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Two experiments were carried out to investigate the effect of the time of oviposition on egg quality characteristics in two different housing systems (cages vs. litter). ISA brown hens from 20 to 64 weeks of age were housed in battery cages (550 cm²/hen, 19 526 laying hens in the house) and on deep litter (7 hen/m², 4 652 laying hens in the house). In both houses, eggs were collected daily at three oviposition times 06:00, 10:00 and 14:00 h. Every four weeks, 90 eggs for each house (30 eggs for each oviposition time) were used for egg quality assessment. The results indicated that in cages the highest percentages (P ≤ 0.001) of normal (74.47%), non-standard (0.85%) and cracked (1.80%) eggs were laid in the early morning (06:00 h). On deep litter, however, the highest percentages (P ≤ 0.05) of normal sound eggs were produced at10:00 h (35.43%) and at14:00 h (33.03%). In the cage system, the heaviest eggs (63.01 g) were laid in the early morning (06:00 h) and the highest shell percentage (10.33%) was in eggs laid in the afternoon and also at 10:00 h (10.31%). On the other hand, in the litter housing system, the time of oviposition had no significant effect on egg weight and eggshell quality characteristics except for shell thickness. Morning eggs had greater shell thickness (0.398 mm) than afternoon eggs (0.390 mm). In cages and on litter, statistically significant differences in albumen height, albumen index and Haugh Units were observed between early morning eggs and afternoon eggs and data showed a pattern of relatively higher albumen quality for eggs collected in the afternoon in both systems.

Humoral immunity has an important role during the maturation and development of the functional properties of spermatozoa. Spermatozoa may be exposed to antisperm antibodies in semen and in cervical, ovarian follicular and fallopian fluid. Antisperm antibodies can be complement-fixing or non-fixing and may affect the reproductive functions in a number of ways. Although the antisperm antibody alone can cause sperm agglutination, complement fixation is required for their immobilization. Therefore, the complement activation might be a "keystone" for the better understanding of "sperm humoral immunity" and some types of infertility. Recently, three cell surface molecules (CD molecules - CD46, CD55, CD59) present on many tissues in male and female reproductive tracts and gametes have been identified. These proteins belong to the family of complement regulatory proteins which could regulate the function of a complement system by cleavage of complement cascade in discrete sites of both activation ways (classical and alternative). In this review, the particular mechanisms of activity of complement regulatory proteins are presented as well as their function in a fertilization process and expression in human and animal tissues and organs.

Amino acid content before and after heat treatment was assessed in grain of six selected amaranth varieties and four species: Amaranthus cruentus, A. hypochondriacus, A. caudatus and A. hybridus, cultivated in the Czech Republic. High content of Lys and Arg was detected in both heat treated and untreated grains, as well as satisfactory content of Cys and lower levels of Met, Val, Ile and Leu. The latter three amino acids appear as limiting. Chemical scores of essential amino acids and essential amino acid index (EAAI) were determined. EAAI value of 90.4% shows the favourable nutritional quality of amaranth protein, which is almost comparable with egg protein. Heat treatment by popping at 170 to 190°C for 30 s resulted in decreased EAAI to 85.4%. Of the essential amino acids under study, Val and Leu contents decreased significantly (P < 0.05). The relatively high content of essential amino acids in amaranth grain predetermines its use as a substitution of meat-and-bone meals.

Two ruminally cannulated Jersey cows were used to determine in situ ruminal degradability and intestinal digestibility of raw (E0) soybeans and soybeans extruded at 145°C (E145), 155°C (E155) and 165°C (E165). The degradation of dry matter (DM) and crude protein (CP) was estimated using nylon bags suspended in rumen for 2, 4, 8, 12, 16, 24 and 48 h calculating the effective ruminal degradabilities (ERD) for an assumed outflow rate of 0.06/h. Four extra sample bags were incubated for 12 h to determine CP digestibility using the mobile nylon bag method. Cows were fed a ration of 30% concentrate and 70% meadow hay. Soybean extrusion at all temperatures decreased the effective protein degradability significantly (P < 0.05). Soybean processing at the highest heat input (E165) decreased ERD (44.0%) in the rumen significantly while the values for E145 and E155 were similar, 50.8 and 50.3% respectively. Soybean extrusion at all tested temperatures was followed by a significant (P < 0.05) reduction in the proportion of the rapidly degraded DM and CP fractions a, and both the increased proportions and reduced breakdown rate (c) of the fraction b. The intestinal protein digestibility values of the rumen-undegraded protein of extruded soybean were somewhat higher, however the observed differences between treatments were not significant (P < 0.05). Estimated intestinal digestibilities were 87.2, 89.7, 92.0 and 92.6% for E0, E145, E155 and E165, respectively.

There is a constant increase in demand for large numbers of high-quality oocytes of domestic mammals for various reproductive biotechnologies. Prolonged in vitro culture represents one of the many possible ways of meeting this demand. However, oocytes further cultured in vitro after reaching the stage of metaphase II undergo the complex process called "ageing", which decreases the quality of oocytes. The aim of the present study was to improve the culture conditions for in vitro matured porcine oocytes by supplement of the epidermal growth factor (EGF) or the insulin-like growth factor 1 (IGF-1) in order to reduce the adverse effects of ageing. Supplement of either EGF or IGF-1 had no significant effect on the ageing of porcine oocytes. Significant effects were demonstrated when the oocytes were cultured with both EGF and IGF-1. A combination of 10 µg EGF/ml with 25 ng IGF-1/ml was the most effective. Oocytes aged under these conditions retained very good developmental competence. We observed development to the morula (21%) or blastocyst (25%) stage in oocytes aged for 1 day with EGF and IGF-1. Porcine oocytes matured in vitro are more resistant to the ageing when cultured in the presence of both EGF and IGF-1 and these conditions retain an elevated developmental competence for a certain time.

A study was conducted to determine the relationship between abdominal fat and the intake of methionine deficient diet in broilers. In this study, 66 male broilers at the age of 35 days were used. They were divided into two groups (control, n = 13, and methionine deficient group, n = 53) and all birds were housed in individual pens. During the experiment, normal and deficient diet contained 0.55% and 0.25% methionine, respectively. Control group was fed normal diet for 19 days. Treatment group received methionine deficient diet for 4 days and normal diet for 15 days. Body weight and feed intake were recorded daily. High (HG) and low (LG) groups were theoretically created according to the rates of decreases in individual feed intake. Percent decrease in feed intake of HG and LG groups was 29.4 ± 2.0 and -1.3 ± 1.7, respectively. Abdominal fat in HG and LG groups amounted to 1.62 ± 0.1 and 1.73 ± 0.2%, respectively. The feed conversion ratio of HG and LG groups was 3.1 ± 0.1 and 3.4 ± 0.2, respectively. There was a negative correlation (-0.45 in HG and -0.43 in LG) between the percent decrease in feed intake and abdominal fat.

Enterococci (58) from faeces of rabbits of various age (from 2 months to 3 years) and 5 different rabbit farms were isolated and tested for survival in the presence of oxgall, lactic acid production, urease activity, resistance to low pH as well as their binding ability was tested. Fifty percent of enterococcal isolates were identified as Enterococcus faecium, 19% as E. faecalis. All strains showed good survival in the presence of 5% oxgall. The urease activity of isolates was in the range from 0.013 to 17.13 nkat/ml, only E. faecalis EE229 strain did not produce any urease. The survival of strains was tested at pH 3.0 and the percentage of their survival ranged between 62.0% and 90.0%. E. faecium EF1819 strain was found to show the best survival ability at low pH. Particle agglutination assay values of selected enterococci expressed only negative (0) or weakly positive (1) binding of heparin, bovine fibrinogen, porcine fibronectin and lactoferrin. Based on the results, most of the selected enterococci could be promising probiotic feed additives.

This study deals with effects of pressing of ensiled sugar-beet pulp and of application of a chemical preservative on the quality of fermentation process. The experimental silages had a better sensory evaluation than the control ones. In silages treated chemically with a mixture of acids, statistically significantly (P < 0.01) higher dry matter content, lowest pH value, the value of lactic acid and the lowest content of all acids in dry matter were found after 180 days of storage from the beginning of the experiment. The statistically significantly (P < 0.01) highest lactic acid content (43.39 ± 1.25 g/kg DM) was determined in the control pressed silage. The highest LA/VFA ratio (1.40 ± 0.18) was calculated for non-pressed experimental silage (D - 3 l/t of KEM). As compared with untreated control the highest percentage (P < 0.01) of lactic acid and of all fermentation acids was found out in silage D treated with 3 l/t of KEM (58.18 ± 0.47 g/kg DM). Undesirable butyric and propionic acids were not found in chemically treated silage samples (C, D, E, F). However, the highest (P < 0.01) contents of butyric acid (26.37 ± 0.91 g/DM) and propionic acid (4.58 ± 0.78 g/DM) were measured in untreated non-pressed silage samples (B). The highest (P < 0.01) contents of acetic acid and ethanol were found in control silage samples. The quality of these silages was evaluated as very low.