Čimbenici koji utječu na sadržaj kolesterola u mlijeku krava hranjenih konzerviranim krmivima TMR sustavom tijekom godine

The aim of this study was to evaluate changes in the cholesterol content in the milk of high yielding cows fed a uniform diet composed of conserved feeds over the whole year. The investigations were conducted on 124 Polish Holstein-Friesian cows, selected fromherd yielding 8457 kg milk with 4,58 % and 3,56 % of fat and protein content, respectively. The cows were maintained in a loose barn and fed ad libitum with TMR (total mixed ration) throughout the year. The diets consisted of corn silage and grass silage (at 50:50 ration on dry matter basis) and concentrates with mineral-vitamin mixture additives. Samples of milk were collected individually from each cow at monthly intervals during the whole year. The cholesterol content in milk (mg/dL) and in milk fat (mg/g) was related to the stage of lactation, season of the year, somatic cell count and fat content, but was not affected by the parity. The cholesterol content in daily milk yield (mg/cow/day) depended also on parity. Even though the cows were fed a uniform diet throughout the year according to the TMR system the cholesterol content in milk differed among seasons.Cilj ovog istraživanja bio je ispitati promjene udjela kolesterola u visokomliječnih krava hranjenih obrokom sastavljenim od konzerviranih krmiva tijekom cijele godine. Istraživanja su provedena na 124 holstein-frizijske krave, odabrane iz stada koje proizvode 8457 kg mlijeka s 4,58 % mliječne masti i 3,56 % proteina, respektivno. Krave su držane u otvorenom tipu staja i hranjene ad libitum s potpuno izmiješanim obrokom (TMR, total mixed ration) tijekom cijele godine. Obrok se sastojao od kukuruzne i travne silaže (50:50, na bazi suhe tvari) i koncentrata s mineralno-vitaminskim dodacima. Uzorci mlijeka prikupljani su pojedinačno od svake krave u mjesečnim intervalima tijekom cijele godine. Sadržaj kolesterola u mlijeku (mg/dL) i mliječnoj masti (mg/g) u vezi je sa stadijem laktacije, godišnjim dobom, brojem somatskih stanica i udjelom masti, ali nije bio pod utjecajem redoslijeda laktacije. Sadržaj kolesterola u dnevnoj količini mlijeka (mg/kravi/dan) ovisi također o redoslijedu laktacije. Unatoč hranidbi krava uniformnom prehranom tijekom cijele godine TMR sustavom, sadržaj kolesterola u mlijeku mijenjao se pod utjecajem sezone

Alcohol in the world of animals

W opracowaniu przedstawiono wiele dowodów na to, że upodobanie do alkoholu jest nie tylko przywarą ludzką, ale także i zwierząt wszystkich gatunków. Zwierzęta żyjące w środowisku naturalnym spożywają różnego rodzaju owoce, nektary, glony morskie i inne produkty roślinne, które ze względu na zawartość łatwo fermentujących cukrów w dojrzałym stadium zawierają także pewną ilość alkoholu. Zapach alkoholu wydobywającego się z dojrzałych owoców w gęstym lesie tropikalnym umożliwiał zwierzętom znalezienie pokarmu, zwiększając tym samym ich szansę na przeżycie. Dieta naczelnych przodków Homo sapiens w znacznej części składała się z owoców, często zbyt dojrzałych, w których cukier uległ przemianie na alkohol. W wyniku procesów ewolucyjnych skłonność ta mogła utrwalić się u naszych przodków i jest przekazywana na współczesne pokolenia. Eksperymentalnie wykazano, że spożywanie alkoholu i jego konsekwencje u zwierząt są podobne jak u ludzi. Szybkość metabolizowania alkoholu przez organizm jest związana z długością okresu jego spożywania. Wyniki badań naukowych wskazują, że ryzyko uzależnienia od alkoholu w 50-60% zależy od czynników genetycznych. Na chromosomach myszy i szczurów zidentyfikowano wiele genów związanych z zespołem abstynencyjnym. Wykazano ujemny wpływ alkoholu na rozwój mięśni, związany z obniżeniem poziomu hormonu anabolicznego (IGF1). Wbrew obiegowym opiniom alkohol nie wpływa na złagodzenie stresu lecz przeciwnie - wzmaga reakcję na stresory. U osób pijących alkohol w mózgu wzrasta zawartość białka, tzw. tkankowego aktywatora plazminogenu, które współpracuje z receptorami w mózgu (NMDA). U osób pijących alkohol liczba tych receptorów gwałtownie rośnie, lecz ich aktywność jest blokowana przez alkohol. Po zaprzestaniu spożywania alkoholu wspomniane receptory uaktywniają się, co prowadzi do wystąpienia stanu groźnego dla życia, określanego mianem "delirium tremens". Zdaniem naukowców alkohol jest jedyną substancją uzależniającą, po odstawieniu której można umrzeć.This article presents ample evidence that the taste for alcohol is not only a human vice, but also the animals of all species. Animals living in the wild environmental eat different types of fruit, nectar, seaweed and other vegetable products, which due to the content of readily fermentable sugars in the mature stage also contain a certain amount of alcohol. The smell of alcohol emanating from the ripe fruit in the dense tropical forest enabled the animals to find food, thus increasing their chance of survival. Diet of primate ancestors of Homo sapiens in a large part consisted of fruit, often too ripe, in which sugar has been converted to alcohol. As a result of evolutionary processes, this tendency could prevail in our ancestors and had been passed to the modern generations. Experimentally demonstrated alcohol consumption and its consequences in animals are similar to those in humans. The rate of alcohol metabolism in the body is associated with the duration of consumption. Research results indicate that the risk of alcoholic addiction in the 50-60% depends on genetic factors. On the chromosomes of mice and rats several genes associated with the syndrome "abstinence from alcohol" were identified. Negative effects of alcohol were also demonstrated on the development of muscle, associated with decreased levels of anabolic hormone (IGF1). Contrary to popular belief, alcohol does not affect the relaxation of stress, instead increases the response to stressors. In brains of people who drink alcohol were observed increases in the content of the protein called tissue plasminogen activator, which cooperates with receptors in the brain (NMDA). The number of these receptors is growing rapidly, but their activity is blocked by alcohol. After the cessation of alcohol use these receptors become activated, which leads to development of life-threatening condition known as "delirium tremens". It is believed that alcohol is the only addictive substance, which after stopping of its consumption may cause deaths

Expression and polymorphism of defensins in farm animals

Due to their activity against bacteria, viruses, and fungi, antimicrobial peptides are important factors in the innate resistance system of humans and animals. They are called "new generation antibiotics" for their potential use in preventive and therapeutic medicine. The most numerous group of antimicrobial peptides is a family of cationic peptides which include defensins and cathelicidins. Among them the most common are peptides with a beta-sheet structure containing three intra-molecular disulphide bonds, called defensins, comprising three classes: alpha, beta, and theta. The class of beta-defensins is the largest one. Their transcripts have been found in many tissues of humans and animals. The aim of this paper is to present the current knowledge about antimicrobial peptides from the defensin family in farm animals, their expression, polymorphism, as well as the potential of their use as genetic markers of health and production traits

Factors affecting the cholesterol content of milk of cows fed conserved feeds in a TMR system throughout the year

The aim of this study was to evaluate changes in the cholesterol content in the milk of high yielding cows fed a uniform diet composed of conserved feeds over the whole year. The investigationswere conducted on 124 Polish Holstein-Friesian cows, selected fromherd yielding 8457 kg milk with 4,58 % and 3,56 % of fat and protein content, respectively. The cows were maintained in a loose barn and fed ad libitum with TMR (total mixed ration) throughout the year. The diets consisted of corn silage and grass silage (at 50:50 ration on dry matter basis) and concentrates with mineral-vitaminmixture additives. Samples of milk were collected individually from each cow at monthly intervals during the whole year. The cholesterol content in milk (mg/dL) and in milk fat (mg/g) was related to the stage of lactation, season of the year, somatic cell count and fat content, but was not affected by the parity. The cholesterol content in daily milk yield (mg/cow/day) depended also on parity. Even though the cows were fed a uniform diet throughout the year according to the TMR system the cholesterol content in milk differed among seasons