PRE (4,105 and 2,289 steps/d, respectively). Regression analysis determined that daily lying time decreased substantially from -3 to 0 d (slope = -1.03 ± 0.07 h/d) and from -2 and -1 d for daily LB (slope = 5.09 ± 0.54 no./d), which may be due to the calving event itself but also reflect restlessness. Daily lying time, daily LB, LB duration, and number of steps taken were substantially altered at the time of the calving event in grazing dairy cows. Cows were more active, spent less time lying, and took more steps postcalving compared with precalving, and it appears that this behavior may largely be due to activity associated with twice daily milking. Mean lying behavior and activity measures were more highly variable across individuals than across groups. Information available via activity monitors may contribute to the improvement of individual management of transition dairy cows, and this research provides a benchmark for typical changes in behavior during the transition period in grazing systems.


Assuntos
Comportamento Animal , Bovinos/fisiologia , Indústria de Laticínios , Lactação/fisiologia , Parto/fisiologia , Postura/fisiologia , Animais , Feminino , Leite , Movimento , Gravidez , Escócia , Fatores de Tempo
19.
J Dairy Sci ; 102(12): 11523-11535, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31548070

RESUMO

In theory, a late winter-early spring calving date in temperate grazing systems best matches pasture supply and herd demand, thereby minimizing the need for nonpasture feeds and maximizing profitability. We used a quantitative case study approach to define the effects of season of calving on biophysical and financial performance in a grazing system without the confounding effects of imported feeds (i.e., milk production directly from grazed pasture). A 2-yr production system experiment was established to quantify the effects of changing onset of seasonal calving (i.e., planned start of calving; PSC) from winter (July in the Southern Hemisphere) to spring (October), summer, (January), or autumn (April) on pasture and animal production and profitability. Eighty Holstein-Friesian cows were randomly allocated to 1 of 4 PSC treatments, each of which had a different PSC [mean calving date of January 10 (JAN), April 10 (APR), July 10 (JUL), or October 10 (OCT)]. Data were analyzed for consistency of treatment response over years using ANOVA procedures with year, PSC treatment, and year × PSC treatment interactions as fixed effects. Collated biological data and financial data extracted from a national economic database were used as fixed variables to model the financial performance for the different treatments. A stochastic risk analysis was undertaken, where historical pasture growth and milk price data were used to estimate the probability distributions for stochastic input variables. Gross farm revenue and operating profit per hectare were modeled under 2 scenarios: (A) milk price did not include a premium for milk supplied during the winter, and (B) milk price included a realistic premium for milk supplied in winter. Annual and seasonal pasture growth did not differ between treatments, but the pasture growth (kg of dry matter/ha) and profile of the JUL treatment best matched the lactation nutrient demand profile. In comparison, profiles for JAN, APR, and OCT calving treatments had periods of greater surplus and deficit due to the time of calving and herd demand relative to the pasture growth profile. As a result, the JAN and OCT treatments conserved more pasture as silage and cows consumed a larger proportion of their annual diet as silage. Although the amount of silage conserved and consumed did not differ between the JUL and APR calving treatments, the timing of the silage consumption was different, with silage making up a greater proportion of the diets in the APR treatment 1 to 90 and 91 to 180 d postcalving and being offered to the JUL calving treatment only 271 to 365 d postcalving. As a result of differences in the quantity and proportion of pasture and pasture silage in the lactating diet, the JUL treatment herd tended to produce greater milk, 4% fat-corrected milk, fat, protein, and lactose yields (kg/cow) than the other PSC treatments, which did not differ from each other. Operating expenses per hectare did not differ materially between calving date scenarios, but operating expenses per kilogram of fat-corrected milk and kilogram of fat and protein were 15 to 20% less in the JUL treatment. With or without a realistic winter milk premium, gross farm revenue and operating profit per hectare were greater in the JUL treatment than in the APR treatment, which had greater revenue and profitability than the remaining 2 calving date treatments. In summary, our results indicate that a PSC in late winter is most profitable in a grazing system not importing feed, with or without a realistic price incentive scheme.


Assuntos
Bovinos , Indústria de Laticínios/métodos , Parto , Estações do Ano , Ração Animal/economia , Animais , Indústria de Laticínios/economia , Dieta/veterinária , Feminino , Lactação , Leite , Silagem
20.
J Dairy Sci ; 102(8): 7408-7420, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178180

RESUMO

The high metabolic demand during the transition into lactation places cows at greater risk of metabolic and infectious disease than at any other time in their lactation cycle. Additionally, a change occurs in the innate immune response during this period, which contributes to increased risk of disease. In the current study, we compared the transcriptomes of neutrophils from dairy cows divergent in their metabolic health post-calving. Cows (n = 5 per risk group) were selected from a parent experiment (n = 45 cows). Those with high or low concentrations of plasma nonesterified fatty acids, plasma ß-hydroxybutyrate, and liver triacylglycerol in both wk 1 and 2 were deemed to be at "high risk" (HR) or "low risk" (LR) of metabolic dysfunction, respectively. Circulating neutrophils were isolated at 3 time points during the transition period (d 0 and wk 1 and 4 post-calving), and gene expression was analyzed using RNA sequencing. Differential gene expression between the risk groups was determined using edgeR (http://bioconductor.org), and pathway analysis was conducted using Ingenuity Pathway Analysis (Ingenuity Systems, Qiagen, Valencia, CA). Statistical analysis indicated no interaction between risk and week. Therefore, the overall effect of risk was analyzed across all time points. In total, 3,500 genes were differentially expressed between the HR and LR cows (false discovery rate < 0.05). Of these, 2,897 genes were identified by Ingenuity Pathway Analysis and used for pathway analysis. Of the relevant pathways identified, neutrophils isolated from HR cows showed downregulation of genes involved in the recruitment of granulocytes, interferon signaling, and apoptosis, and upregulation of genes involved in cell survival. The results indicate that metabolically stressed cows had reduced neutrophil function during the peripartum period, highlighting a potential relationship between subclinical metabolic disease and innate immune function that suggests that metabolic health negatively affects the innate immune system and may contribute to the state of immunosuppression during the peripartum period. In this way, the metabolic stress among the HR cows may reduce their ability to combat infection during the transition period.


Assuntos
Bovinos/imunologia , Perfilação da Expressão Gênica/veterinária , Neutrófilos/imunologia , Período Periparto/imunologia , Estresse Fisiológico/imunologia , Ácido 3-Hidroxibutírico/sangue , Animais , Bovinos/genética , Doenças dos Bovinos/imunologia , Ácidos Graxos não Esterificados/sangue , Feminino , Expressão Gênica , Imunidade/genética , Lactação/fisiologia , Fígado/química , Fatores de Risco , Análise de Sequência de RNA/veterinária , Triglicerídeos/análise , Regulação para Cima
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