The effect of MgSO4 addition and the increasing doses of calcium and phosphorus during ending drying period on the occurrence of hypocalcaemia and hypophosphataemia in dairy cows.

The aim of the presented study was the estimation of optimal Ca and P levels applied before calving together with anionic salt addition, as an element of hypocalcaemia and hypophosphataemia prevention. The experiment was carried out during the dry period on 48 cows with similar milk yield in the previous lactation. Cows were divided into four groups. In group I (control) the amount of minerals was in accordance to NRC standards. In experimental groups (groups II-IV), two weeks before calving, cows received 140 g/day/head of hydrated magnesium sulphate to achieve dietary cation-anion difference at the level of about 50 mEq/kg DM. In groups II and III cows received calcium carbonate (100 g/day) 10 days a.p. (antepartum) (group II), or 5 days a.p. (group III), while cows in IV group received dicalcium phosphate (100 g/day) for 5 days a.p. Application of MgSO4 x 7H20 significantly affected the urine pH of cows from group III and IV 4-5 d. before calving - 6.45 and 6.81, respectively. The acidification of urine was observed after calving in group IV (7.13). In cows from group II (100 CaCO3 10 days a.p.) urine pH decline was not found (7.97-7.75). In that group the incidences of hypophosphatemia were noted (blood serum inorganic P level 1.41-1.46 mmol/1). Addition of magnesium sulphate prevented hypocalcaemia occurrence -- 4-5 d. before calving the concentration of ionized Ca in blood serum was 1.11, 1.13 and 1.16 mmol/1 (respectively for group II, III and IV). Reproductive functions were significantly improved after the application of CaCO3 and CaHPO4 for 5 days a.p. in comparison with control and group II -- progesterone concentration in the blood serum on the 45th day of lactation was 1.396 - 1.409 versus 0.799 - 0.401. The correlation between progesterone and inorganic P level in serum was almost significant. Based on the obtained results a treatment optimal in prevention of hypocalcaemia and hypophosphataemia is the application of 50 g CaCO3 and 50 g of CaHPO4 for the last 5 days of the dry period together with MgSO4 x 7H20 given for 14 days a.p.

The influence of administration of biotin and zinc chelate (Zn-methionine) to cows in the first and second trimester of lactation on their health and productivity.

In cattle, the prevention of diseases might be possible using dietary methods, with nutritional optimization of feed rations. For years significant influence has been associated with the addition of biotin, methionine and zinc (each given individually, or as chelate - Zn-methionine). The aim of this study was to evaluate the influence of biotin or biotin + Zn-methionine additives on the health and performance of cows, in the first and second trimester of lactation. This study was carried out in 3 groups of cows, 30 animals in each group. In the first group cows were fed the usual fodder used on the farm. In the second group biotin at 10 mg/day/cow was added. In the third group both biotin at 10 mg/day/cow and Zn-methionine at 5 g/day/cow were added. The administration of biotin increased the milk yield and reduced the occurrence of retained placenta, as well as endometritis puerperalis. However, the high doses of biotin suppressed ovulation and oestrus symptoms in the investigated cows (low progesterone levels on days 15, 21 and 45 after calving). Zn-methionine in comparison to biotin had a lower effect on the milk yield in the cows. Moreover, its supplementation improved the milk content, as well as some of the blood parameters; it also decreased the number of somatic cells in milk. The concurrent administration of biotin and zinc-methionine seemed to be a good method for the prophylaxis of subacute mastitis and for the improvement of the high yielding dairy cows' productivity.

The effect of feeding piglets up to the 100th day of their life with peat preparation on their growth and physiological and biochemical indices.

The experiment was carried out on a group of 300 piglets. During experiment the effect of supplementation with peat preparation coming from different charges on productivity, selected productive and biochemical indices was examined. All these indices were compared with a negative and positive control. A positive effect of supplementation with peat preparation in amount of 300 mg/kg of mixture on body weight increase and physiological and biochemical indices was found. The examined peat preparation coming from different charges demonstrated different effect which shows that it was not an entirely homogeneous material.

Influence of animal and plant fat addition in pasture and winter feeding of high yielding cows at first stage of lactation on productivity and physiological profiles.

200 g of fat in the form of greased wheat bran, was given cows during pasture feeding. For winter feeding on hay and silages the amount was 400 g of greased wheat bran or 400 g of oil in ground rapeseed per day and per animal. Influence of the fat addition on the yield and milk composition was observed in the case of pasture experiment. No such influence was observed in the winter feeding. Addition of fat advantageously influenced the chemical constituents in the cow blood in both experiments.

The effect of carotene and vitamins A and E supplementation on reproduction of sows.

The effects of synthetic and natural beta-carotene as well as vitamins A and E supplementation on the fertility of sows and number of piglets in a litter were the subject of our studies. The sows fed beta-carotene had from 2 to 4 more piglets in a litter. Vitamin E had a harmful influence on beta-carotene action. It was found that synthetic beta-carotene and vitamin A increased the number of viable embryos and yellow bodies in the sows slaughtered on the 28th day of gestation, moreover beta-carotene subsequently improved the fertility of sows in the next reproductive cycle.

Cell shape and organization of the contractile apparatus in cultured adult cardiac myocytes.

The isolation and culture of adult cardiac myocytes has proved to be an ideal model system to explore myocardial biology at the cellular level. A major criticism of this model, however, has been that organ-specific characteristics such as cell shape and subcellular structural organization cannot be retained in vitro for prolonged periods of time. Encasing freshly isolated myocytes in a matrix of calcium alginate enables one to maintain the rod-like, three-dimensional (3D) shape of the cultured myocyte. Such preparations more closely resemble their in vivo counterparts with respect to the organization of the contractile apparatus, the transverse tubular system and the sarcoplasmic reticulum than do heart cells cultured on a two-dimensional (2D) plastic surface. Stereologic measurements reveal that myofibrillar volume density (VvMYF) decreases in both non-beating preparations over a 2-week interval, but VvMYF is conserved in cells cultured in an alginate matrix when compared to those myocytes maintained on a laminin-coated substratum. The present observations suggest that in the absence of contractile function myofibrillar atrophy appears responsible for the decline in VvMYF in alginate (3D) preparations, whereas atrophy and subcellular remodelling probably mediate the myofibrillar loss and reorganization that develops when adult heart cells are cultured on a 2D surface.

[Evaluation of the indicators of protein, carbohydrate and mineral metabolism in the blood of cows fed supplementary high-energy food]. / Ocena wskazników przemiany bialkowej, weglowodanowej i mineralnej w krwi krów mlecznych dokarmianych energetycznie.

Cows of the white-black breed from the Sudeten piedmont were divided into two groups: control and experimental. Both groups were fed the same basic fodder, e.g. pasture, green forage of clover and maize, and hay; afterwards they were fed grass silage, hay and beets. Maize forage, containing little fibrin, lot of starch and soluble carbohydrates, was substituted by grass silage with little starch and soluble carbohydrates, but rich in cellulose and hemicelluloses. So, energetic value of the food was different. The chosen chemical indices were estimated during the change of fodder from pasture to winter silage and hay. Cows from the control group were fed additionally, one month before calving, 1 kg of the protein food (bruised barley) without urea, whereas cows from the experimental group were fed additionally with bruised barley, in the amount of 1.5-3 kg, when giving less than 4000 l of milk, and 2.5-4 kg, when giving over 4000 l of milk. The amount of food increased by 0.5 kg every week beginning with smallest dose. This additional feeding had positive influence on the milk production, especially in the 2nd and 3rd month after calving (2.3 kg during 4 months after calving), and improved the effectivity of fertilization after the first insemination. The chemical composition of the milk has not been changed significantly; the total protein and its fraction, levels of urea, Ca, Fe and Mg in the blood plasma have not been changed. Only the level of ketones in blood decreased a little. During the transition period, green forage feeding caused the increase of the glucose level in blood to 60 mg% (50 mg% in winter). Additional energetic feeding of cows before calving improved productivity indices and did not change the internal body balance (homeostasis).

[The protein-synthesizing function of the liver in dairy cows fed feed with the addition of various urea preparations and different doses of urea]. / Czynnosc bialkotwórcza watroby krów mlecznych zywionych pasza z dodatkiem róznych preparatów mocznikowych i zróznicowana dawka mocznika.

It was compared the effect of different preparations containing urea on the productivity and on the blood content of the biochemical compounds informing about protein synthesis activity in the liver of milk cows. The following preparations were added alternatively to the food to 28 cows in a quantity equal with 150 Gm in the first year and with 200 Gm of pure urea in the second year of experimentation for cow and for day: 1. Melwit--a liquid food supplementation containing 5 per cent of urea, 2. Walczan--"Sterea"-like preparation with 30 p.c. of urea, 3. Ekstruder--"Golden-Pro"-like preparation with 20 p.c. of urea and 4. BW preparation (concentration) for dairy cows containing only plant protein, without urea. In the plasma of all animals was observed the increase of urea, total protein and albumin content and of the activity of following enzymes: AP, AAP, Arg, LAP, AspAT and of A1AT. The content of total and of direct bilirubin in plasma did not change significantly. All examined compounds did not exceed the physiological range. The greatest changes were observed after feeding with Extruder. The physiological decline of milk production after calving was smallest in group fed with Walczan (2.4 litres) and greatest in Ekstruder group (4.4 litres) when in Melwit 3.4 and in BW 3.5 litres was noticed. The authors stated that the most suitable form of preparation containing urea was Walczan in the first place and Melwit in the second.