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1.
J Dairy Sci ; 107(5): 2832-2849, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37949403

RESUMO

We investigated how concentrate feeding during the last 21 d of pregnancy affects reticular pH, inflammatory response, dry matter (DM) intake, and production performance of dairy cows. We hypothesized that adding concentrates to dairy cows' diet before calving reduces the decrease in reticular pH postpartum and thus alleviates inflammatory response. We also hypothesized that prepartum concentrate feeding increases DM intake postpartum and consequently improves milk performance. Two feeding experiments were conducted using a randomized complete block design. In each experiment, 16 multiparous Finnish Ayrshire cows were paired based on parity, expected calving date, body weight, and milk yield of the previous lactation. Within the pairs, cows were randomly allocated on one of the 2 dietary treatments 21 d before expected calving. In experiment 1 (Exp1), diets were ad libitum feeding of grass silage as a sole feed or supplemented with increasing amounts of concentrate offered separately (increased to 4 kg/d by d -7). In experiment 2 (Exp2), diets were ad libitum feeding of a total mixed ration containing either grass silage, barley straw, and rapeseed meal (64%, 28%, and 8% on DM basis, respectively) or grass silage, barley straw, and cereal-based concentrate mixture (49%, 29%, and 30% on DM basis, respectively). Following calving, all the cows were fed similarly and observed until d 56 postpartum. Feed intake and milk yield were recorded daily, and reticular pH was monitored continuously by reticular pH bolus. Blood samples were collected at the beginning of the experiments, 7 d before the expected calving date, 1 d (in Exp1) or 5 d (in Exp2), 10 d, and 21 d postpartum. In Exp1, concentrate feeding increased metabolizable energy intake and tended to increase DM and crude protein intake prepartum. Moreover, prepartum concentrate feeding increased the concentrations of plasma ß-hydroxybutyrate and insulin, but differences in nonesterified fatty acids, glucose, or acute phase proteins were not observed. After calving, prepartum diet did not affect DM or nutrient intake, plasma energy metabolites, or milk production in Exp1. Although prepartum concentrate feeding increased reticular pH on the first day of lactation, it elevated plasma concentrations of serum amyloid-A and haptoglobin postpartum in the grass silage-based diet. In Exp2, adding concentrates to the diet based on a mixture of grass silage and straw did not affect prepartum DM intake or plasma concentrations of nonesterified fatty acids, glucose, or insulin. Adding concentrates to prepartum diet increased plasma concentration of ß-hydroxybutyrate before calving as in Exp1. After calving, prepartum concentrate feeding increased DM and nutrient intake during the second week of lactation in Exp2, but no effects were observed thereafter. In contrast to our hypothesis, prepartum concentrate feeding decreased reticular pH after calving in Exp2, but no differences in inflammatory markers were observed. Based on this study, close-up concentrate feeding in diets based on grass silage with or without straw does not alleviate the decrease in reticular pH or mitigate inflammatory response postpartum.

2.
Reprod Fertil Dev ; 29(5): 931-939, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28442044

RESUMO

The aims of the present study was to develop and describe a transvaginal ultrasound-guided biopsy method for luteal tissue in the porcine and to evaluate the effects of the method on the reproductive tract, ovarian status and pregnancy status. Biopsies were performed in four multiparous sows on Days 9 and 15 of three consecutive oestrous cycles; the size and histological composition of the samples obtained were evaluated and the reproductive tract of the sows was monitored. Furthermore, biopsies were performed in 26 multiparous sows on Days 10 and 13 after insemination, and the pregnancy rate, gestation length and subsequent litter size were evaluated. RNA was extracted from the samples obtained and the quality and quantity were determined. Altogether, 76 biopsies were performed and 38 samples were obtained. Compared with sows from which no samples were obtained (n=6), sows from which one or more samples were obtained (n=24) were older (parity 5.0±2.8 vs 2.2±0.4, mean±s.d.), heavier (290±26 vs 244±27kg) and had higher back fat (11.4±2.7 vs 6.4±2.5mm; P<0.05 for all). No effect of the biopsies (P>0.05) was observed on the cyclicity and reproductive organs of the sows, or on corpus luteum diameter on Day 13 (8.9±1.0 vs 9.2±1.1mm), pregnancy rate (95% vs 96%), gestation length (115±1 vs 115±1 days) and subsequent litter size (12.7±2.5 vs 13.3±2.8) between sows from which samples were obtained and those from which no samples were obtained. The samples obtained had a diameter of 1mm and contained heterogeneous tissue with various cell types. The RNA quantity was 520±160µg per sample and the RNA integrity number was 8.5±1.0. In conclusion, an ultrasound-guided biopsy method for ovarian tissue, which can be used for gene expression studies, was established in the porcine. No effect on corpus luteum function was found.


Assuntos
Corpo Lúteo/patologia , Reprodução/fisiologia , Ultrassonografia de Intervenção , Animais , Corpo Lúteo/diagnóstico por imagem , Corpo Lúteo/metabolismo , Feminino , Expressão Gênica , Biópsia Guiada por Imagem , Gravidez , Taxa de Gravidez , Suínos
3.
Sci Rep ; 10(1): 441, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949191

RESUMO

The establishment of the intestinal microbiota is critical for the digestive and immune systems. We studied the early development of the rectal microbiota in horse, a hindgut fermenter, from birth until 7 days of age, by qPCR and 16S rRNA gene amplicon sequencing. To evaluate initial sources of the foal microbiota, we characterised dam fecal, vaginal and oral microbiotas. We utilised an amplicon sequence variant (ASV) pipeline to maximise resolution and reproducibility. Stringent ASV filtering based on prevalence and abundance in samples and controls purged contaminants while preserving intestinal taxa. Sampled within 20 minutes after birth, rectal meconium contained small amounts of diverse bacterial DNA, with a profile closer to mare feces than mouth. 24 hours after birth, rectum was colonised by Firmicutes and Proteobacteria, some foals dominated by single genera. At day 7, the rectal genera were still different from adult feces. The mare vaginal microbiota contributed to 24 h and 7 day microbiotas. It contained few lactobacilli, with Corynebacterium, Porphyromonas, Campylobacter and Helcococcus as the most abundant genera. In the oral mucosa, Gemella was extremely abundant. Our observations indicate that bacteria or bacterial components are present in the intestine immediately after birth, but the newborn microbiota changes rapidly.


Assuntos
Microbioma Gastrointestinal , Animais , Animais Recém-Nascidos , Fezes/microbiologia , Feminino , Dosagem de Genes , Cavalos , Boca/microbiologia , RNA Ribossômico 16S/genética , Vagina/microbiologia
4.
Mucosal Immunol ; 6(5): 942-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23299615

RESUMO

Due to a limited range of immunoglobulin (Ig) genes, cattle and several other domestic animals rely on postrecombinatorial amplification of the primary repertoire. We report that activation-induced cytidine deaminase (AID) is strongly expressed in the fetal bovine ileal Peyer's patch and spleen but not in fetal bone marrow. The numbers of IGHV (immunoglobulin heavy chain variable) mutations correlate with AID expression. The mutational profile in the fetuses is similar to postnatal and immunized calves, with targeting of complementarity-determining region (CDR) over framework region (FR), preference of replacement over silent mutations in CDRs but not in FRs, and targeting of the AID hotspot motif RGYW/WRCY. Statistical analysis indicates negative selection on FRs and positive selection on CDRs. Our results suggest that AID-mediated somatic hypermutation and selection take place in bovine fetuses, implying a role for AID in the diversification of the primary antibody repertoire in the absence of exogenous antigens.


Assuntos
Citidina Desaminase/metabolismo , Nódulos Linfáticos Agregados/metabolismo , Baço/metabolismo , Motivos de Aminoácidos/genética , Animais , Diversidade de Anticorpos/genética , Formação de Anticorpos/genética , Bovinos , Seleção Clonal Mediada por Antígeno , Regiões Determinantes de Complementaridade/genética , Citidina Desaminase/genética , Feto , Íleo/citologia , Cadeias Pesadas de Imunoglobulinas/genética , Mutação/genética , Hipermutação Somática de Imunoglobulina
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