[Content of chemical elements in the liquid manure of swine at a treatment plant using biological purification]. / Sudurzhanie na khimichni elementi v techen tor ot svine v prechistvatelna stantsiia s biologichno prechistvane.

An atom absorption spectrophotometer was used to study 13 chemical elements in samples taken at the entrance of the purification station, at the mechanical step exit, at the biostep exist, and at the laguna exit as well as following treatment of the solid fraction in open surface purification and drying plots. It was found that part of the biogenic chemical elements remained in the liquid fraction after purification and were hazardous in terms of eutrophication of the water receptacle. A technology was worked out to treat the solid fraction, however, it did not provide for preserving the biogenic chemical elements. This lowered the qualities of the fraction in enriching the soil.

[Enzyme constellation in cows of the Simmental crossbreed and Black Pied breed during the dry period and lactation]. / Enzima konstelatsiia pri kravi ot porodata Simentalski melez i Chernoshareno govedo pri sukhostoini i laktirashti kravi.

Studied was the enzyme constellation, resp., activity of alkaline phosphatase (AP), glutamate-oxaloacetic transaminase (GOT), glutamate-pyruvate transaminase (GPT), aldolase (ALD), leucin-aminopeptidase (LAP), cholinesterase (CE), creatine phosphokinase (CPK), lactate dehydrogenase (LDH), ornithine carbamoyltransferase (OCT), and guanase (G) in a total of 360 clinically normal and lactating and dry cows of the Black-and-White and Simmental crossbreeds. Characteristic quantitative changes were found with GOT, GPT, ALD, LDH, and CPK both over the dry period and over the entire period of lactation. The activity of LAP, AP, OCT, and G was not influenced by the functional status of the animals. In the course of the analyses there were changes in the serum ALD, CE, and GOT, associated with the breed. The enzymes referred to were studied with a view to establishing their normal parameters needed for the practice as the base to demonstrate preclinical disturbances in individual organs and tissues of the cows during pregnancy and the puerperium.

[Effect of density during the raising of broilers on their morbidity and mortality]. / Vliianie na gustota pri otglezhdane na broileri vurkhu zabolevaemostta i smurtnostta.

Studied was the effect of biotic ecologic factors and their dynamic at varying density of raising broilers at equal abiotic factors. The experiments were carried out in two production buildings of the same type. A cage of low density (16.6 birds/m2) was placed on a premise of high density (23.6 birds/m2), and vice versa--a cage of high density (23.6 birds/m2) was placed on a premise of low density (16.6 birds/m2). It was found that density of raising had a definite bearing on both morbidity and mortality rates. At lower density they ranged from 6.84 to 9.74 per cent, and at higher density--from 10.67 to 14.07 per cent, whereupon by the end of the fattening period certain changes were observed in the behaviour of birds (anxiety, inadequate locomotion movements). Diseases that were transmitted transovarially and diseases such as cannibalism affected greater number of birds when these were raised at higher density. It was concluded that density of raising influenced both the abiotic and biotic factors, and its integral effect could be evaluated as that of a stress factor when higher numbers of birds were raised on unit area. This invariably had a bearing on the rates of morbidity and mortality. The approach that has been used so far in optimizing the microclimatic parameters only (at higher density of raising) was shown to be partial as the effectiveness of production is governed by the action of biotic factors as well. This makes it necessary to study their effect.

[Effect of environmental factors on the body response reactions in newborn calves]. / Vliianie na niakoi faktori na vunshnata sreda vurkhu otvetnite reaktsii na organizma na novorodenite teleta.

Studied was the role of the general state and the adaptability of newborn calves under the effect of some environmental factors (temperature and relative humidity) that had no optimal values in the onset of diseases caused by occasionally pathogenic agents. It was found that under conditions that were one and the same for all calves the metabolic and functional responses were varying. Those of the animals with which the nervous-and-hormonal system was more unstable manifested a specific biochemical-and-functional response through which no'equilibration' was achieved with the environment, and they got sick. Others, exhibiting metabolic processes that were stronger and more stable as the result of the involvement of more powerful regulatory mechanisms inherent to a 'neuro-functional' animal organism could adapt successfully to the nonoptimal factors of the environment. Such animals were not shown to be susceptible to the effects of conditionally pathogenic agents.

[Age-related dynamics of blood biochemical indices in Black Pied calves]. / Vuzrastova dinamika na niakoi biokhimichni pokazateli na kruvta na teletata ot chernozharenata poroda.

The level of a number of blood indices was followed up in Black-and-white calves from the first day after birth up to the sixth month such as hemoglobin, 2,3-diphosphoglycerate, blood sugar, phosphorus, and total, ionized, and protein-bound calcium, with total protein. The calves were clinically normal and were raised in various regions under routinely adopted zoohygiene, technologic, and microclimatic conditions and parameters, and were offered rations that were currently adopted in this country. The dynamic established with the changes of the indices investigated disclosed possibilities of obtaining additional information concerning the state of the animal's organism which proved instrumental in choosing the right prophylaxis in compliance of the respective age period.

[Poultry meat production with varying densities in raising the broilers]. / Vurkhu proizvodstvoto na ptiche meso pri razlichna gustota na otglezhdane na broilerite.

Tests were carried out at two densities of raising the broilers on productional premises--16.6 and 23.6 per 1 m2 of flooring. Both the prophylactic programme and the conditions of tending and feeding were one and the same on the premises used. Each one of these was supplied with a cell in which birds were kept at the same density value as that on the other premise. Thus, four groups were formed in all: I--broilers kept at the rate of 16.6 per sq. m, II--broilers raised on the premise at 23.6/m2, III--broilers kept in a cell at 16.6 on the same premise where the other birds were kept at 23.6, and IV--broilers kept at 23.6 per sq. m. on the premise where the rate concerning the other birds was 16.6. The basic integral indices of the production effectiveness as well as the bioconversion of the dietary amino acids were followed up. It was found that during the transitional period the lower productional results with the broilers raised at higher densities were due to the action of biotic factors, and, more specifically, to the changes in the homotypical reactions that were the result of the higher density of raising. In the summer season the pesimal effect produced was a complex one, including not only the biotic factors but also the unfavourable action of the temperature and humidity regime.

[Evaluation of abiotic ecological factors and their dynamics at various densities in raising broilers]. / Pretsenka na niakoi abiotichni ekologichni faktori i tiakhnata dinamika pri razlichna gustota na otglezhdane na broileri.

Three productional experiments were carried out in which the broilers were kept on unified premises under one and the same technology, but at various densities of raising: 14.4 and 23.4/sq. m., and 16.6 and 23.6/sq. m. with the second and third experiment. The dynamic, light intensity, and content of toxic gases along with the homogenization of air in the birds' vital zone were followed up. Differences were established which were defined by the higher density of raising, and which, acting as a constellation on the organism might lower the effectiveness of the technologies employed.