Blood and liver telomere length, mitochondrial DNA copy number, and hepatic gene expression of mitochondrial dynamics in mid-lactation cows supplemented with l-carnitine under systemic inflammation.

The current study was conducted to examine the effect of l-carnitine (LC) supplementation on telomere length and mitochondrial DNA copy number (mtDNAcn) per cell in mid-lactation cows challenged by lipopolysaccharide (LPS) in blood and liver. The mRNA abundance of 31 genes related to inflammation, oxidative stress, and the corresponding stress response mechanisms, the mitochondrial quality control and the protein import system, as well as the phosphatidylinositol 3-kinase/protein kinase B pathway, were assessed using microfluidics integrated fluidic circuit chips (96.96 dynamic arrays). In addition to comparing the responses in cows with or without LC, our objectives were to characterize the oxidative and inflammatory status by assessing the circulating concentration of lactoferrin (Lf), haptoglobin (Hp), fibrinogen, derivates of reactive oxygen metabolites (dROM), and arylesterase activity (AEA), and to extend the measurement of Lf and Hp to milk. Pluriparous Holstein cows were assigned to either a control group (CON, n = 26) or an LC-supplemented group (CAR; 25 g LC/cow per day; d 42 ante partum to d 126 postpartum (PP), n = 27). On d 111 PP, each cow was injected intravenously with LPS (Escherichia coli O111:B4, 0.5 µg/kg). The mRNA abundance was examined in liver biopsies of d -11 and +1 relative to LPS administration. Plasma and milk samples were frequently collected before and after the challenge. After LPS administration, circulating plasma fibrinogen and serum dROM concentrations increased, whereas AEA decreased. Moreover, serum P4 initially increased by 3 h after LPS administration and declined thereafter irrespective of grouping. The Lf concentrations increased in both groups after LPS administration, with the CAR group showing greater concentrations in serum and milk than the CON group. After LPS administration, telomere length in blood increased, whereas mtDNAcn per cell decreased; however, both remained unaffected in liver. For mitochondrial protein import genes, the hepatic mRNA abundance of the translocase of the mitochondrial inner membrane (TIM)-17B was increased in CAR cows. Moreover, TIM23 increased in both groups after LPS administration. Regarding the mRNA abundance of genes related to stress response mechanisms, 7 out of 14 genes showed group × time interactions, indicating a (local) protective effect due to the dietary LC supplementation against oxidative stress in mid-lactating dairy cows. For mtDNAcn and telomere length, the effects of the LPS-induced inflammation were more pronounced than the dietary supplementation of LC. Dietary LC supplementation affected the response to LPS primarily by altering mitochondrial dynamics. Regarding mRNA abundance of genes related to the mitochondrial protein import system, the inner mitochondrial membrane translocase (TIM complex) seemed to be more sensitive to dietary LC than the outer mitochondrial membrane translocase (TOM complex).

Effects of dietary l-carnitine supplementation on the response to an inflammatory challenge in mid-lactating dairy cows: Hepatic mRNA abundance of genes involved in fatty acid metabolism.

This study aimed at characterizing the effects of dietary l-carnitine supplementation on hepatic fatty acid (FA) metabolism during inflammation in mid-lactating cows. Fifty-three pluriparous Holstein dairy cows were randomly assigned to either a control (CON, n = 26) or an l-carnitine supplemented (CAR; n = 27) group. The CAR cows received 125 g of a rumen-protected l-carnitine product per cow per day (corresponding to 25 g of l-carnitine/cow per day) from d 42 antepartum (AP) until the end of the trial on d 126 postpartum (PP). Aside from the supplementation, the same basal diets were fed in the dry period and during lactation to all cows. In mid lactation, each cow was immune-challenged by a single intravenous injection of 0.5 µg of LPS/kg of BW at d 111 PP. Blood samples were collected before and after LPS administration. The mRNA abundance of in total 39 genes related to FA metabolism was assessed in liver biopsies taken at d -11, 1, and 14 relative to LPS (d 111 PP) and also on d 42 AP as an individual covariate using microfluidics integrated fluidic circuit chips (96.96 dynamic arrays). In addition to the concentrations of 3 selected proteins related to FA metabolism, acetyl-CoA carboxylase α (ACACA), 5' AMP-activated protein kinase (AMPK), and solute carrier family 25 member 20 (SLC25A20) were assessed by a capillary Western blot method in liver biopsies from d -11 and 1 relative to LPS from 11 cows each of CAR and CON. On d -11 relative to LPS, differences between the mRNA abundance in CON and CAR were limited to acyl-CoA dehydrogenase (ACAD) very-long-chain (ACADVL) with greater mRNA abundance in the CAR than in the CON group. The liver fat content decreased from d -11 to d 1 relative to the LPS injection and remained at the lower level until d 14 in both groups. One day after the LPS challenge, lower mRNA abundance of carnitine palmitoyltransferase 1 (CPT1), CPT2, ACADVL, ACAD short-chain (ACADS), and solute carrier family 22 member 5 (SLC22A5) were observed in the CAR group as compared with the CON group. However, the mRNA abundance of protein kinase AMP-activated noncatalytic subunit gamma 1 (PRKAG1), ACAD medium-chain (ACADM), ACACA, and FA binding protein 1 (FABP1) were greater in the CAR group than in the CON group on d 1 relative to LPS. Two weeks after the LPS challenge, differences between the groups were no longer detectable. The altered mRNA abundance before and 1 d after LPS pointed to increased transport of FA into hepatic mitochondria during systemic inflammation in both groups. The protein abundance of AMPK was lower in CAR than in CON before the LPS administration. The protein abundance of SLC25A20 was neither changing with time nor treatment and the ACACA protein abundance was only affected by time. In conclusion, l-carnitine supplementation temporally altered the hepatic mRNA abundance of some genes related to mitochondrial biogenesis and very-low-density lipoprotein export in response to an inflammatory challenge, but with largely lacking effects before and 2 wk after LPS.

Interrelations between the rumen microbiota and production, behavioral, rumen fermentation, metabolic, and immunological attributes of dairy cows.

Different studies have shown a strong correlation between the rumen microbiome and a range of production traits (e.g., feed efficiency, milk yield and components) in dairy cows. Underlying dynamics concerning cause and effect are, however, still widely unknown and warrant further investigation. The aim of the current study was to describe possible functional interrelations and pathways using a large set of variables describing the production, the metabolic and immunological state, as well as the rumen microbiome and fermentation characteristics of dairy cows in early lactation (n = 36, 56 ± 3 d in milk). It was further hypothesized that the feed intake-associated behavior may influence the ruminal fermentation pattern, and a set of variables describing these individual animal attributes was included. Principal component analysis as well as Spearman's rank correlations were conducted including a total of 265 variables. The attained plots describe several well-known associations between metabolic, immunological, and production traits. Main drivers of variance within the data set included milk production and efficiency as well as rumen fermentation and microbiome diversity attributes, whereas behavioral, metabolic, and immunological variables did not exhibit any strong interrelations with the other variables. The previously well-documented strong correlation of production traits with distinct prokaryote groups was confirmed. This mainly included a negative correlation of operational taxonomic units ascribed to the Prevotella genus with milk and fat yield and feed efficiency. A central role of the animals' feed intake behavior in this context could not be affirmed. Furthermore, different methodological and interpretability aspects concerning the microbiome analysis by 16S rRNA gene sequencing, such as the discrepancy between taxonomic classification and functional communality, as well as the comparability with other studies, are discussed. We concluded that, to further investigate the driving force that causes the difference between efficient and inefficient animals, studies including more sophisticated methods to describe phenotypical traits of the host (e.g., rumen physiology, metabolic and genetic aspects) as well as the rumen microbiome (e.g., metagenome, metatranscriptome, metaproteome, and metabolome analysis) are needed.

Influence of conjugated linoleic acids and vitamin E on biochemical, hematological, and immunological variables of dairy cows during the transition period.

The objective of this experiment was to determine the effects of conjugated linoleic acid (CLA) and vitamin E as well as their interaction on biochemical and hematological variables and on leukocyte populations and their functionality. We assigned 59 German Holstein cows between the 2nd and 9th lactation to 4 dietary groups in a 2 × 2 factorial design with the factors CLA and vitamin E. Six weeks before calving the cows had a BCS of 3.7 to provoke a higher risk of developing ketosis, which might impair their immune function. Blood samples for analyses were taken on d -42, -14, -7, -3, 1, 3, 7, 10, 14, 21, 28, 35, 42, 56, and 70 relative to parturition. Furthermore, peripheral blood mononuclear cells were cultured on d -42, -7, 1, 7, 14, 28, and 70 relative to calving. Most variables were characterized by a high variation between d 7 antepartum and d 7 postpartum. Treatments did not elicit any effect, with the exception of vitamin E, which increased serum urea concentrations and decreased monocyte percentages. Haptoglobin, aspartate-aminotransferase, red blood cell count, leukocyte percentage and populations, as well as peripheral blood mononuclear cells were influenced by parity. In conclusion, the impairment of immune function caused by calving was more severe in cows in ≥3rd parity than in younger cows. However, neither vitamin E nor CLA supplementation was successful to stabilize parity or parturition related variance in hematological and immunological traits.

Effects of energy supply and nicotinic acid supplementation on serum anti-oxidative capacity and on expression of oxidative stress-related genes in blood leucocytes of periparturient primi- and pluriparous dairy cows.

The periparturient period is accompanied by metabolic and oxidative stress. Niacin is known to decrease lipolysis but is also reported to have anti-oxidative effects. Therefore, we examined the effects of energy supply and a nicotinic acid (NA) supplementation on anti-oxidative serum parameters and on the expression of oxidative stress-related genes in blood leucocytes of periparturient dairy cows, differing in parity. Twenty-nine pluriparous and 18 primiparous cows were allocated to four different feeding groups 42 days before expected parturition until 100 days postpartum and fed a ration with either a low concentrate proportion of 30% (LC) or a high concentrate proportion of 60% (HC). After parturition, all animals received 30% concentrate which was increased to 50% either within 16 (LC group) or 24 days (HC group). Half of the animals per group were supplemented with 24 g NA per day from 42 days prepartum until 24 days postpartum. All investigated parameters varied significantly over time compared to parturition (p < .05). Ferric reducing ability (FRA) exhibited a nadir before parturition, and the antioxidant enzymes glutathione peroxidase (GPX) and superoxide dismutase (SOD) showed peak activities around parturition. Expression levels of GPX1, SOD2, xanthine dehydrogenase (XDH) and nuclear factor (erythroid-derived 2)-like 2 (NRF2) peaked before calving. The concentrate level influenced GPX activity and mRNA abundance of SOD2, XDH and poly (ADP-ribose) polymerase 1 (PARP1). Pluriparous animals exhibited higher serum GPX activities, a more distinct nadir for FRA and higher expression levels for GPX1, SOD2 and XDH. Primiparous cows displayed higher serum SOD activities. NA supplementation increased serum SOD activity antepartum in LC animals. Parturition was characterised by an increased need for antioxidants and an increased expression of oxidative stress-related genes that clearly differed with parity and was influenced by energy supply while NA exerted only minor effects on the investigated parameters.

Relationships between body temperatures and inflammation indicators under physiological and pathophysiological conditions in pigs exposed to systemic lipopolysaccharide and dietary deoxynivalenol.

We studied the constancy of the relationship between rectal and intraabdominal temperature as well as their linkage to inflammatory markers (leucocyte counts, kynurenine-to-tryptophan ratio (Kyn-Trp ratio), tumour necrosis factor alpha (TNF-α) in healthy and in pigs exposed to lipopolysaccharide (LPS) and/or deoxynivalenol (DON). Barrows (n = 44) were fed 4 weeks either a DON-contaminated (4.59 mg DON/kg feed) or a control (CON) diet and equipped with an intraabdominal temperature logger and a multicatheter system (V.portae hepatis, V.lienalis, Vv.jugulares) facilitating infusion of 0.9% NaCl (CON) or LPS (7.5 µg/kg BW) and simultaneous blood sampling. Body temperatures were measured and blood samples taken every 15 min for leucocyte counts, TNF-α and Kyn-Trp ratio. Combination of diet and infusion created six groups: CON_CONjug .-CONpor. , CON_CONjug. -LPSpor. , CON_LPSjug. -CONpor. , DON_CONjug. -CONpor. , DON_CONjug. -LPSpor. , DON_LPSjug. -CONpor. . The relationship between both temperatures was not uniform for all conditions. Linear regression revealed that an intraabdominal increase per 1°C increase in rectal temperature was ~25% higher in all LPS-infused pigs compared to NaCl-infusion, albeit diet and site of LPS infusion modified the magnitude of this difference. Inflammatory markers were only strongly present under LPS influence and showed a significant relationship with body temperatures. For example, leucocyte counts in clinically inconspicuous animals were only significantly correlated to core temperature in DON-fed pigs, but in all LPS-infused groups, irrespective of diet and temperature method. In conclusion, the gradient between body core and rectal temperature is constant in clinically inconspicuous pigs, but not under various pathophysiological conditions. In the latter, measurement of inflammatory markers seems to be a useful completion.

Effects of body condition, monensin, and essential oils on ruminal lipopolysaccharide concentration, inflammatory markers, and endoplasmatic reticulum stress of transition dairy cows.

Evidence exists that dairy cows experience inflammatory-like phenomena in the transition period. Rumen health and alterations in metabolic processes and gene networks in the liver as the central metabolic organ might be key factors for cows' health and productivity in early lactation. This study made use of an animal model to generate experimental groups with different manifestations of postpartal fat mobilization and ketogenesis. In total, 60 German Holstein cows were allocated 6 wk antepartum to 3 high-body condition score (BCS) groups (BCS 3.95) and 1 low-BCS group (LC; BCS 2.77). High-BCS cows were fed an antepartal forage-to-concentrate ratio of 40:60 on dry matter basis, in contrast to 80:20 in the LC group, and received a monensin controlled-release capsule (HC/MO), a blend of essential oils (HC/EO), or formed a control group (HC). We evaluated serum haptoglobin, kynurenine, tryptophan, ruminal lipopolysaccharide concentration and mRNA abundance of nuclear factor kappa B (NF-κB), nuclear factor E2-related factor 2 (Nrf2), and endoplasmatic reticulum stress-induced unfolded protein response (UPR) target genes in liver biopsy samples from d -42 until +56 relative to calving. Nearly all parameters were highly dependent on time, with greatest variation near calving. The ruminal lipopolysaccharide concentration and evaluated target genes were not generally influenced by antepartal BCS and feeding management. The kynurenine-to-tryptophan ratio was higher in LC than in HC/MO treatment on d 7. Ruminal lipopolysaccharide concentration was higher in HC/MO than in the HC group, but not increased in HC/EO group. Abundance of UPR target gene X-box binding protein 1 was higher in HC/MO than in HC/EO group on d 7. Hepatic mRNA abundance of Nrf2 target gene glutathione peroxidase 3 was higher, whereas expression of NF-κB target gene haptoglobin tended to be higher in LC than in HC/EO cows. The HC/MO cows showed the most prominent increase in the abundance of glutathione peroxidase 3 and haptoglobin after calving in comparison to antepartal values. Results indicate the presence of inflammatory-like phenomena near calving. Simultaneously, alterations in UPR and Nrf2 target genes with antioxidative properties and haptoglobin occurred, being most prominent in LC and HC/MO group.

Influence of conjugated linoleic acid and vitamin E on performance, energy metabolism, and change of fat depot mass in transitional dairy cows.

The objective of this experiment was to determine the effects of conjugated linoleic acid (CLA) and vitamin E as well as their interaction on performance variables and lipomobilization during late pregnancy and early lactation (wk 6 antepartum until wk 10 postpartum). For this purpose, 59 pluriparous German Holstein cows were assigned to 4 dietary groups in a 2 × 2 design with the factors CLA and vitamin E at 2 levels. For this trial, we selected cows with a high body condition score because they are more likely to mobilize fat and consequently are at a higher risk of developing ketosis. Furthermore, concentrate proportions were adjusted to provoke ketosis. Lactation performance variables were analyzed in 3 periods (d 42 antepartum until calving, 1 to 21 d in milk, 22 to 70 d in milk). Dry matter intake and net energy intake were reduced in animals receiving CLA. Milk fat content was reduced in the CLA group compared with the control group (4.83 vs. 5.46% in period 2; 3.36 vs. 4.57% in period 3). In the vitamin E and the CLA + vitamin E groups, reduction of milk fat content was observed in period 3 (3.76 vs. 4.57% compared with the control group). Milk yield was not affected by treatment. ß-Hydroxybutyrate concentrations and liver lipid contents were not influenced by CLA or vitamin E. Moreover, longitudinal changes of adipose tissue depot mass were not affected by dietary treatments. Results suggest that the effects CLA had on milk composition were compensated by an increased milk yield and a decreased dry matter intake. Reduced milk energy output in CLA-treated animals was compensated by a reduced dry matter intake. Therefore, the net energy balance was not affected by either treatment. Consequently, we found no group effect on the mobilization of adipose tissue.

Effects of two commercial diets and technical feed treatment on stomach lesions and immune system of fattening pigs.

The impact of technical feed treatment and diet on stomach lesions and traits of the local and systemic immune system were investigated in fattening pigs. Feeding groups differed in technical feed treatment (standard ground meal vs. finely ground and pelleted feed) and diet (soya bean meal vs. rapeseed meal/DDGS/soya beans). Pigs were fattened approximately 10 weeks by ad libitum feeding and slaughtered subsequently. Gastric alterations were assessed by a macroscopic scoring system [macroscopic stomach score (MSC) 0 =  normal to 4 =  severe lesions]. For immunological investigations, lymphocytes from blood and jejunal tissues were isolated. T-cell phenotyping was carried out by staining intestinal lymphocytes with monoclonal antibodies for CD4 and CD8 and flow cytometric measurements. MSC was higher in animals fed finely ground and pelleted feed compared with their counterparts. Significant interactions between diet and feed treatment considering the MSC were observed (p = 0.027). There was no effect of diet or technical feed treatment on T cells of blood, Lymphonodi gastrici or lamina propria (LP) and intraepithelial cells. However, technical feed treatment significantly affected subsets of CD4+ , CD8+ , CD8low , CD4/CD8 double-positive T cells, the mean fluorescence intensity of CD4+ T cells and the ratio of CD8low /CD8high T cells in Peyer's patches (PP). All named parameters were reduced in PP of animals fed finely ground and pelleted feed compared with animals fed standard ground meal. Furthermore, significant differences between T cells of lymph nodes and LP were observed between animals with middle MSC (MSC = 1-2.5) and animals with high MSC (MSC = 3-4). Significant alterations in T cells of PP were observed between animals of low (MSC = 0-0.5) and high MSC. The observed effects provide the evidence that the impact of technical feed treatment is not limited on the stomach lesions. Possible stimuli and consequences of the immune system should be studied in more detail.

Effects of monensin and essential oils on immunological, haematological and biochemical parameters of cows during the transition period.

Using a model to generate experimental groups with different manifestations of post-partum (p.p.) fat mobilization and ketogenesis, the effects of a dietary and a medical intervention on biochemical and haematological parameters, antibody titre, leucocytes subsets and function of transition cows were examined. In total, 60 German Holstein cows were allocated 6 weeks antepartum (a.p.) to 3 high-body condition score (BCS) groups (BCS 3.95) and 1 low-BCS group (LC, BCS 2.77). High-BCS cows received a monensin controlled-release capsule (HC/MO) or a blend of essential oils (HC/EO) or formed a control group (HC). Parameters were evaluated in 3 periods (day (d) -42 until calving, 1 until 14 days in milk (DIM), 15 until 56 DIM). Over the course of trial, various parameters were influenced by period with greatest variability next to calving. White blood cell count was higher in the HC (8.42 × 103 /µl) and HC/EO (8.38 × 103 /µl) groups than in the HC/MO group (6.81 × 103 /µl) considering the whole trial. Supplementation of monensin decreased aspartate aminotransferase in comparison with the HC group similar to LC treatment. Bilirubin concentration was nearly doubled in all high-BCS cows in period 2. In period 3, essential oils increased γ-glutamyltransferase (80.4 Units/l) in comparison with all other groups and glutamine dehydrogenase (61 Units/l) in comparison with the LC (19 Units/l) and the HC/MO group (18 Units/l). Results suggest that parameters were generally characterized by a high variability around calving. Based on biochemical characteristics, it appeared that the HC cows seemed to have compromised hepatocyte integrity when compared to the LC cows. From the immune parameters investigated, the BVDV antibody response was more pronounced in HC/MO compared to HC/EO.

Haematological and febrile response to Escherichia coli lipopolysaccharide in 12-week-old cockerels of genetically diverse layer lines fed diets with increasing L-arginine levels.

Due to its decisive function in the avian metabolic, endocrine and immune system L-arginine (Arg) is dietary indispensable for chickens. In 12-week-old cockerels of two high- and two low-performing purebred layer lines, the effects of increasing dietary Arg on the haematological and febrile response were studied over 48 h after single lipopolysaccharide (LPS) injection. The offered diets contained Arg equivalent to 70%, 100% and 200% of recommended supply. Pathophysiological alterations in weight gain, feed intake, body temperature and differential blood count were examined in comparison with their physiological initial values. Within the first 24 h after LPS injection, cockerels reduced feed intake and lost body weight subsequently. Thereby, low-performing genotypes lost body weight to a lesser extent than high-performing ones. The loss of body weight was further intensified by deficient dietary Arg. Within the following 24 h, cockerels recovered by improving feed intake and weight gain. Furthermore, LPS induced genotype-specific fever response: both brown genotypes showed initial hypothermia followed by longer lasting moderate hyperthermia, whereas the white genotypes exhibited biphasic hyperthermia. Fever response was accompanied by significant changes in differential blood counts. Characterized by lymphopenia and heterophilia, a severe leucopenia was observed from 4 to 8 h after LPS injection and replaced by a marked leucocytosis with longer lasting monocytosis up to 48 h after LPS injection. Under given pathophysiological conditions, deficiently Arg-supplied cockerels showed higher total leucocyte counts than adequately and excessively Arg-supplied cockerels. However, deficient and surplus dietary Arg tended to cause higher ratios between heterophils and lymphocytes. To conclude, present results confirmed that LPS induced numerous immunological changes in 12-week-old cockerels and emphasized that chicken's genotype is a source of variation to be considered for immunological studies. Deficient dietary Arg intensified acute changes in differential blood counts and weight gain during LPS-induced inflammation.

Mitochondrial DNA copy number and biogenesis in different tissues of early- and late-lactating dairy cows.

Energy balance in dairy cows changes during the course of lactation due to alterations in voluntary feed intake and energy required for milk synthesis. To adapt to the demands of lactation, energy metabolism needs to be regulated and coordinated in key organs such as adipose tissue (AT), liver, and mammary gland. Mitochondria are the main sites of energy production in mammalian cells and their number varies depending on age, organ, and physiological condition. The copy number of the mitochondrial genome, the mitochondrial DNA (mtDNA), reflects the abundance of mitochondria within a cell and is regulated by transcriptional and translational factors. Environmental, physiological, and energetic conditions change during lactation and we thus hypothesized that these changes may influence the mtDNA copy number and the abundance of genes regulating mitochondrial biogenesis. Therefore, we aimed to provide an overview of mitochondrial biogenesis in liver, subcutaneous (sc)AT, mammary gland, and peripheral blood cells during early and late lactation in dairy cows. German Holstein cows (n=21) were fed according to their requirements, and biopsies from scAT, liver, mammary gland, and blood were collected in early and late lactation and assayed for relative mtDNA copy numbers and the mRNA abundance of genes regulating mitochondrial biogenesis, such as nuclear-respiratory factor 1 and 2 (NRF-1, NRF-2), mitochondrial transcription factor A (TFAM), and peroxisome proliferator-activated receptor-gamma coactivator 1-α (PGC-1α). The number of mtDNA copies increased from early to late lactation in all tissues, whereas that in peripheral blood cells was greater in early compared with late lactation. Moreover, mitochondrial activity enzymes (i.e., citrate synthase and cytochrome c oxidase) increased from early to late lactation in scAT. Comparing the number of mtDNA copies between tissues and blood in dairy cows, the highest mtDNA content was observed in liver. The mRNA abundance of genes related to mitochondrial biogenesis changed in a tissue-specific manner when comparing early versus late lactation. The mtDNA copy number was associated with transcriptional factors only in AT, suggesting nontranscriptional regulation of mtDNA in the other tissues. We detected strong correlations between peripheral blood mtDNA and tissue mtDNA content in early lactation. Peripheral blood forms an appropriate medium to display the cellular content of mtDNA copy numbers and consequently the cellular energy status of tissues during early lactation.

Short communication: Telomere lengths in different tissues of dairy cows during early and late lactation.

Telomeres create a protective cap on the ends of chromosomes that shorten with cell division and are influenced by stressful conditions. With the onset of lactation, high-yielding dairy cows are exposed to metabolic stress. In the present study, we aimed to analyze telomere length (TL) in key metabolic organs, such as liver, subcutaneous (sc) adipose tissue (AT), and mammary gland, as well as in peripheral blood cells during early and late lactation in German Holstein cows (n=21). Animals were fed according to their requirement, and biopsies from scAT, liver, and mammary gland as well as blood cells were collected in early and late lactation. The relative quantity of telomere products (qT), which is proportional to the average TL, was determined in genomic DNA by multiplex quantitative PCR. In this study, relative qT varied widely in the investigated tissues and blood. In late lactation, slowly proliferating tissues, such as liver and scAT, had the highest qT, whereas peripheral blood cells and in the mammary gland had the lowest qT. Comparing early with late lactation, relative qT attrition was limited to blood and mammary gland. Relationships between relative qT in blood, mammary gland, scAT, and liver suggest that blood qT might serve as a surrogate marker for tissue-specific qT. Cows with high initial qT in tissues and blood in early lactation had greater qT attrition during the course of lactation than cows with lower qT. The determination of qT could be included when phenotyping dairy cattle to test for associations with performance and fitness traits.

The effects of a ration change from a total mixed ration to pasture on health and production of dairy cows.

In pasture-based dairy production systems, dairy cows often receive a silage- and concentrate-based ration [total mixed ration (TMR)] during wintertime and are gradually introduced to fresh herbage in spring. The present study aimed to investigate how the transition to this new nutritional situation influenced different production and health indicators. A 10-wk trial was performed in spring 2014, including 60 dairy cows of the German Holstein breed (166±23 d in milk, 23.5±3.7 kg of milk/d; means ± SD). The cows were divided into a pasture and a confinement group (PG and CG, respectively). The CG stayed on a TMR-based diet (35% corn silage, 35% grass silage, 30% concentrate; DM basis), whereas the PG was gradually transitioned from a TMR- to a pasture-based ration (wk 1=TMR-only, wk 2=3 h/d on pasture, wk 3 and 4=12 h/d on pasture, wk 5-10=pasture-only). A continuous grazing system was implemented on a ryegrass dominated pasture and temperature humidity indices were assessed based on continuous recording of temperature and humidity indoors as well as outdoors. Dry matter intake (DMI) from TMR, milk production, body weight (BW), and body condition score decreased as soon as the PG had partial access to pasture. Milk production and BW decreased even further in the first week on a full grazing ration, but thereafter BW increased again and milk production stabilized. The DMI estimation using the n-alkane method in wk 7 and 9 revealed an increase in DMI from pasture between the 2 time points and indicates an adaptation of grazing behavior and metabolism over several weeks. Increased serum ß-hydroxybutyrate and fatty acids concentrations at several time points, as well as a continuous body condition score decrease during the whole course of the trial, indicate an energy deficit in the PG. A significant correlation between serum glucose concentrations and the temperature humidity indices was observed. An increase in serum and milk urea concentrations as well as an increase in the urine total N to creatinine ratio occurred in the PG. To assess possible negative effects of the ration change on metabolic and liver health, different clinical chemistry variables and complete blood counts were assessed. No biologically relevant changes were observed for serum albumin, total protein, cholesterol, aspartate transaminase, γ-glutamyltransferase, and glutamate dehydrogenase concentrations, as well as for white and red blood cell counts.

The effects of a ration change from a total mixed ration to pasture on rumen fermentation, volatile fatty acid absorption characteristics, and morphology of dairy cows.

To investigate the effect of the change from a concentrate and silage-based ration (total mixed ration, TMR) to a pasture-based ration, a 10-wk trial (wk 1-10) was performed, including 10 rumen- and duodenum-fistulated German Holstein dairy cows (182±24 d in milk, 23.5±3.5kg of milk/d; mean ± standard deviation). The cows were divided in either a pasture group (PG, n=5) or a confinement group (CG, n=5). The CG stayed on a TMR-based ration (35% corn silage, 35% grass silage, 30% concentrate; dry matter basis), whereas the PG was gradually transitioned from a TMR to a pasture-based ration (wk 1: TMR only; wk 2: 3 h/d on pasture wk 3 and 4: 12 h/d on pasture wk 5-10: pasture only). Ruminal pH, volatile fatty acids (VFA), NH3-N, and lipopolysaccharide (LPS) concentrations were measured in rumen fluid samples collected medially and ventrally on a weekly basis. Ruminal pH was continuously recorded during 1 to 4 consecutive days each week using ruminal pH measuring devices. In wk 1, 5, and 10, rumen contents were evacuated and weighed, papillae were collected from 3 locations in the rumen, and subsequently a VFA absorption test was performed. In the PG, mean rumen pH and molar acetate proportions decreased, and molar butyrate proportions increased continuously over the course of the trial, which can most likely be ascribed to an increased intake of rapidly fermentable carbohydrates. During the first weeks on a full grazing ration (wk 5-7), variation of rumen pH decreased, and in wk 5 a lower rumen content, papillae surface area, and potential for VFA absorption were observed. In wk 8 to 10, variation of rumen pH and total VFA concentrations increased again, and acetate/propionate ratio decreased. In wk-10 rumen content, papillae area and VFA absorption characteristics similar to initial levels were observed. Although continuous rumen pH assessments and LPS concentrations did not reveal an increased risk for subacute rumen acidosis (SARA) during the adaption period, histopathology of rumen papillae and potential for VFA absorption indicated a possible risk for rumen health. An increased risk for SARA was observed in wk 9 and 10 in the PG, but rumen LPS concentrations and histopathology were not adversely affected. Results of the present study suggest that after behavioral and metabolic adaptation to the transition from a TMR to a pasture-based ration, no adverse effects on rumen morphology and absorption capacity occurred, although rumen pH after adaptation to pasture indicated increased risk of SARA.

Metabolic and clinical response to Escherichia coli lipopolysaccharide in layer pullets of different genetic backgrounds supplied with graded dietary L-arginine.

L-arginine (Arg) is an essential amino acid in birds that plays a decisive role in avian protein synthesis and immune response. Effects of graded dietary Arg supply on metabolic and clinical response to Escherichia coli lipopolysaccharide (LPS) were studied over 48 hours after a single intramuscular LPS injection in 18-week-old genetically diverse purebred pullets. LPS induced a genotype-specific fever response within 4 hours post injectionem. Whereas brown genotypes showed an initial hypothermia followed by longer-lasting moderate hyperthermia, white genotypes exhibited a biphasic hyperthermia without initial hypothermia. Furthermore, within 2 hours after LPS injection, sickness behavior characterized by lethargy, anorexia, intensified respiration, and ruffled feathers appeared, persisted for 3 to 5 hours and recovered 12 hours post injectionem. The varying grades of Arg did not alter the examined traits named above, whereas insufficient Arg reduced body growth and increased relative weights of liver and pancreas significantly. At 48 hours post injectionem, increased relative weights of liver and spleen were also found in LPS treated pullets, whereas LPS decreased those of pancreas, bursa, thymus, and cecal tonsils. Moreover, LPS lowered the sum of plasma amino acids and decreased plasma concentrations of Arg, citrulline, glutamate, methionine, ornithine, phenylalanine, proline, tryptophan, and tyrosine, and increased those of aspartate, glutamine, lysine, 1- and 3-methyl-histidine. Elevating concentrations of dietary Arg led to increasing plasma concentrations of Arg, citrulline, ornithine, and 3-methyl-histidine subsequently. As quantitative expression of LPS-induced anorexia, proteolysis, and the following changes in plasma amino acids, pullets showed a significant decrease of feed and nitrogen intake and catabolic metabolism characterized by negative nitrogen balance and body weight loss in the first 24 hours post injectionem. Pullets recovered from the challenge within the second 24 hours post injectionem and changed to anabolism with re-increased feed and nitrogen intake, positive nitrogen retention, and weight gain. To conclude, present results confirmed that LPS induced numerous metabolic and physiological changes in pullet's genotypes, whereas dietary Arg affected the examined traits only slightly.

Effect of monensin and essential oils on performance and energy metabolism of transition dairy cows.

This work examined preventive effects of a dietary and a medical intervention measure on postpartum (p.p.) ketogenesis in dairy cows overconditioned in late pregnancy. Sixty German Holstein cows were allocated 6 weeks antepartum (a.p.) to three high body condition score (BCS) groups (BCS 3.95 ± 0.08) and one low BCS group (LC, BCS 2.77 ± 0.14). Concentrate proportion in diet a.p. was higher (60% vs. 20%) and increase in proportion p.p. from 30% up to 50% decelerated (3 vs. 2 weeks) in high BCS groups. High BCS cows received a monensin controlled-release capsule (CRC) (HC/MO), a blend of essential oils (HC/EO) or formed a control group (HC). Performance parameters and energy status were evaluated in three periods [day (d) -42 until calving, one until 14 days in milk (DIM), 15 until 56 DIM]. Feed efficiency was 65% and 53% higher in HC/MO than in LC (p < 0.001) and HC groups (p = 0.002) in the second period. Milk fat content was higher in HC/EO (5.60 vs. 4.82%; p = 0.012) and milk urea higher in HC/MO (135 mg/kg) than in LC cows (107 mg/kg; p < 0.001). Increased p.p. levels of non-esterified fatty acids in serum were found in HC (p = 0.003), HC/MO (p = 0.068) and HC/EO (p = 0.002) in comparison with LC cows. Prevalence of subclinical and clinical ketosis was 54% and 46%, respectively, in HC group. Monensin decreased the prevalence to 50% and 7% respectively. Ruminal fermentation pattern showed higher proportions of propionate (23.43 mol % and 17.75 mol %, respectively; p < 0.008) and lower acetate:propionate ratio (2.66 vs. 3.76; p < 0.001) in HC/MO than HC group. Results suggest that a monensin CRC improved energy status and feed efficiency of transition dairy cows while essential oils failed to elicit any effect.

Real-time phase-contrast flow MRI of haemodynamic changes in the ascending aorta and superior vena cava during Mueller manoeuvre.

AIM: To evaluate the potential of real-time phase-contrast flow magnetic resonance imaging (MRI) at 40 ms resolution for the simultaneous determination of blood flow in the ascending aorta (AA) and superior vena cava (SVC) in response to reduced intrathoracic pressure (Mueller manoeuvre). MATERIALS AND METHODS: Through-plane flow was assessed in 20 healthy young subjects using real-time phase-contrast MRI based on highly undersampled radial fast low-angle shot (FLASH) with image reconstruction by regularized non-linear inversion. Haemodynamic alterations (three repetitions per subject = 60 events) were evaluated during normal breathing (10 s), inhalation with nearly closed epiglottis (10 s), and recovery (20 s). RESULTS: Relative to normal breathing and despite interindividual differences, reduced intrathoracic pressure by at least 30 mmHg significantly decreased the initial peak mean velocity (averaged across the lumen) in the AA by -24 ± 9% and increased the velocity in the SVC by +28 ± 25% (p < 0.0001, n = 23 successful events). Respective changes in flow volume per heartbeat were -25 ± 9% in the AA and +49 ± 44% in the SVC (p < 0.0001, n = 23). Flow parameters returned to baseline during sustained pressure reduction, while the heart rate was elevated by 10% (p < 0.0001) after the start (n = 24) and end (n = 17) of the manoeuvre. CONCLUSIONS: Real-time flow MRI during low intrathoracic pressure non-invasively revealed quantitative haemodynamic adjustments in both the AA and SVC.

Glioma infiltration of the corpus callosum: early signs detected by DTI.

The most frequent primary brain tumors, anaplastic astrocytomas (AA) and glioblastomas (GBM): tend to invasion of the surrounding brain. Histopathological studies found malignant cells in macroscopically unsuspicious brain parenchyma remote from the primary tumor, even affecting the contralateral hemisphere. In early stages, diffuse interneural infiltration with changes of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) is suspected. The purpose of this study was to investigate the value of DTI as a possible instrument of depicting evidence of tumor invasion into the corpus callosum (CC). Preoperatively, 31 patients with high-grade brain tumors (8 AA and 23 GBM) were examined by MRI at 3 T, applying a high-resolution diffusion tensor imaging (DTI) sequence. ADC- and FA-values were analyzed in the tumor-associated area of the CC as identified by fiber tracking, and were compared to matched healthy controls. In (MR-)morphologically normal appearing CC the ADC values were elevated in the tumor patients (n = 22; 0.978 × 10(-3) mm²/s) compared to matched controls (0.917 × 10(-3) mm²/s, p < 0.05), and the corresponding relative FA was reduced (rFA: 88 %, p < 0.01). The effect was pronounced in case of affection of the CC visible on MRI (n = 9; 0.978 × 10(-3) mm²/s, p < 0.05; rFA: 72 %, p < 0.01). Changes in diffusivity and anisotropy in the CC can be interpreted as an indicator of tumor spread into the contralateral hemisphere not visible on conventional MRI.

Phylogenetic analyses of morphological evolution in the gametophyte and sporophyte generations of the moss order Hookeriales (Bryopsida).

Morphological characters from the gametophyte and sporophyte generations have been used in land plants to infer relationships and construct classifications, but sporophytes provide the vast majority of data for the systematics of vascular plants. In bryophytes both generations are well developed and characters from both are commonly used to classify these organisms. However, because morphological traits of gametophytes and sporophytes can have different genetic bases and experience different selective pressures, taxonomic emphasis on one generation or the other may yield incongruent classifications. The moss order Hookeriales has a controversial taxonomic history because previous classifications have focused almost exclusively on either gametophytes or sporophytes. The Hookeriales provide a model for comparing morphological evolution in gametophytes and sporophytes, and its impact on alternative classification systems. In this study we reconstruct relationships among mosses that are or have been included in the Hookeriales based on sequences from five gene regions, and reconstruct morphological evolution of six sporophyte and gametophyte traits that have been used to differentiate families and genera. We found that the Hookeriales, as currently circumscribed, are monophyletic and that both sporophyte and gametophyte characters are labile. We documented parallel changes and reversals in traits from both generations. This study addresses the general issue of morphological reversals to ancestral states, and resolves novel relationships in the Hookeriales.