Antibiotic resistance and virulence factors in mesophilic Aeromonas spp. from Czech carp fisheries.

AIMS: The aim of this study was to determine phenotypic and genotypic resistance, virulence and clonal relationship of aeromonads and related species isolated from Czech carp fisheries. METHODS AND RESULTS: Forty-nine isolates obtained from a total of 154 fish from three breeding facilities were species identified using matrix-assisted laser desorption/ionization time of flight and the sequencing of the rpoB housekeeping gene. Most Aeromonas isolates were identified as Aeromonas veronii (94%, n = 34). Susceptibility to six antibiotics (oxytetracycline, flumequine, florfenicol, sulphamethoxazole/trimethoprim, enrofloxacin and oxolinic acid) was tested using the disc diffusion method. The presence of resistance genes and virulence factors was verified by PCR and sequencing, and the clonal relationship was analysed using pulsed-field gel electrophoresis (PFGE). Phenotypic resistance to one or more antimicrobials was found in 32 isolates (65%, n = 49). Resistance to oxytetracycline was the most common (41%) and associated mainly with the presence of tet(E) gene, while the percentage of isolates resistant to florfenicol was low (2%). Isolates carried one to five of the tested virulence factors and showed high diversity of PFGE profiles. CONCLUSIONS: Since the highest percentage of antimicrobial resistance in aeromonads was found for oxytetracycline and the lowest percentage for florfenicol, it is suggested that florfenicol could be an adequate treatment alternative in carp fisheries. SIGNIFICANCE AND IMPACT OF THE STUDY: Increasing resistance of aeromonads to commonly used antimicrobials has become an emerging problem in fisheries. This study was conducted in relation to the practical needs to identify a suitable antibiotic as an alternative to oxytetracycline.

Haematological indices are modulated in juvenile carp, Cyprinus carpio L., exposed to microcystins produced by cyanobacterial water bloom.

This study evaluated the influence of toxic cyanobacterial water blooms on the blood indices of the common carp, Cyprinus carpio L. Experimental fish were exposed to a natural population of cyanobacterial water blooms (mainly Microcystis aeruginosa and M. ichthyoblabe), which contained microcystins [total concentration 133-284 µg g⁻¹ (DW), concentration in water 2.8-7.4 µg L⁻¹]. Haematological indices showed marked changes in fish exposed to the cyanobacterial population in comparison with the control group. Statistical evaluation of the influence of cyanobacterial water blooms on biochemical indices of the juvenile carp showed a distinct decrease in albumin, alanine aminotransferase, total bilirubin, calcium, cholesterol, glucose, phosphorus and iron when compared to controls. Values of red blood counts [haemoglobin, haematocrit (PCV), mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration] and lactate were significantly increased compared to controls. After exposure to cyanobacterial water bloom, the carp were kept in clean water to monitor the persistence of biochemical indices. The influence of cyanobacterial populations on calcium, cholesterol, glucose, lactate, phosphorus and PCV persisted up to 28 days after conclusion of the experiment. Duration of exposure, toxicity and density of cyanobacterial water blooms had an important impact on individual haematological indices.

Organochlorine pollutants in chub, Leuciscus cephalus, from the Svratka River, Czech Republic.

The aim was to evaluate the extent of pollution of the Svratka River with organochlorinated pollutants using the chub (Leuciscus cephalus) as a suitable bioindicator of the river contamination. The sum of 7 PCB congeners was found in range of 7.6-93.8 ng/g (with median of 31.7 ng/g) wet weight (ww), DDTs of 2.9-93.8 (29.9) ng/g ww, HCHs isomers of 0.1-5.3 (1.0) ng/g ww, HCB of 0.3-8.4 (2.2) ng/g ww and OCS of <0.1-0.5 (0.1) ng/g ww. Our results confirm predominance of metabolite DDE and higher-chlorinated PCB congeners and are comparable with similar studies and findings within the Czech Republic.

[Verification of the usefulness of Estrophan inj. Spofa in the control of reproductive parameters in sows after weaning of piglets]. / Overení pouzitelnosti príravku Oestrophan inj. Spofa k ovlivnení reprodukcních parametru prasnic po odstavu selat.

Cloprostenol, a prostaglandin F2-alpha analogue, used in the Czechoslovak preparation Oestrophan ing. Spofa was tested by a new nontraditional use. The effect of cloprostenol use on reproductive parameters of sows after piglet weaning was followed in a set of 456 experimental and 434 control sows. The effect of single intramuscular instillation of cloprostenol was tested in five partial observations: to multiparous sows at a dose of 175 micrograms on the day of weaning (experimental group no. 1), on day 1 after weaning (group no. 2), 500 micrograms on day 1 after weaning (group no.3), to primiparous sows at a dose of 500 microgram on day 1 after weaning (group no. 4). The treatment used in group no. 4 was also applied to 42 primiparous sows kept on a farm with regular occurrence of post-weaning anoestria of sows (experimental group no. 5). These parameters were evaluated: dynamics of oestrus onset within five, and/or ten, days after weaning, average length of the weaning--first insemination interval, conception rate after the first insemination in dependence on terminated deliveries and parameters of piglet litter. Cloprostenol application did not have a statistically significant effect on the evaluated reproductive parameters. The percentage of multiparous, and/or primiparous, sows in which the oestrus onset was not detected by the 10th day after weaning, did not show any large differences in the various experimental and control groups (17.09 vs. 16.55%, 23.53 vs. 32.56%, 13.66 vs. 18.13%, 29.54 vs. 30.30%; P > 0.05). On the farm with regular occurrence of post-weaning anoestria there were 73.81% of primiparous sows with oestrus onset after cloprostenol instillation and 71.43% primiparous sows without treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

[Experimental chronic phenylmercuric chloride poisoning in pigs]. / Experimentální chronická intoxikace prasat fenylmerkurichloridem.

Four gilts, sisters from one litter, aged 70 days and weighing 20-24 kg, were used for a trial. Two experimental gilts (P) were administered an experimental feed mixture containing phenylmercury chloride (40 mg/kg). Two control gilts (K) were fed the same mixture but without phenylmercury chloride. P gilts began to lag behind in their growth from day 60 of the experiment, they manifested nonphysiological postures (dog's sitting posture), paresis of hind limbs and uncoordinated movements. P gilts had cloudy, orange-brown urine from day 70 and from day 75 they began to suffer from diarrhoea. Mercury (Hg) contents in urine and blood serum of P gilts were irregularly variable: urine 0.58-2.15 mg/l, blood serum 0.02-0.37 mg/l. Hg content in excrements of P gilts fluctuated from 23 to 26 mg/kg. Vitamin A concentrations in blood serum and liver decreased in P gilts. Phenylmercury chloride feeding caused mutagenic changes in peripheral lymphocytes of P gilts (an increase in the number of aberrant cells from 2-3% to 8-9%) and reduced IgA, IgM and IgG immunoglobulin levels in blood serum. Pathological lesions were observed in the colon, kidneys and liver. None of the above-mentioned changes were observed in K gilts. Increased resistance to the negative effects of Hg was found in one experimental gilt. In comparison with K gilts, Hg concentrations in P gilts after 130 days of the experiment increased as follows: 427 times in kidneys, 333 times in liver, 106 times in guts, 71 times in pancreas, 53 times in ovaries, 50 times in muscles, 47 times in bristles and 16 times in the brain.(ABSTRACT TRUNCATED AT 250 WORDS)

[Fertilizing capability of breeding boars by evaluation of the early pregnancy factor in test sows]. / Posouzení fertilizacní schopnosti plemenných kancu hodnocením faktoru casné gravidity u testacních prasnic.

The fertilizing ability of breeding boars was evaluated on the basis of an early pregnancy factor (EPF) determined in the blood serum of test sows by the method of rosette inhibition. The fertilizing ability was tested in ten boars on an insemination farm: the fertilizing potency of 41 ejaculates was evaluated from the percent conception of 105 test sows. The percent conception of test sows was evaluated from the EPF positive findings in the blood serum of these sows in the average range of 8.02 +/- 1.70 days (the range of 2 to 11 days) after insemination and from the recorded deliveries. The evaluation of the fertilizing of boars on the basis of EPF in test sows revealed in most cases the higher fertilization rate than could be found on the basis of the recorded deliveries of test sows. There was an exception to this trend: one breeding boar with a paradoxical finding of the somewhat higher percentage of deliveries recorder in test sows, in comparison with the fertilization ability according to the results of EPF. Identical results of the two criteria of fertilizing ability were recorder in another boar with a small number of tested ejaculates and test sows. The average fertilization of the whole set of the breeding boars, expressed by the average percent conception of all test sows, reached 86.67% on the basis of the EPF positive findings in 2 to 11 days after insemination, and 67.31% on the basis of recorded deliveries. These differences in fertilization are likely to be related to the share of dams and can be ascribed to embryonic mortality.

[Prevention of anestrus in sows after the 1st and 2d parturition]. / Prevence anesterie u prasnic po prvním a druhém porodu.

The procedure of prevention of anoestria after the weaning of piglets was verified in 389 experimental and 332 control sows of the Prestice breed. The set of animals under study included 77 experimental and 122 control primiparae, 68 experimental and 71 control secundiparae, and 244 experimental and 139 control multiparae (i.e. sows with three or more parturitions). The experimental sows were treated with 1000 IU of serum gonadotropin ad usum vet.-Bioveta-(PMSG) the first day after the weaning of piglets and with 300 IU of chorion gonadotropin (HCG) in the Praedyn inj. Spofa preparation together with 1 ml of Dirigestran inj. Spofa (40 micrograms LHRH) 72 hours later. Control sows were not treated with hormones. The treated primiparae and secundiparae respectively, had a significantly higher percentage of oestrus onset within 10 days after weaning and lower occurrence of anoestria over 10 days after weaning by 31.25 per cent (P less than 0.001), and 21.36 per cent (P less than 0.02) respectively as compared with untreated controls. In the set of secundiparae, the studied hormonal treatment speeded oestrus onset by a significant (P less than 0.01) shortening of the interval from weaning to the first insemination by 0.79 day and by a more frequent onset of oestrus within only 5 days after weaning of piglets. The values of the other criteria of reproduction studies, i.e. percentage of pregnancies after the first insemination, total number of born piglets and number of liveborn piglets converted per one litter in treated primiparae and secundiparae did not differ significantly (P greater than 0.05) from the control.(ABSTRACT TRUNCATED AT 250 WORDS)

[Estradiol-17beta in the blood of boars with disorders of sexual potency]. / Estradiol-17 beta v krevní plazme kancu s poruchami sexuální potence.

The levels of oestradiol-17 beta (E2) in the blood plasma were evaluated in 15 boars exhibiting signs of sexual potency disorders and in 20 boars with no such disorders before and after i. v. administration of chorion gonadotropin (HCG). No significant difference (P greater than 0.05) was found in the E2 levels in the blood plasma of the boars of the two groups before HCG administration. Two hours after the i. v. injection of 500 I. U. of HCG, an insignificant increase in the basal levels of E2 was recorded, reaching on the average 28.9% in the boars with potency disorders and 38.8% in those with no potency changes. Neither were there any significant differences in the E2 levels determined after HCG treatment between the boars with and without sexual potency disorders. It is inferred from the results that deviations in E2 concentration in the blood obviously do not contribute significantly to disorders in the sexual potency of boars.

[Androgenic aspects of estrogens]. / Nekteré andrologické aspekty estrogenu.

There is a literature review of the origin of oestrogens in male organisms, of the occurrence of oestrogens in the blood, urine and ejaculate of boars, of the importance of oestrogens in the endocrine regulation processes in males, and the role of oestrogens in relation to the sexual activity of males. It is emphasized that, as suggested by the latest findings, the exclusively antagonistic concept of the function of androgens and oestrogens is overcome, having given way to the aspect of synergism of these sex hormones and their physiological role in both sexes.

[Effect of exogenous administration of steroids during the 1st month of pregnancy in sows and gilts on certain characteristics of the litter]. / Ucinek exogenního prívodu steroidu v prvním mesíci gravidity prasnic a prasnicek na nekteré charakteristiky vrhu selat.

Four trials were performed to evaluate the influence of i. m. application of progesterone and estrogens to 444 experimental and control sows and gilts, kept mostly under large-scale production conditions, during the first month of pregnancy, as exerted on the number of born piglets, live born piglets and on the average birth weight of the live born piglet in litter. In the first trial the experimental sows and gilts on the 16th and 17th days of gravidity were applied 25 mg of progesterone (P4) and 12.5 micrograms of estrone (E1), in the second trial in the same phase of gravidity 25 mg of P4 with 1.25 micrograms of estradiol-17 beta (E2) and in the third trial in the identical gestation phase only 12.5 micrograms of E2 per head/day. In the fourth trial, experimental animals were given 0.55 mg of P4 with 0.275 micrograms of E1 per one kg of live weight, for six subsequent days between the 25th and 30th day of gravidity. In all trials the control animals were administered, under the same conditions, only the vehicle. None of the performed trials proved a significant difference in the studied parameters of litters of experimental and control animals (P greater than 0.05). The application of 25 mg of P4 with 1.25 micrograms of E2 on the 16th and 17th days of gravidity per sow/day under the conditions of small-scale production with the extension of the evaluated criteria of litter quality had no significant influence (P greater than 0.5) on the above-mentioned indicators, nor on the average birth weight of the whole litter and on the average number and weight of piglets of experimental sows at weaning. These results document that the verified application of hormonal substances in the above-mentioned phases of the first month of sow and gilt gravidity do not represent, in view of the intensive reproduction of pigs, a suitable procedure.

[The effect of the microclimate in the insemination facility on conception in sows after the first insemination]. / Vliv mikroklimatu inseminacní haly na zabrezávání prasnic po první inseminaci.

In the course of the year, the temperature and relative humidity of the insemination hall of a large pig farm were studied in ten three-week periods. The results were compared with the conception rate of sows inseminated in these periods. The macroclimatic conditions were also studied, and the influence of macroclimate (including temperature and relative humidity) on the microclimate of insemination hall was evaluated. The studied microclimate parameters were found to influence the conception of sows in the first three weeks after insemination. Highly significant differences (significance level of alpha = 0.01) were recorded in the conception of sows after the first insemination, in the occurrence of optimum and increased temperatures, in the occurrence of optimum and increased relative humidity in the summer and winter months. A significant difference at the significance level of alpha = 0.05 was found when the occurrence of increased relative humidity was compared. A high temperature was recorded only in the summer months. In summer and in the first half of autumn (from the 9th of June to the 13th of October) when increased to high temperatures and increased to high relative humidity prevailed in the insemination hall (optimum temperature only in 2.0 to 23.3% of the period; optimum relative humidity in 11.1 to 50.0% of the period), the sow conception rate after the first insemination was low (45.5 to 49.7%). In autumn the microclimatic conditions in the insemination hall returned to the optimum. From the 4th of November to the 16th of February the optimum temperature (optimum in 71.6 to 89.7% of the period) and optimum relative humidity (optimum in 74.2 to 90.7% of the period) prevailed in the insemination hall, enabling an improvement in the conception of sows after the first insemination (71.4 to 80.1%). The temperature inside the insemination hall was influenced by changes in outside temperatures whereas the relative humidity inside the insemination hall was influenced mainly by internal factors.

[Intratesticular administration of testosterone in the therapy of disorders of the quality of ejaculates in boars]. / Intratestikulární aplikace testosteronu v terapii poruch kvality ejakulátu u kancu.

The clinical effect of the bilateral intratesticular administration of a microcrystalline water suspension of testosterone was studied in ten boars of Duroc breed exhibiting semen quality disorders. The ejaculate quality disorders included separate or combined deviations of the values of sperm concentration (hypozoospermia to oligozoospermia), sperm activity (asthenozoospermia), or the occurrence of abnormal spermatozoa (teratozoospermia) from the spermiological standard. After intratesticular infiltration, all the criteria of spermiogram were completely restored in four cases and the boars could be returned to insemination use. A partial improvement of the spermiogram (the number of spermiological criteria with positive responses and the development of their values) without fully meeting all the requirements of the spermiological standard was recorded in four breeding boars. No positive response of ejaculate quality characteristics was obtained in two boars. As to the evaluated criteria of the spermiogram, sperm activity was the most frequent positively influenced parameter in the cases of idiopathic or combined asthenozoospermia, and the increased percentage of abnormal spermatozoa was the least frequent positively influenced parameter in the cases of idiopathic or combined teratozoospermia. It is supposed that the easily practicable methods of intratesticular infiltration with a microcrystalline testosterone suspension could expand the therapeutic possibilities available to veterinary andrologists in the treatment of ejaculate quality disorders in boars.

[Relation between aspartate aminotransferase (AST) activity in the seminal fluid and indicators of boar ejaculate quality]. / Vztah mezi aktivitou aspartát aminotransferázy (AST) v seminální plazme a nekterými ukazateli kvality ejakulátu kancu.

In a set of 154, and/or 260 ejaculates, collected from 72 boars, a relationship was studied between the activity of aspartate aminotransferase (AST) in seminal plasma and sperm concentration, and/or percent occurrence of morphologically abnormal spermatozoa. We failed to demonstrate any relation between the AST activity and sperm concentration (r = 0.023; P greater than 0.05). However, a statistically significant relation (P less than or equal to 0.05) was demonstrated between the AST activity and percent occurrence of morphologically abnormal spermatozoa (r = 0.343). Applying the above results and in agreement with literary data, determination of AST activity in the seminal plasma of boars can be considered as an important indicator of the cellular damage of sperms.

[Changes in selected biochemical indicators in blood serum in anestrous gilts]. / Zmeny vybraných biochemických ukazatelu krevního séra u anestrických prasnicek.

The biochemical profile [levels of calcium, phosphorus, magnesium, chlorides and iron, the activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and the concentrations of total protein, albumin, cholesterol, urea, glucose, and vitamins A and E] was studied in the blood serum of 40 anoestrous and 40 control inseminated animals in a production herd with an increased occurrence of anoestrus in gilts. The anoestrous gilts showed significantly lower levels of albumin (P less than 0.01) and glucose (P less than 0.01) and ALP activity (P less than 0.05), and significantly higher concentrations of urea (P less than 0.01), vitamin A (P less than 0.01) and vitamin E (P less than 0.05) and ALT activity (P less than 0.05), as compared with the inseminated controls. An extended enzymatological examination consisting of the evaluation of the activities of ALP, AST, ALT and gamma-glutamyl transferase (GMT) was performed in another set of 22 anoestrous and 20 mated gilts. The anoestrous gilts showed a statistically significant increase in the activities of AST (P less than 0.01), GMT (P less than 0.01) and ALT (P less than 0.05) and an insignificant increase in the activity of ALP in comparison with the control animals. The comparison of the obtained values of the studied biochemical criteria with literary data indicated a lower concentration of magnesium and a higher ALP and ALT activities in the anoestrous and inseminated gilts in both groups under study. A high acidity of fat and a medium to high fungus infestation (Mucor sp., Aspergillus sp.) were found by chemical and mycological examination of the administered feed mixtures. The histological examination of the ovaries of anoestrous animals showed cystically degenerative changes, proliferations of fibrous elements, and partial atrophy of ovarial cortex. It has been inferred from the observations that mycotoxins may be involved in the increase in the occurrence of anoestrus, either by a direct effect on sexual organs or by impairing the function of liver which, secondarily contributes to the rise of ovarial dysfunctions.

[Biochemical parameters of blood sera from clinically healthy boars of the Large White, Landrace and Duroc breeds]. / Biochemické ukazatele krevního séra klinicky zdravých kancu plemene bílé uslechtilé, Landrase a Duroc.

The levels of eleven biochemical parameters were determined in the blood serum of 150 healthy breeding boars of the Large White, Landrace and Duroc breeds from three A. I. stations. The following average values were obtained: calcium 1.94 +/- 0.42 mmol . l-1 with a statistically significant difference of the means between the LW and L breeds, phosphorus 1.87 +/- 0.31 mmol . l-1 with a statistically significant difference of the means between the LW and L breeds, magnesium 0.61 +/- 0.12 mmol . l-1 with a statistically significant difference of the means between the LW and D breeds, iron 25.98 +/- 5.41 micron mol . l-1 without statistically significant inter-breed differences, chlorides 97.75 +/- 7.04 mmol . l-1 without statistically significant inter-breed differences, alkaline phosphatase 55.97 +/- 24.72 U . l-1 without statistically significant inter-breed differences, transaminase GOT 14.96 +/- 4.86 U . l-1 with statistically significant differences of the means in the D breed compared with LW and L, transaminase GPT 27.75 +/- 6.65 U . l-1 without statistically significant inter-breed differences, total protein 75.00 +/- 5.82 g . l-1 without statistically significant inter-breed differences, total protein 75.00 +/- 5.82 g . l-1 with a statistically significant difference between the LW and L breeds, creatinin 203.67 +/- 27.97 micron mol . l-1 with statistically significant differences of the means in the L breed compared with LW and D, and urea 5.55 +/- 1.22 mmol . l-1 with a statistically significant difference of the means between the LW and L breeds. It is recommended for clinical practice to respect inter-breed differences in parameters specially mentioned in discussion.

[Relationships between spermiological, biochemical, endocrinological and fertilizing characteristics of boar ejaculates]. / Vztahy mezi Nekterými spermiologickými, biochemickými, endokrinologickými a fertilizacními ukazateli kancích ejakulátu.

Ejaculate volume, sperm concentration, total number of abnormal spermatozoa, number of spermatozoa with protoplasmic droplet, and the content of chlorides, magnesium, calcium and testosterone in semen plasma were evaluated in 155 ejaculates obtained from 77 boars. Further, the evaluation included the fertilizing ability of the ejaculates, expressed by conception rate after the first insemination, average number of all piglets and live-born piglets in litter after inseminations with the studied semen. The following significant (P less than 0.01) relationships were found after the evaluation of the mutual correlations of the studied characteristics: ejaculate volume to sperm concentration (r = -0.496), chlorides to calcium (r = -0.240), chlorides to magnesium (r = -0.492), magnesium to calcium (r = +0.261), testosterone to conception rate after the first insemination (r = -0.222), boar age to ejaculate volume (r = +0.285), boar age to sperm concentration (r = -0.375), boar age to magnesium (r = -0.281), length of sexual rest to total percentage of abnormal spermatozoa (r = +0.323) and to the percentage of spermatozoa with protoplasmic droplet (r = +0.367). The importance of these findings is treated in discussion.

[Relations of certain indicators of ejaculate quality of breeding boars to seasonal changes in the microclimate in pigsties]. / Vztah nekterých ukazatelü kvality ejakulátu plemenných kancú k sezónním zmenám stájového mikroklimatu.

A yearlong evaluation of the semen volume, concentration and number of morphologically abnormal sperms of 1722 ejaculates from 53 boars of Large White, Duroc and Landrace breeds housed in one building was performed. Simultaneously, continuous registration of temperature and of the relative humidity of the sty climate was performed, and the cooling value and the air flow in the sty were determined. In the followed period also the conception rate of sows after the first insemination by semen of the studied set of boars was evaluated. In summer season, at the increased and high temperatures and the relative sty humidity and at the lower air flow, the lowest average volume of ejaculate, the highest average sperm concentration and the minimum average number of abnormal sperms were recorded. In winter season, from the microclimatic viewpoint characterized mainly by the optimum air temperature but by high relative humidity and by excessive air flow, the highest average ejaculate volume with a lower average sperm concentration and with a maximum occurrence of abnormal sperms was recorded. The parametric differences in ejaculate quality in summer and winter seasons were statistically significant, however, their variations did not exceed the spermiologic standard throughout the year. The found decrease in conception rate of sows after the first insemination by the semen of the followed set of breeding boars in warm months is obviously to be attributed to the sows or to the changes of other andrological criteria than those being subject of this study.

[The effect of LH releasing hormone on testosterone levels in the blood of boars with sexual dysfunctions]. / Ucinek aplikace LH-releasing hormonu na hladiny testosteronu v krvi kancu s poruchami sexuálních funkcí.

The levels were assessed of testosterone in the blood plasma before and 90 minutes after i.v. application of 1 mg of synthetic LH-releasing hormone to 57 boars with disorders of sexual functions and to 43 boars without sexual dysfunctions. The group of animals with sexual disorders included boars with inferior ejaculate quality and low fertility (24 animals) and cases with disturbed sexual potency (33 boars). In animals with the studied changes of sexual functions, compared with boars without sexual dysfunctions, no statistically significant difference was found in the basal concentration of testosterone in the blood. LH-releasing hormone application increased significantly the testosterone levels in the group of boars without sexual disorders by 99.5% on an average and in the whole group of animals with changes in sexual functions approximately by only 65.8%. At the same time in the subgroup of inferior ejaculate quality and low fertility the post-application increase of testicular incretion reached 60.4% and in potency disorders 61.6% and was statistically insignificant in the latter. On the basis of these findings it was derived that in boars with reproduction deviations there existed a decreased incretion reserve of the system hypophysis - testicle and the involvement of this factor in the formation of the studied sexual disorders is assumed. The obtained results are discussed in view of the earlier findings about the incretion reserve of the testicles in boars with changes in sexual functions.

[The effect of chorionic gonadotropin administration on testosterone levels in the blood of boars with sexual function disorders]. / Vliv aplikace choriového gonadotropinu na hladiny testosteronu v krvi kancü s poruchami sexuálních funkcí.

Thirty-three boars with sexual dysfunctions and twenty-six boars clinically sound as to their reproductive capacity were evaluated for the testosterone levels in the blood plasma before i.v. administration of 500 i.u. of chorionic gonadotropin and two hours after the administration. A group of animals with reproduction disorders comprised boars with an impaired quality of ejaculate and low fertility ability (18 boars) and with sexual dysfunctions (15 boars). No statistically significant difference in the basal concentration of testosterone in the blood was found in the boars with the studied sexual dysfunctions, as compared with the boars with no sexual dysfunctions. Administration of chorionic gonadotropin increased significantly the plasma testosterone levels in both groups. If the effect of chorionic gonadotropin on the studied level of this hormone was compared in boars with sexual dysfunctions and in boars without any disorders, no significant differences were proved. It has been inferred from the above findings that there are no significant disorders of androgen supply and incretion reserve of the gonads in the boars with sexual dysfunctions.