An effect of mammary gland infection caused by Streptococcus uberis on composition and physicochemical changes of cows' milk.

An effect of mammary gland infection caused by Streptococcus uberis on the changes in cows' milk composition and its physicochemical properties was examined. The study was conducted in the herd of Slovak Pied breed cattle (with a share of HF blood), in 2nd and 3rd lactation, after 4th month of milking. Milk samples were collected from a quarter milking. The samples were subjected to microbiological analysis, basic milk composition, total bacteria count, somatic cell count and physicochemical properties were examined. Also analyses of protein fractions share and fatty acids profile were conducted. An effect of bacterial infection of the mammary gland bring an increase (P<0.01) in somatic cell count was observed in this study. Milk samples contaminated with S. uberis were characterized by higher (P<0.05) total bacteria count and total protein compared to milk samples collected from non-infected mammary gland. The level of κ-casein was significantly (P<0.05) decreased in cows with subclinical mastitis caused by S. uberis. Significant (P<0.05) reduction in the share of C13:0 acid, and an increased level of C18:0, C18:1n7t and CLA were observed in milk contaminated with S. uberis compared to healthy cows' milk. It should be concluded that S. uberis causes the increase in total bacteria count, SCC and the decrease in κ-casein level, which significantly affects deterioration of technological quality of cows' milk.

Effects of udder infections with Staphylococcus xylosus and Staphylococcus warneri on the composition and physicochemical changes in cows milk.

The aim of this study was an evaluation of the effects of two species of coagulase negative staphylococci (CNS), Staphylococcus xylosus and Staphylococcus warneri, on the changes in technological parameters of cows' milk. The study was conducted in a herd of Slovak Pied cattle breed (with share of HF blood). Based on the performance results from three subsequent months, cows in the 2nd and 3rd lactation with SCC up to 200 thousand/ml (8 heads, 32 quarters), and above 800 thousand/ml (8 heads, 32 quarters), after the 4th month of lactation, were selected. The samples were subjected to microbiological analysis, total bacteria count, somatic cell count; basic milk composition and physicochemical properties were also examined. The research has found the impact of bacterial infection on the increasing (p<0.05) of the number of somatic cells and a decrease (p<0.01) in protein levels in milk due to both types of staphylococci. There was a significant (p<0.05) reduction in C8: 0, C10: 0 and the total amount of saturated fatty acids in the milk of the infected cows in comparison to the healthy ones. The research also revealed higher (p<0.01) levels of C14: 0 and C20: 1 in milk from the healthy cows.

In vitro study of the effect of corn dried distillers grains with solubles on rumen fermentation in sheep.

The aim of the in vitro study was to determine the effect of corn dried distillers grains with solubles (corn DDGS), used as a replacement for the concentrate ingredients of sheep diet, on rumen fermentation. The material for the study was the ruminal fluid of Polish Merino sheep which was incubated during 4-, 8- or 24-hour periods. Five groups of samples were prepared for in vitro fermentation: C - control, incubated with the substrate consisting of the concentrate ingredients; D1, D2 and D3, where DDGS was used as a substrate added in proportions of 10, 20 and 30% of dry matter of the concentrate; and D4, where 100% DDGS was used as a substrate. After fermentation, the gas and short chain fatty acids (SCFAs) analyses were performed using gas chromatography. The ammonia concentration and pH were also determined, and the SCFA utilization index (NGR), the fermentation efficiency (FE) and the index of cell yield of ruminal microorganisms (CY) were calculated. This research showed no effect of DDGS on the methane emission. The positive correlations between the amount of methane and ammonia concentrations in the 8- and 24-hour fermentation periods were found. DDGS addition increased propionate proportion, but decreased production of acetate (p<0.01). Additionally, D1, D2, D3 and D4 substrates lowered isobutyrate (p<0.05) and isovalerate (p<0.01) production. Based on the results obtained, it can be stated that partial substitution of the concentrate ingredients with DDGS did not have deleterious effect on sheep rumen fermentation processes.

Zitterbewegung of electrons in carbon nanotubes created by laser pulses.

We describe a possibility of creating non-stationary electron wave packets in zigzag carbon nanotubes (CNT) illuminated by short laser pulses. After the disappearance of the pulse the packet experiences a trembling motion (Zitterbewegung, ZB). The band structure of CNT is calculated using the tight-binding approximation generalized for the presence of radiation. By employing realistic pulse and CNT parameters we obtain the ZB oscillations with interband frequencies corresponding to specific pairs of energy bands. A choice of optimal parameters is presented in order to observe the phenomenon of ZB experimentally. The use of Gaussian wave packets to trigger the electron Zitterbewegung, as used in the literature, is critically reexamined.

The effects of aneurysm repair using an aortic prosthesis on the electrical parameters of the muscular layer of the abdominal aorta.

The study was carried out on 10 swine of 20-30 kg body weight. Five animals were assigned to each of 2 groups. An aneurysm of the abdominal aorta was created experimentally in animals from the first and second study group. After 4 weeks, animals from the second group were subject to aneurysm repair using an aortic prosthesis. During the experiment, we measured the myoelectric activity of the muscular layer of the abdominal aorta and aneurysmal lesion with the ultrasonographic technique. Measurements of the aorta and aneurysmal lesion and histopathological analyses were carried out post-mortem. We found a statistically significant decrease in the myoelectric activity of the aorta on the aorta-straight prosthesis interface and a significant decrease in the thickness of the muscular layer of the aorta on the aorta-prosthesis interface. No similar changes were found for experimentally induced aneurysms of the abdominal aorta. A straight prosthesis graft may not be the perfect option in the treatment of abdominal aortic aneurysm, as it contributes to the remodelling of the tissue on the prosthesis-aorta interface. This may result in the relapse of an aneurysm and post-operative complications.

Experimental methods of abdominal aortic aneurysm creation in swine as a large animal model.

Animal models of abdominal aortic aneurysms (AAA) enable preclinical studies on new therapeutic approaches and help to understand pathophysiology of the disease. The aim of this study was to demonstrate the effectiveness of selected methods of experimental induction of abdominal aortic aneurysm in swine and to adapt the EMG examination (electromyography) to record the vessel wall changes. The animals were divided into 3 groups comprising 4 individuals in whom AAA was surgically induced. In the first group the AAA was induced by mechanical stretching of the aortic wall and injection of 500 IU elastase under pressure. The second group received elastase and 6000 IU of collagenase. In the third group 0.5 M CaCl2 solution was introduced additionally. Enlargement of abdominal aorta was monitored for 4 weeks. The first group did not show any aorta dilatation. In the second group the aortic lumen was dilated on average by 71±3.5% (P≤0.001) as shown at autopsy and by 76.6±9.3% as measured by the ultrasound method. In the third group aorta was dilatated by 104.2±11.3% as obtained by ultrasound and 72±3% at post-mortem examination. Myoelectric activity of VSMC (vascular smooth muscle cell) was demonstrated and it was characterized by the presence of three types of waves closely related to the pressure changes in the vessel lumen. We conclude that collagen fibers damage plays a significant role in the AAA development in swine. The inflammatory process in the vessel's wall also contributes to AAA development. However, myoelectrical activity of VSMC does not significantly change despite histologically confirmed loss of muscular layer.

The effect of humic-fatty acid preparation on selected haematological and biochemical serum parameters of growing rabbits.

In this study, we assessed the effect of a humic-fatty acid preparation (HFA) used in rabbit feed on certain haematological and biochemical serum parameters (the lipid profile and the Ca, P and Fe contents). A higher RBC, HGB and HCT values were observed in the groups that were given HFA. An increase in Fe concentrations were also noted. The total and LDL cholesterol were lower in the groups which received HFA than in the control group.

In vitro study on the effects of some selected agonists and antagonists of alpha(1)-adrenergic receptors on the contractility of the aneurysmally-changed aortic smooth muscle in humans.

The study included 18 sections of the aneurysmally-changed abdominal aortas, obtained from patients of the Provincial Specialist Hospital in Wroclaw and 18 sections of normal abdominal aortas obtained from swine. The collected samples were placed horizontally in the incubation chamber. Changes in their transverse section area were registered. They were stretched to a tension of 5 mN. Krebs-Henseleit buffer was used as the incubatory environment. Incubation of the sections was performed at a temperature of 37°C, in the gaseous mixture of oxygen and carbon dioxide used in the following proportion: 95% of O(2) and 5% of CO(2). Contractions of the aorta were registered with isotonic transducers (Letica Scientific Instruments). In the studies, we examined the influence of α(1)-adrenergic receptors (and their subtypes α(1A), α(1B), α(1D)) on the contractility of the aortic muscle in humans and swine by their stimulation or inhibition with some selected agonists or antagonists. This time, it was shown that the stimulation of α(1)-adrenergic receptors leads to contractions of the human and swine aortic muscle; the observed increase in the muscle tone may follow from the stimulation of all subtypes of alpha-1 receptor (α(1A), α(1B), α(1D)). All three subtypes of 1-adrenergic receptor are engaged in vasoconstriction, especially of α(1A) and α(1D) subtypes; the α(1B) subtype is less significant for aortic contractility. The contractile response of the aneurysmally-changed abdominal aorta in humans to agonists of α-adrenergic receptors was significantly less intense than that of the normal porcine aorta. It can be concluded that aneurysms influence the contractile response of the aorta.

Trichinella spiralis: the influence of short chain fatty acids on the proliferation of lymphocytes, the goblet cell count and apoptosis in the mouse intestine.

This study was carried out to determine the influence of short chain fatty acids (SCFA) on spleen and mesenteric lymph node lymphocyte proliferation, goblet cells and apoptosis in the mouse small intestine during invasion by Trichinella spiralis. BALB/c mice were infected with 250 larvae of T. spiralis. An SCFA water solution containing acetic, propionic and butyric acids (30:15:20 mM) was administered orally starting 5 days before infection and ending 20 days post infection (dpi). Fragments of the jejunum were collected by dissection 7 and 10 dpi, and were examined for apoptotic cells in the lamina propria of the intestinal mucosa, and for goblet cells. The proliferation index of the cultured spleen and mesenteric lymph node lymphocytes with MTT test was also determined. The orally administered SCFA solution decreased the proliferation of mesenteric lymph node lymphocytes in the mice infected with T. spiralis at both examination times, but did not influence the proliferative activity of the spleen cells. Seven dpi, both in the spleen and mesenteric lymph nodes, the highest proliferation index of concanavalin A (Con A)-stimulated lymphocytes was found in the group of uninfected animals receiving SCFA animals. This tendency could still be seen 10 dpi in the mesenteric lymph nodes but not in the spleen, where the proliferation index in this group had significantly decreased. In vitro studies revealed, that butyric and propionic acids added to the cell cultures suppressed the proliferation of Con A-stimulated mesenteric lymph nodes and spleen lymphocytes taken from uninfected and T. spiralis-infected mice. Acetic acid stimulated proliferation of splenocytes taken from uninfected mice but did not affect lymphocyte proliferation in mesenteric lymph nodes from uninfected or infected mice. Orally administered SCFA increased the number of goblet cells found in the epithelium of the jejunum 7 dpi, but this number had decreased 10 dpi. The number of apoptotic cells in the lamina propria of the intestinal mucosa of animals infected with the T. spiralis and receiving SCFA was also lower, particularly 10 dpi. The above results show that SCFA can participate in the immune response during the course of trichinellosis in mice.

The effect of Linola and W92/72 transgenic flax seeds on the rabbit caecal fermentation--in vitro study.

The effect of W92/72 transgenic flax seeds taken from a variety of Linola on the production of SCFA, ammonia and methane by bacteria inhabiting rabbit caecum was studied. The in vitro method was used where caecal contents from rabbits was incubated with W92/72 transgenic or Linola flax seeds, or without any additives (control samples). The total concentration of SCFA was higher in samples with the addition of flax seeds than in the control samples. The increase in concentrations of acetic, propionic and butyric acids was the highest in samples with Linola seeds added. A higher percentage of propionic and butyric acids was observed in the contents incubated with addition of flax seeds as compared to the control samples. This increase was the result of a percentage decrease in acetic acid. No differences were observed in the concentration of ammonia between fermented samples. Moreover, the addition of flax seeds resulted in slight decrease of pH in incubated samples. In gas samples, the methane level was higher in samples with flax seeds added, although the highest level was found in samples with transgenic seeds. In addition, gas pressure was significantly higher in samples with flax seeds added as compared to control samples, and this may indicate a higher intensity of microbiological fermentation processes. These studies suggest that neither Linola nor W92/72 flax seeds have any unfavorable effect on the caecal microflora activity of rabbits. A beneficial influence of flax seeds on the microbiological fermentation process in rabbit caecum was observed, based on an increase in percentage ratio of propionic acid in samples with flax seeds added.

Effects of a skullcap root supplement on haematology, serum parameters and antioxidant enzymes in rabbits on a high-cholesterol diet.

We studied the effects of Scutellaria baicalensis root on blood parameters and antioxidant enzyme activities in rabbits fed a high-cholesterol diet. Thirty-two New Zealand White rabbits were divided into four groups of eight animals each. They were fed a standard diet (C group), a diet with a 1% pure cholesterol supplement (CH group), a diet with a 1% pure cholesterol supplement and a 9% skullcap root supplement (CH+SR group), or a diet with a 9% skullcap root supplement (SR group). After 6 weeks, the rabbits fed the high-cholesterol diet had significantly decreased RBC and Hb levels and significantly increased MCV, MCH and Fe levels (p≤ 0.05). The skullcap root supplement had no adverse effects on the haematological parameters. The values for RBC, Hb, HCT, MCV, MCH and MCHC were similar in the skullcap root-treated and control rabbits. We also observed a remarkable elevation in the serum TC, LDL and TG levels at the end of the 6-week period. The rabbits fed the cholesterol diet showed decreased activity of the erythrocyte GSH-Px compared with the rabbits fed the basal diet. The GSH-Px activity was significantly higher in the rabbits fed the CH+SR diet than in those on the CH diet. The erythrocyte SOD activity was also significantly decreased in the rabbits on the CH diet. However, the CH+SR group rabbits showed significantly enhanced erythrocyte SOD activity. The SOD level in the CH+SR rabbits was 34.91 U/ml, which was a 23% increase (p≤ 0.05) in relation to the results for the CH group and only 15% diminished in relation to the control group. These results suggest that the dietary supplementation of skullcap root may improve rabbit antioxidant systems and protect against the risks from a high-cholesterol diet.

Changes in selected serum parameters of broiler chicken fed supplemental chromium.

The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 microg/kg Cr. The supplementation of 500 mug/kg Cr increased body weight, weight gain and feed efficiency (p < 0.05). In addition, supplementation with Cr decreased the serum total cholesterol, LDL cholesterol (p < 0.05), triglycerides (p < 0.05) and glucose (p < 0.05) concentrations whereas serum HDL cholesterol increased. Serum total protein and serum Cr concentration slightly but not significantly increased in both Cr groups. The study suggest that Cr supplementation particularly at 500 microg/kg Cr from Cr yeast can influence on carbohydrate and lipid metabolism of broiler chicken and can be used as additives in animal diet but it still needs more investigations.

[The course of acute hepatic porphyria]. / Przebieg ostrych porfirii watrobowych.

Acute hepatic porphyrias are the diseases dependent on the congenital metabolic defects of the hem biosynthesis. The diagnosis of porphyria only on the grounds of clinical picture is extremely difficult as it is presented by the variety of symptoms, often imitating other diseases. In each case the diagnosis must be confirmed by the biochemical and enzymatic investigations. In the paper we described different clinical courses of the acute hepatic porphyrias. The acquaintance with the symptoms of porphyrias enables to decrease the number of complications connected with diagnostic and therapeutic errors what is still a serious economic problem.

Changes of energetic value and protein level of rumen content in sheep fed with stuff with livex and blood meal supplementation.

The aim of studies was to determine the influence of Wroclaw product from blood--brown, dried livex (modified by whey) and blood meal, which were added to sheep forage, on energetic value and protein, also volatile fatty acids (VFA) levels in rumen content of these animals. The samples of rumen content for determination of the three parameters mentioned above were taken 2.5 hrs after finished morning feeding. The addition of livex and blood meal to forage was 2%. When two non-conventional diet supplements were used in vivo, there was observed significant inhibitory influence of livex on methane level among rumen gases, amounting to 38.9% in sheep and increase in protein amount of about 25.92% (for blood meal these values were: 5.6% and 7.4%, respectively). In connection with that, energy of rumen content was higher by about 22.22% in group of sheep fed with stuff with livex addition and by about 7.41% in group fed forage with blood meal addition. The using of livex as an addition to fodder caused increase of the rumen fermentation efficiency and also regulation of non-glucogenic ratio of volatile fatty acids.