Publications by authors named "Manfred Mielenz"

Phosphorous (P) resources are finite. Sewage sludge recyclates (SSR) are not only of interest as plant fertilizer but also as potential source of minerals in animal nutrition. However, besides P and calcium (Ca), SSR contain heavy metals.

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In recent years, interest in the larvae of black soldier fly (BSF) (Hermetia illucens) as a sustainable protein resource for livestock feed has increased considerably. However, knowledge on the nutritional and physiological aspects of this insect, especially compared to other conventional farmed animals is scarce. This review presents a critical comparison of data on the growth potential and efficiency of the BSF larvae (BSFL) compared to conventional monogastric livestock species.

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Mastitis has a high incidence in dairy cows. Experimental infection with Escherichia coli increased the number of leukocytes in milk and the gene expression of the chemokine receptor CXCR4 in mammary gland tissues. A link between CXCR4 expression and lipopolysaccharide sensing was demonstrated in other species using in vitro models.

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Prebiotic supplements and high-protein (HP) diets reduce body weight and modulate intestinal microbiota. Our aim was to elucidate the combined effect of an inulin/oligofructose (FOS) and HP diet on body weight gain, energy metabolism and faecal microbiota. Forty male C57BL/6NCrl mice were fed a control (C) diet for 2 weeks and allocated to a C or HP (40 % protein) diet including no or 10 % inulin/FOS (C + I and HP + I) for 4 weeks.

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Diets of dairy cows are often based on maize silage (MS), delivering lower amounts of n-3 fatty acids (FA) compared to grass silage-based diets. The fatty acid composition of the cell membrane can affect the cell function. We evaluated the effects of an MS-based diet on bovine red blood cell (RBC) membrane FA composition and dietary effects on controlled ATP release of RBC.

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The regulation of growth hormone (GH) release during prenatal development and during early postnatal life is not entirely clarified. In this study plasma GH concentrations in pigs with inherited pseudo vitamin D deficiency type I (PDDR-I), which regularly show growth retardation, were compared during ontogeny with unaffected pigs of the same breed (German Landrace, DL) as control. Plasma GH concentrations were measured in plasma of chronically catheterized fetuses (beginning on day 101 after mating or after artificial insemination) and in piglets (day 37 postpartum (p.

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The pre-weaning period is critical for calf health and growth, and intensive milk feeding programs may assist postnatal development by improving body growth and organ maturation. The aim of the present work was to study the effects of ad libitum milk replacer (MR) feeding on the growth, metabolic adaptation, health, and immune status of newborn calves. Twenty-eight newborn Holstein and Holstein x Charolais crossbred calves were fed ad libitum (ADLIB) or in restricted amounts (6 liters per day; RES) during the first five weeks of life.

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It is well observed that feeding energy-dense diets in dairy cows during the dry period can cause metabolic imbalances after parturition. Especially dairy cows with high body condition score (BCS) and fed an energy-dense diet were prone to develop production diseases due to metabolic disturbances postpartum. An experiment was conducted to determine the effects of an energy-dense diet and nicotinic acid (NA) on production and metabolic variables of primiparous and multiparous cows in late pregnancy and early lactation which were not pre-selected for high BCS.

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High ambient temperatures have severe adverse effects on biological functions of high-yielding dairy cows. The metabolic adaption to heat stress was examined in 14 German Holsteins transition cows assigned to two groups, one heat-stressed (HS) and one pair-fed (PF) at the level of HS. After 6 days of thermoneutrality and ad libitum feeding (P1), cows were challenged for 6 days (P2) by heat stress (temperature humidity index (THI) = 76) or thermoneutral pair-feeding in climatic chambers 3 weeks ante partum and again 3 weeks post-partum.

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Adipose tissue is an endocrine compartment that plays an important role in immune defence by producing and releasing a wide range of proteins, including acute phase proteins (APPs). The liver is the main organ of APP synthesis, although extrahepatic production has also been reported. In the present study, expression of two APPs in dairy cattle, lipopolysaccharide binding protein (LBP) and α1-acid glycoprotein (AGP), was determined in four visceral (pericardial, mesenteric, omental and retroperitoneal) and three subcutaneous (withers, tail head and sternum) adipose tissue depots.

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The transition period in dairy cows (3 weeks prepartum until 3 weeks postpartum) is associated with substantial mobilization of energy stores, which is often associated with metabolic diseases. Nicotinic acid (NA) is an antilipolytic and lipid-lowering compound used to treat dyslipidaemia in humans, and it also reduces non-esterified fatty acids in cattle. In mice the G-protein coupled receptor 109A (GPR109A) ligand NA positively affects the secretion of adiponectin, an important modulator of glucose and fat metabolism.

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Adiponectin and intracellular 5'adenosine monophosphate-activated protein kinase (AMPK) are important modulators of glucose and fat metabolism. Cinnamon exerts beneficial effects by improving insulin sensitivity and blood lipids, e.g.

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In dairy cows the milk associated energy output in early lactation exceeds the input via voluntary feed intake. To spare glucose for mammary lactose synthesis, peripheral insulin sensitivity (IS) is reduced and fat mobilization is stimulated. For these processes a link between IS and the endocrine functions of adipose tissue (AT) is likely; we thus aimed to characterise the mRNA expression from bovine AT derived proteins and receptors that are related to IS according to the literature in metabolically active tissues plus systemic IS throughout lactation.

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Decreasing insulin sensitivity (IS) in peripheral tissues allows for partitioning nutrients towards the mammary gland. In dairy cows, extensive lipid mobilization and continued insulin resistance (IR) are typical for early lactation. Adiponectin, an adipokine, promotes IS.

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Adiponectin (AdipoQ) is an adipokine mainly secreted by white fatty tissue, playing a major role in energy homeostasis and insulin sensitivity. For cattle, AdipoQ data are largely limited to mRNA expression; to our knowledge, valid information about the AdipoQ protein in bovine tissues and body fluids is not available. Therefore, we have developed a monoclonal antibody against bovine AdipoQ.

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The acute phase protein haptoglobin (Hp) exerts immune modulating functions in the innate and adaptive immune system. In pigs, serum Hp concentrations are linked to impaired growth performance. There is little information on Hp in newborn piglets and the onset of endogenous Hp synthesis.

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The present study was aimed to determine the association between metalloproteinase 3 (MMP3), transforming growth factor beta 1 (TGFβ1) and collagen type X alpha I (COL10A1) gene polymorphisms with traits related to leg weakness in pigs. Three hundred Duroc × Pietrain cross breds (DuPi) and 299 pigs of a commercial population (CP) were used for the experiment. DuPi animals were examined for 10 different traits describing leg and feet structure, osteochondrosis (OC) scores and bone density status.

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Background: Leg weakness issues are a great concern for the pig breeding industry, especially with regard to animal welfare. Traits associated with leg weakness are partly influenced by the genetic background of the animals but the genetic basis of these traits is not yet fully understood. The aim of this study was to identify quantitative trait loci (QTL) affecting leg weakness in pigs.

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Among dietary components, conjugated linoleic acids (CLAs) have attracted considerable attention as weight loss supplements in the Western world because they reduce fat stores and increase muscle mass. However, a number of adverse effects are also ascribed to the intake of CLAs such as aggravation of insulin resistance and the risk of developing diabetes. However, the mechanisms accounting for the effects of CLAs on glucose homeostasis are incompletely understood.

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Osteochondrosis (OC) or leg weakness is an economically important disease of young fast growing pigs and is a concern of animal welfare. The etiology and pathogenesis of osteochondrosis is not fully understood yet, but any abnormalities in the formation of hypertrophic chondrocytes and disrupted blood supply to the growth cartilage are very important predisposing factors. Matrix gla protein (MGP) as a potential calcification inhibitor of extracellular matrix might contribute to the development of OC.

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Adipose tissue expresses adipokines, which are involved in regulation of energy expenditure, lipid metabolism, and insulin sensitivity. To adapt for the transition from pregnancy to lactation, particularly in high-yielding dairy cows, adipokines, their receptors, and particular G-protein coupled receptors (GPRs) are of potential importance. Signaling by GPR 41 stimulates leptin release via activation by short-chain fatty acids; GPR 43/109A inhibits lipolysis, and GPR 109A thereby mediates the lipid-lowering effects of nicotinic acid and beta-hydroxybutyrate.

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Leptin is a key mediator of signals regulating food intake and energy expenditure and exerts potent immunomodulatory effects. We investigated the mechanisms mediating the action of leptin on GH secretion from peripheral blood mononuclear cells (PBMCs). Using immunofluorescence microscopy, we demonstrated a polarized expression pattern of leptin receptor protein on the surface of mononuclear cells and constitutive expression of GH in PBMCs.

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Enzymes of the Polo-like kinase (Plk) family are active in the pathways controlling mitosis in several species. We have cloned cDNA fragments of the porcine homologues of Plk1, Plk2, and Plk3 employing fetal fibroblasts as source. All three partial cDNAs showed high sequence homology with their mouse and human counterparts and contained the Polo box, a domain characteristic for all Polo kinases.

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