Alterations of the Lipid Metabolome in Dairy Cows Experiencing Excessive Lipolysis Early Postpartum

<div><p>A decrease in insulin sensitivity enhances adipose tissue lipolysis helping early lactation cows counteracting their energy deficit. However, excessive lipolysis poses serious health risks for cows, and its underlying mechanisms are not clearly understood. The present study used targeted ESI-LC-MS/MS-based metabolomics and indirect insulin sensitivity measurements to evaluate metabolic alterations in the serum of dairy cows of various parities experiencing variable lipolysis early postpartum. Thirty (12 primiparous and 18 multiparous) cows of Holstein Friesian and Simmental breeds, fed the same diet and kept under the same management conditions, were sampled at d 21 postpartum and classified as low (n = 10), medium (n = 8), and high (n = 12) lipolysis groups, based on serum concentration of nonesterified fatty acids. Overall, excessive lipolysis in the high group came along with impaired estimated insulin sensitivity and characteristic shifts in acylcarnitine, sphingomyelin, phosphatidylcholine and lysophospholipid metabolome profiles compared to the low group. From the detected phosphatidylcholines mainly those with diacyl-residues showed differences among lipolysis groups. Furthermore, more than half of the detected sphingomyelins were increased in cows experiencing high lipomobilization. Additionally, strong differences in serum acylcarnitines were noticed among lipolysis groups. The study suggests an altered serum phospholipidome in dairy cows associated with an increase in certain long-chain sphingomyelins and the progression of disturbed insulin function. In conclusion, the present study revealed 37 key metabolites as part of alterations in the synthesis or breakdown of sphingolipids and phospholipids associated with lowered estimated insulin sensitivity and excessive lipolysis in early-lactating cows.</p></div

A bar graph showing the top 15 metabolites correlating with RQUICKI.

<p>The X-axis indicates Pearson correlation coefficients.</p

Concentrations of lysophosphatidylcholines, phosphatidylcholines and sphingomyelins in the serum of cows differing in the degree of lipolysis and parity.

<p>Concentrations of lysophosphatidylcholines, phosphatidylcholines and sphingomyelins in the serum of cows differing in the degree of lipolysis and parity.</p

A bar graph showing the top 15 metabolites correlating with nonesterified fatty acids.

<p>The X-axis indicates Pearson correlation coefficients.</p

Serum amino acids, biogenic amines, and sum of hexoses in cows with low (n = 10), medium (n = 8), and high (n = 12) fat mobilization after calving.

<p>Serum amino acids, biogenic amines, and sum of hexoses in cows with low (n = 10), medium (n = 8), and high (n = 12) fat mobilization after calving.</p

Table_1_School students' burdens and resources after 2 years of COVID-19 in Austria: a qualitative study using content analysis.docx

IntroductionThe mental health of young people has been severely affected by the COVID-19 pandemic and the measures associated with it. Mental health symptoms increased across various domains during the pandemic and subjective wellbeing decreased.MethodsThis study examined the burdens and resources of Austrian school students (M = 16.63 years old) in the third year of the pandemic and compared them descriptively with the burdens and resources identified in a comparative study in 2021. A cross-sectional online survey with open-ended questions from April to May 2022 provided data that was analyzed using qualitative content analysis. A sub-sample of N = 214 was selected from the larger sample. This sub-sample is representative for the Austrian population aged 15–19 in terms of gender and migrant background.ResultsAnalysis of the open-ended questions showed that concerns about the pandemic and the burdens of the measures were no longer on young people's minds at the time of the survey in 2022. On the other hand, stress at school was increasing and the opening of schools and the resumption of face-to-face teaching were challenging for respondents. While resuming social contacts and leisure activities was mentioned as a resource by many respondents, some also expressed a desire for more time off and a retreat into coping strategies such as sleeping more or avoiding problems.DiscussionOur findings suggest that there is a need for low-threshold support from teachers and parents to help students catch up on missed lessons and to empathize with the mas they make the transition back to “old normal”.</p