Biochemical changes in sows after eleven or more farrowings.

The animals examined were 30 sows after eleven or more farrowings (pluriparous sows) and 26 primiparous sows. The pluriparous animals were 75.1 months old on the average and had farrowed an average of 13.23 litters. The mean age of the primiparous sows was 12.8 months. The blood sera of pluriparous sows had higher concentrations of total protein and urea and lower levels of 11-hydroxycorticosteroids (11-OHCS) and lower aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase activities than those of primiparous sows. The pluriparous sows showed mild hypoglycaemia and hypocholesterolaemia. When insulin was injected i.m. in the dose of 1 I.U. per kg body mass, a decrease in blood serum glucose, total protein and potassium levels was recorded 60 min later in both pluriparous and primiparous sows; a significant rise in 11-OHCS concentration occurred only in the primiparous sows. It was concluded that the response of the hypothalamo-pituitary-adrenal axis in pluriparous sows to an insulin load is reduced. Studies of pluriparous sows contribute to a better understanding of the ontogenetic development of pigs throughout their postnatal development.

[Metabolic test in pigs with experimental mycobacteriosis fed different amounts of nutrients]. / Metabolický test u prasat pri experimentální mykobakterióze a odlisném príjmu zivin.

Three trials were conducted with pigs at different levels of nutrition. Seven groups of pigs were perorally infected with a suspension of M. intracellulare. Changes in 12 biochemical parameters of metabolism were studied in blood plasma or serum for 98 to 111 days. In comparison with the group of non-infected animals or with the situation prior to infection, the test pigs showed irregular and temporary changes in a number of metabolites, most frequently an increase in the concentration of urea, cholesterol, iron and vitamin A. In the majority of cases, the results are considered as non-typical of infection processes. It was also in relation to clinical and production parameters that the induced mycobacteriosis was regarded as a condition not disturbing, or just insignificantly influencing, the metabolism of slaughter pigs and the economy of their production. The changes in tocopherolaemia, reduction in alkaline phosphatase activity, increase in the total concentration of protein, albumin and cholesterol were related to the development of the pigs at the weight from 20 to 80 kg, rather than to the infection process. The limited intake of proteins or vitamin supplement allowed for verifying the possibility of using some biochemical parameters for practical diagnosis.

[Heat dissipation through the floor in piglet housing]. / Odvod tepla podlahou v dochovnách selat.

Trials were performed in 1980 and 1981 to test a new methodical procedure of measuring heat flow with Alfameter and to evaluate the dissipation of heat via the floor in piglet finishing houses with three large pig herds. It was demonstrated during the period of the study that slatted floors dissipated much more heat from the house, as compared with solid floors. The comparison of the density of heat flow over steel slats and plastic slats showed that the plastic slats wasted less heat: in the winter season the difference was 65 to 125 W/m2 and in summer 20 to 75 W/m2. In the houses with steel slats the comparison of heated and unheated lying place showed that the heat flow emitted from the lying place reduced the dissipation of heat via the slats.

[The effect of qualitatively different nutritional intakes on the development of experimentally induced atypical mycobacteriosis and the appearance of indicators in pigs]. / Vliv kvalitativne odlisného príjmu zivin na rozvoj experimentálne vyvolané atypické mykobakteriózy a na produkcní ukazatele u prasat.

A single infection with the culture of M. intracellulare at a rate of 0.1 mg per kg of weight in pigs fed the A 1 and SOL mixtures and the subsequent development of clinically confirmed mycobacteriosis did not exert any significant influence on the performance of the animals, as compared with the non-infected animals. The metabolically determined coefficients of nutrient digestibility in the SOL mixture determined in the animals on the 70th and 91st days from infection were almost the same as those in non-infected animals. The absence of animal protein and biofactor supplement in experimental mixtures adversely affected the performance of the pigs but exerted no unfavourable influence on the development of atypical mycobacteriosis after the administration of 0.01 mg or 0.1 mg of the culture of M. intracellulare per kg of body weight. No elimination of atypical mycobacteria in the faeces was demonstrated in the groups fed mixtures with biofactor supplement. The feeding of infected pigs with the COS 2 and A 1 mixtures, compared with the use of the experimental mixtures with a lower content of nitrogen compounds and vitamins and a higher content of fibre and energy, influenced the parameters of performance but did not result in a different patho-anatomic and bacteriological picture after mass-scale infection (1 milligram of culture per kg of weight).

[Loss of heat through the skin in piglets in pigsties with and without windows]. / Výdej tepla kuzí u selat v okenní a bezokenní dochovne.

In 1980 and 1981 tests were performed to verify the new methodical procedure of measuring heat flow by means of Alfameter and to evaluate the liberation of heat from the skin of piglets kept in two-storeyed cages in the finishing houses of the TEROZ TACHOV type. One of these houses was windowless, the other had windows. The temperature, humidity and flow rates of the air inside the houses were measured at the same time. The comparison of the two types of houses showed that under the given conditions the houses with windows implied a higher rate of cooling and a higher density of heat flow over the skin of the weanlings. In the windowed as well as windowless houses, the pigs in the upper row of cages showed a higher rate of heat liberation from the skin, as compared with the lower row. The piglets kept in the windowed house had lower gains and lower mortality rates.