1,721,215 research outputs found
Interaction between inflammation and metabolism in periparturient dairy cows
No full textA large body of work has been conducted to elucidate the link between the loss of viability, sensitivity to pro-inflammatory mediators and the impairment of antimicrobial functions affecting the innate immune cells, the occurrence of uncontrolled inflammations, and the sudden alteration of the metabolism during the transition from pregnancy to lactation in highproducing dairy cows. Despite this massive effort, a clear link is still missing. The intent of this review is to summarize our current knowledge on the subject and attempt to propose a link. In the first part of this review we provide an overview of the physiological adaptation during the transition from pregnancy to lactation focusing on the alterations affecting the innate immune system and the inflammation occurring during this phase. In the second part of the review, we propose a relationship between the function of the innate immune system, the inflammatory conditions, and the metabolism in dairy cows during the transition from pregnancy to lactation with the intent to elucidate the driving cause of immune alterations occurring in this phase. In the third and final part, we review some novel dietary strategies to optimize the function of the innate immunity in dairy cows describing their mode of action and their applicability as an aid for dairy cows during the peripartal phase
Cows with feed restriction–induced hyperketonemia early postpartum have a different immunometabolic profile than healthy cows or cows with inflammatory disorders
Full text linkImmune activation and subsequent inflammation lead to difficult transitions from pregnancy to lactation. Whether postpartum hyperketonemia can occur independently of immune activation remains controversial. Our objective was to compare immunometabolic profiles in blood serum from healthy cows, healthy feed-restricted cows, and cows with naturally occurring inflammatory disorders. Multiparous Holsteins (n = 32) were fed a dry period diet until parturition. After parturition, all cows were fed a lactation diet at ad libitum intake until 5 DIM. At 4 DIM, cows underwent a thorough physical examination by a veterinarian and were classified as healthy (n = 15) or having at least 1 periparturient disorder or disease (n = 17), which were inflammatory conditions. Healthy cows were assigned to a control ad libitum-fed group (CON; n = 6) or to a group subjected to 50% feed restriction beginning at d 5 (FR; n = 9) and continuing until diagnosis of clinical ketosis or d 14, when they were returned to ad libitum DMI. The periparturient inflammatory disorders (PID; n = 17) group consisted of cows with metritis, retained placenta, foot and leg problems, or mastitis. During the dry period, the serum ratio of albumin:globulin tended to be lower and the concentration of β-carotene was lower for cows destined to be sick than for cows that were healthy postpartum. At d −1 prepartum, haptoglobin and globulin tended to be greater for cows that were sick postpartum than for healthy cows. The albumin:globulin ratio and creatinine at d −1 tended to be lower for sick cows than for healthy cows. At d 1 postpartum, cows that were sick tended to have greater BHB and had lower Zn, albumin, and retinol than healthy cows. Aspartate aminotransferase tended to be greater for sick cows than for healthy cows. At d 7 (during feed restriction but before diagnosis of clinical ketosis), glucose and cholesterol were lower, and nonesterified fatty acids and BHB were greater, in FR cows than in PID cows. Concentration of Ca tended to be lower for cows in FR and PID than for CON cows. Albumin concentration and the ratio of albumin:globulin were lower for PID cows than for FR cows, whereas haptoglobin was greater for PID than for FR. Paraoxonase was lower for cows in FR and PID than for CON. Activity of γ-glutamyltransferase was greater for cows in FR and PID than for CON cows. Bilirubin tended to be greater for cows in FR and PID compared with CON. Retinol tended to be lower for cows with disorders and lower for PID than FR. β-Carotene was greater for FR cows than for PID cows. The liver functionality index, a measure of cow resilience in the transition period, showed the lowest value in PID and the highest in CON, with FR intermediate. Overall, healthy cows with feed restriction–induced hyperketonemia showed little evidence for involvement of inflammation
Variation factors of paraoxonase in blood and in HDL lipoproteins in dairy cow
No full textParaoxonase-1 (PON) is an antioxidant enzyme synthesized by liver and mainly associated with high density lipoproteins (HDL). Aim of this study was to investigate the alterations of PON1 activity in plasma
(pPON) or bound to HDL (HDL-PON) in relation to inflammatory conditions and physiological stages. Between -30 to +300 days from calving, 9 cows were monitored for metabolic and inflammatory profiles,
milk yield, body condition score and feed intake. Cows were divided in 2 groups based on their response to postpartum inflammatory stimulus (high and low Liver Functionality Index: HI-LFI and LO-LFI). pPON
decreased after calving (P<0.05) and was directly correlated with milk yield (r=0.48; P<0.01), albumins and other indirect indexes of negative acute phase proteins (-APP: cholesterol and retinol binding protein). On the contrary, pPON was inversely related with the +APP (haptoglobin, ceruloplasmin) and related indexes (bilirubin, ROM). The correlation between pPON and HDL-PON was low. After calving, the HI-LFI vs LO-LFI group had higher –APP and pPON levels, lower HDL-PON level and displayed better performances. Overall results demonstrated
that pPON has a similar behavior in comparison to –APP, confirming previous data. The results suggested that pPON activity could represent an useful marker to assess the severity of postpartum inflammatory phenomena
and their consequences
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Changes of metabolic conditions around calving affect oxidative stress and acute phase protein in pluriparous dairy cows
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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