Praćenje rane gravidnosti i rane embrionalne smrtnosti primjenom ultrazvučne pretrage i određivanjem razine trofoblastičnoga proteina i progesterona u kravljem serumu

The aim of study was to investigate the role of pregnancy-associated glycoproteins (PAG) in early pregnancy, as well as the possibility of using PAG and ultrasound as diagnostic tools in the diagnosis of embryonic mortality. Our research included 73 Simmental cows, 3-7 years old, which calved every year. According to ultrasound findings (on the 17th, 24th, 35th and 45th day following AI), the cows were divided into 3 groups: pregnant cows (n = 34), non-pregnant cows (n = 18) and cows which had suffered embryonic mortality (n = 21). Blood samples were collected every 72 hours between the 12th and 45th day following AI and levels of progesterone and pregnancy-associated glycoproteins (PAG) were determined. Statistical analysis of variance for progesterone at days 12, 21 and 35 following AI showed significant differences between pregnant cows and both the non-pregnant and embryonic mortality groups (P>0.05). PAG variance analysis at days 24, 30 and 34 following AI showed highly significant differences (P>0.01) between the non-pregnant and both the embryonic mortality and pregnant groups. On the other hand, variance analysis showed that mean values for PAG at days 40 and 45 following AI were highly significantly different (P>0.01) between the pregnant and both the nonpregnant and embryonic mortality groups. The conclusion emerged that it is impossible to determine embryonic mortality merely on the basis of progesterone profile, but it is easy to distinguish pregnant from non-pregnant cows, supposing cows to be more than 21 days pregnant. It is very easy and accurate to distinguish non-pregnant cows from cows that have suffered early embryonic mortality. Furthermore, 98% of the cows in our research which had experienced embryonic mortality, lost their embryos 17-24 days after AI, visible in a drastic decrease in PAG seven and half to nine days later. Using PAG for pregnancy diagnosis enables us to prove the existence of live, vital embryos in utero 24 days after conception.Svrha ovog rada bila je istražiti ulogu trofoblastičnoga proteina (PAG) u fiziologiji rane gravidnosti u goveda kao i mogućnost njegove primjene te ultrazvuka u dijagnostici rane embrionalne smrtnosti. Promatrane su bile 73 krave simentalske pasmine, u dobi od tri do sedam godina, u kojih nisu ustanovljene poteškoće s plodnošću. Sve su držane na pet obiteljskih gospodarstava u Međimurskoj županiji, u uzgojima koji su brojili od osam do 20 krava. Krave su bile podijeljene u tri skupine: gravidne krave (n = 34), krave sumnjive na ranu embrionalnu smrtnost (n = 21) i negravidne krave (n = 18). Na osnovi ultrazvučnih pretraga i laboratorijskoga praćenja razine progesterona i trofoblastičnoga proteina u serumu od 12. do 45. dana nakon UO donijeti su sljedeći zaključci. Na osnovi razine progesterona u serumu moguće je razlučiti gravidne od negravidnih krava, ali nije moguće dijagnosticirati embrionalnu smrtnost. Na temelju razine trofoblastičnoga proteina moguće je sa sigurnošću razlikovati krave kod kojih je nastupila embrionalna smrtnost nakon 16. dana gravidnosti od krava koje nisu postale steone. Embrionalna smrtnost vidljiva je na osnovi znatnoga pada razine trofoblastičnoga proteina u serumu majke, i to 7,5-9 dana nakon uginuća embrija, koliko iznosi i biološki poluživot trofoblastičnoga proteina u prvom mjesecu gravidnosti. Praćenjem razine trofoblastičnoga proteina u serumu moguće je pouzdano dokazati postojanje živoga vitalnoga embrija u maternici steone krave već nakon 24. dana steonosti. U istraživanju je 98% krava u skupini u kojoj je nastupila embrionalna smrtnost izgubilo embrij kad su bile gravidne 17-24 dana što predstavlja kritično razdoblje za preživljavanje embrija

Ultrabrza vitrifikacija u otvorenoj rastegnutoj slamci otvara nove mogućnosti za smrzavanje konjskih zametaka.

The aim of this research was to evaluate ultra rapid OPS vitrification on the embryo viability. The OPS vitrification technique is comprised of ultra rapid freezing of a small drop in which the embryo is placed. Before the thin straw was plunged into the liquid nitrogen, the embryos were treated with highly concentrated cryoprotectant (CPA) solutions as follows: 18% ethylene glycol (EG), 18% dimethyl-sulfoxide (DMSO) and 0.4 M sucrose. Surgical transfer into the recipient mares and morphologic examination of recollected embryos were used to measure the viability of transferred embryos. The research was performed on Welsh pony mares by collecting the embryos 6.75 days after ovulation. Twenty embryos were vitrified and transferred, four in each recipient mare. At day twelve, nine embryos were recollected after fl ushing of the recipient uterus (56%, 9/ 16). In one recipient mare, endometritis was detected when the uterus was fl ushed. Among the sixteen recollected embryos, seven (44%) had normal morphology and well developed embryonic vesicles. The vitrification procedure used proved to be encouraging.Svrha istraživanju bila je ustanoviti učinkovitost ultrabrze vitrifikacije u otvorenoj rastegnutoj slamci na vitalnost konjskih zametaka, prijenosom vitrificiranih pa otopljenih zametaka u sinkronizirane primateljice. Istraživanje je provedeno na stadu Welsh poni kobila. Davateljicama zametaka maternice su transcervikalno bile ispirane 6,75 dana nakon ovulacije, a zametci su nakon vitrifikacije bili pohranjeni u spremnik s tekućim dušikom. Nakon odmrzavanja, zametci su bili prenijeti u sinkronizirane primateljice. Maternice primateljica bile su ispirane petoga dana nakon prijenosa odmrznutih zametaka. Ukupno je bilo preneseno dvadeset zametaka, a ispiranjem maternica primateljica dobiveno je devet zametaka što iznosi 56% s obzirom da je u jedne primateljice ispiranjem ustanovljen endometritis. Od zametaka dobivenih ispiranjem primateljica, sedam (44%) je imalo morfološki normalno razvijene zametne mjehure. Na osnovi provedenih istraživanja zaključeno je da su rezultati ostvareni vitrifikacijom u otvorenoj rastegnutoj slamci ohrabrujući, ali bi ih s obzirom na mali broj prenijetih zametaka trebalo potvrditi na većem uzorku, posebice sa zametcima odabranoga promjera te brojem ždrebadi

Uporaba hipoosmotskog testa i supravitalnog bojenja za ocjenu kakvoće nerastova sjemena.

Semen samples from ten boars, Yorkshire and Pietrain breed, aged between two and six years were used. The sperm quality was evaluated using the following parameters: the motility (subjective), the structural supravital staining (eosine/nigrosine) and the functional integrity of sperm membrane (HOS test). The majority of HOS reactive or swelled up spermatozoa were gained in a hypoosmolar solution of 100 mOsm/kg by incubation of 30 minutes. Between middle values for HOS reactive (swollen up) spermatozoa in hypoosmolar solutions with different osmolarity, significant differences (P<0.05) were determined. Using a hypoosmotic solution with different osmolarity 100 mOsm/kg, significantly strong, positive correlations between HOS and motility (r = 0.98; P<0.05) were determined, between HOS test and supravital staining eosine/nigrosine (r = 0.99; P<0.05) and between motility and supravital staining eosine/nigrosine (r = 0.98; P<0.05). The results of our research have shown that the HOS test and supravital staining eosine/nigrosine could be used for routine evaluation of the functional and structural integrity of diluted boar sperm.U istraživanju su rabljeni ejakulati deset nerasta Yorkshir i Pietren pasmine, u dobi od dvije do šest godina koji su imali nizak indeks oplodnje. Kakvoća sperme ocjenjivana je na osnovi pokretljivosti (subjektivno) te strukturnog i funkcionalnog integriteta membrane spermija (supravitalno bojenje eozin/nigrozinom i HOS testom). Najveći broj HOS reaktivnih, tj. nabubrenih spermija ustanovljen je u hipoosmotskoj otopini od 100 mOsm/kg pri inkubaciji od 30 minuta. Između srednjih vrijednosti HOS reaktivnih (nabubrenih) spermija u hipoosmotskim otopinama različitih osmolarnosti ustanovljene su značajne razlike (P<0,05). Korištenjem hipoosmotske otopine osmolarnosti 100 mOsm/kg, ustanovljene su značajne, vrlo jake, pozitivne korelacije između HOS testa i progresivne pokretljivosti (r = 0.98; P<0,05), zatim između HOS testa i supravitalnog bojenja eozin/nigrozinom (r = 0,99; P<0,05), te između progresivne pokretljivosti i supravitalnog bojenja eozin/nigrozinom (r = 0,98; P<0,05). Rezultati ovog istraživanja pokazali su da su HOS test i supravitalno bojenje eozin/nigrozinom jednostavne metode koje se mogu rutinski primjenjivati za ocjenu funkcionalnog i strukturnog integriteta sperme nerasta

Koštana alkalna fosfataza, osteokalcin i C-terminalni telopeptid kao pokazatelji koštane pregradnje u kuja

In clinical veterinary practice the measurement of biochemical markers for assessment of bone metabolism is not yet fully established and is only being used for now as a scientifi c method in investigations. The purpose of this research is the better understanding of bone metabolism in dogs and assessing the possible utility of biochemical bone markers in routine clinical veterinary practice. The bone markers selected for this study were: bone alkaline phosphatase and osteocalcin as indicators of bone formation, and C-terminal telopeptide of type I collagen as marker of bone resorption. The research was conducted on 58 canine bitches of different breeds. The results indicate increased bone turnover in young animals and decreased turnover in old ones since the highest activities of the investigated bone markers were in the youngest group and they then declined with age. However, elevated activity of bone alkaline phosphatase was noted in older bitches, which has not been detected in other animal species or in healthy humans. Higher bone resorption and lower formation were noticed in heavier dogs.U veterinarskoj medicini saznanja o biokemijskim pokazateljima koštane pregradnje oskudna su i nedostatna, a njihova primjena je za sada isključivo istraživačka. Cilj ovog istraživanja bio je bolje poznavanje koštanoga metabolizma u pasa na temelju mjerenja biokemijskih pokazatelja koštane pregradnje u krvi te procjena moguće kliničke primjene tih pokazatelja u rutinskoj veterinarskoj kliničkoj praksi. Pokazatelji koštane pregradnje koji su upotrijebljeni u ovom istraživanju jesu: koštana alkalna fosfataza i osteokalcin, kao pokazatelji izgradnje i C-terminalni telopeptid kao pokazatelj razgradnje kosti. Istraživanje je provedeno na 58 kuja različitih pasmina. Rezultati pokazuju pojačanu pregradnju kostiju u mladih životinja i smanjenu u starih životinja budući da su najviše vrijednosti koštanih pokazatelja utvrđene u mladih životinja, te su opadale s dobi. Međutim, povećana aktivnost koštane alkalne fosfataze zabilježena je u starijih kuja, što nije zapaženo u ostalih životinjskih vrsta niti zdravih ljudi. Također je uočena povećana razgradnja i smanjena izgradnja kosti u pasa veće tjelesne mase

Koštana alkalna fosfataza, osteokalcin i C-terminalni telopeptid kao pokazatelji koštane pregradnje u kuja

In clinical veterinary practice the measurement of biochemical markers for assessment of bone metabolism is not yet fully established and is only being used for now as a scientifi c method in investigations. The purpose of this research is the better understanding of bone metabolism in dogs and assessing the possible utility of biochemical bone markers in routine clinical veterinary practice. The bone markers selected for this study were: bone alkaline phosphatase and osteocalcin as indicators of bone formation, and C-terminal telopeptide of type I collagen as marker of bone resorption. The research was conducted on 58 canine bitches of different breeds. The results indicate increased bone turnover in young animals and decreased turnover in old ones since the highest activities of the investigated bone markers were in the youngest group and they then declined with age. However, elevated activity of bone alkaline phosphatase was noted in older bitches, which has not been detected in other animal species or in healthy humans. Higher bone resorption and lower formation were noticed in heavier dogs.U veterinarskoj medicini saznanja o biokemijskim pokazateljima koštane pregradnje oskudna su i nedostatna, a njihova primjena je za sada isključivo istraživačka. Cilj ovog istraživanja bio je bolje poznavanje koštanoga metabolizma u pasa na temelju mjerenja biokemijskih pokazatelja koštane pregradnje u krvi te procjena moguće kliničke primjene tih pokazatelja u rutinskoj veterinarskoj kliničkoj praksi. Pokazatelji koštane pregradnje koji su upotrijebljeni u ovom istraživanju jesu: koštana alkalna fosfataza i osteokalcin, kao pokazatelji izgradnje i C-terminalni telopeptid kao pokazatelj razgradnje kosti. Istraživanje je provedeno na 58 kuja različitih pasmina. Rezultati pokazuju pojačanu pregradnju kostiju u mladih životinja i smanjenu u starih životinja budući da su najviše vrijednosti koštanih pokazatelja utvrđene u mladih životinja, te su opadale s dobi. Međutim, povećana aktivnost koštane alkalne fosfataze zabilježena je u starijih kuja, što nije zapaženo u ostalih životinjskih vrsta niti zdravih ljudi. Također je uočena povećana razgradnja i smanjena izgradnja kosti u pasa veće tjelesne mase

Ultrazvučno praćenje odgovora jajnika na program multiple ovulacije i embriotransfera u koza.

The aim of this research was to establish the importance and accuracy of ultrasonic examination of goats in order to estimate the superovulatory response. For this reason, 28 donor goats were systematically examined by real time ultrasonography to count the preovulatory follicles at observed oestrus onset and to confirm respective ovulation(s) 48 h later. The accuracy of ultrasound exams was analysed comparing the number of preovulatory follicles with number of corpora lutea (CL′s) counted during embryo collection. The total relative undervalue of ultrasound prediction of multiple ovulation was found to be 19.4%. In all ovaries examined, the total number of preovulatory follicles minus number of unovulated follicles was lower than the number of CL′s. The relationship between the predicted ovulation rate and number of CL’s was positive and significant (CL 3.98 + 0.75 follicle; r2 0.93), with significantly higher intercept (1.45) for the right ovary. Also, the accuracy of ultrasound to establish the ovulating and non-ovulating goats was 100.0%. However, determination of the exact number of multiple ovulations on ovaries was 45.0%. In conclusion, the ultrasonography of donor goats is an useful tool to monitor follicular dynamics and success of superovulation procedures. Counting the number of follicles >4 mm in diameter at the oestrus onset and confirming the ovulation is a good method for selection of responding goats prior to flushing of uterus.Cilj ovog istraživanja bio je ustanoviti važnost i točnost ultrazvučnog pregleda koza u procjeni uspješnosti postupka superovulacije. U tu svrhu je 28 koza davateljica bilo sustavno pregledavano „real-time“ ultrazvučnom metodom kako bi se izbrojali preovulacijski folikuli na početku estrusa i potvrdile ovulacije 48 sati kasnije. Provjerena je točnost ultrazvučnih nalaza i uspoređena s brojem žutih tijela utvrđenih prilikom ispiranja maternice. Ukupna relativna podcijenjenost ultrazvučnog predviđanja multiple ovulacije iznosila je 19,4%. Na svim pregledanim jajnicima, ukupni broj preovulacijskih folikula umanjen za broj neovuliranih folikula bio je manji nego broj žutih tijela. Odnos između predviđene stope ovulacije i broja žutih tijela bio je pozitivan i značajan (CL 3,98 + 0,75 folikula; r2 0,93), sa značajno višim interceptom (1,45) za desni jajnik. Također, točnost utvrđivanja ovulirajućih i neovulirajućih koza ultrazvukom iznosila je 100,0%. Međutim, određivanje točnog broja multiplih ovulacija na jajnicima bilo je na razini od 45,0%. Iz navedenog se može zaključiti kako je ultrazvučno pregledavanje koza davateljica korisna metoda za praćenje folikularne dinamike i uspjeha superovulacije. Brojenje folikula promjera >4 mm na početku estrusa i potvrda ovulacije je dobra metoda za odabir koza koje su dobro reagirale na superovulacijske postupke prije ispiranja maternice

Unilateralna segmentalna aplazija materničnoga roga gravidne kuje - prikaz slučaja

A 1.5-year-old mongrel bitch was presented at the Clinic for obstetrics and reproduction at the Faculty of Veterinary Medicine in Zagreb for spaying. Since the animal had been found and kept in animal shelter, no anamnestic data about her reproductive status were known. A general examination did not reveal any preoperative problem. On ultrasonograph it was found that bitch was about four weeks pregnant. Finally, and with the owner’s consent, ovariohysterectomy was proposed and accepted as a radical alternative to medical abortion following an unwanted pregnancy, as it also involves defi nitive sterilization. The surgical procedure comprising ovariohisterectomy was performed under general endotracheal anesthesia. The procedure revealed segmental aplasia of the left uterine horn with an intact left ovary and kidney.Na Kliniku za porodništvo i reprodukciju Veterinarskog fakulteta Sveučilišta u Zagrebu dovedena je kuja miješane pasmine stara 1,5 godinu na kastraciju. Anamnestički podatci o reproduktivnom statusu nisu bili poznati s obzirom na to da je kuja došla iz prihvatilišta za napuštene životinje. Općim kliničkim pregledom nije utvrđen nikakav preoperativni problem. Ultrazvučnim pregledom ustanovljeno je da je kuja gravidna oko četiri tjedna. Vlasniku je predložena ovariohisterektomija kao radikalna alternativa pobačaju zbog neželjene gravidnosti. Operacija je uz pristanak vlasnika izvedena u općoj endotrahealnoj anesteziji. Prilikom izvođenja zahvata utvrđena je ageneza lijevoga materničnoga roga dok su lijevi jajnik i bubreg bili normalno razvijeni

Praćenje razine kortizola u slini mliječnih koza u travnju, svibnju i srpnju u poluintenzivnom sustavu držanja

The aim of the current study was to evaluate the level of saliva cortisol and heart rate in lactating goats depending on different environmental condition, from early spring to the summer heat in the mountainous region of Croatia with a moderate climate zone (average winter air temperature from -2°C to -4°C and summer below 20°C). Ten lactating goats (6 Saanen and 4 Alpine) kept confined, occasionally tethered, were included in the study. The barn was wooden, thermally insulated, divided into five equal pens divided by wooden partitions. Each pen housed two goats on deep hay bedding and ensuring sufficient space allowance per animal. Saliva sampling was carried out in early April when goats were kept exclusively in the barn and occasionally tethered, at the end of May when they spent part of the day grazing freely, and the end of July when they spent only the night in barn. Saliva samples of saliva were taken at 11 a.m. using special equipment and frozen until analysis, and heart rate was determined by palpation of a. femoralis. Samples were analysed by the enzyme immunoassay (EIA). Following statistical analysis of the results, no statistically significant differences in cortisol levels and heart rate were observed during the sampling period. Since the hypothalamus- pituitary-adrenal gland is extremely susceptible to environmental changes, cortisol level is considered to be a credible indicator of the ability of animals to adapt to changing environmental conditions. Based on the obtained results, it is possible to conclude that the investigated goats were kept in conditions and in a way that was not stressful to them and are almost ideal for achieving their optimal production performance, and goats adapted very well to the environmental changes during different seasons.Cilj ovog istraživanja bio je procijeniti razinu kortizola u slini mliječnih koza te vrijednosti b la ovisno o različitim uvjetima držanja, od ranog proljeća do vrhunca ljetnih vrućina u unutrašnjem planinskom području Hrvatske s umjerenom kontinentalnom klimom (zimi se prosječne temperature zraka kreću od -2 °C do -4 °C, a ljeti ispod 20 °C). Istraživanjem je bilo obuhvaćeno deset mliječnih koza u laktaciji (6 sanskih i 4 alpskih) koje su cijelu zimu provele zatvorene u oboru i povremeno na vezu. Obor je bio drveni, toplinski izoliran, podijeljen drvenom pregradom u 5 jednakih odjeljaka. U svakom su odjeljku bile smještene po dvije koze na dubokoj stelji od sijena i na površini više no dostatnoj po grlu. Uzorkovanje sline i utvrđivanje vrijednosti b la provodilo se početkom travnja kada su koze držane isključivo u zatvorenom i povremeno na vezu, krajem svibnja kada su dio dana provodile slobodne na ispaši i krajem srpnja kada su u oboru jedino provodile noć. Uzorci sline korištenjem posebnog pribora uzimani su ujutro u 11 sati, i smrznuti do izvođenja pretrage. Vrijednosti b la utvrđivane su palpacijom a. femoralis. Uzorci sline analizirani su imunoenzimnim postupkom (EIA). Nakon statističke obrade rezultata utvrđeno je da nema statistički značajne razlike u razini kortizola i vrijednosti b la tijekom različitih mjeseci uzorkovanja. S obzirom da je os hipotalamus-hipofiza-nadbubrežna žlijezda iznimno osjetljiva na promjene u okolišu, razina kortizola uzima se kao vjerodostojan pokazatelj sposobnosti prilagodbe životinje na promijenjene okolišne uvjete. Na temelju dobivenih rezultata moguće je zaključiti da su istraživane koze držane u uvjetima i na način koji za njih ne predstavljaju stres te su gotovo savršeni za postizanje njihova optimalnog proizvodnog potencijala, kao i da su se na promjene u okolišu tijekom različitih godišnjih doba vrlo dobro prilagođavale

Survival prediction of high-risk outborn neonates with congenital diaphragmatic hernia from capillary blood gases

BACKGROUND: The extent of lung hypoplasia in neonates with congenital diaphragmatic hernia (CDH) can be assessed from gas exchange. We examined the role of preductal capillary blood gases in prognosticating outcome in patients with CDH. ----- METHODS: We retrospectively reviewed demographic data, disease characteristics, and preductal capillary blood gases on admission and within 24 h following admission for 44 high-risk outborn neonates. All neonates were intubated after delivery due to acute respiratory distress, and were emergently transferred via ground ambulance to our unit between 1/2000 and 12/2014. The main outcome measure was survival to hospital discharge and explanatory variables of interest were preductal capillary blood gases obtained on admission and during the first 24 h following admission. ----- RESULTS: Higher ratio of preductal partial pressure of oxygen to fraction of inspired oxygen (PcO2/FIO2) on admission predicted survival (AUC = 0.69, P = 0.04). However, some neonates substantially improve PcO2/FIO2 following initiation of treatment. Among neonates who survived at least 24 h, the highest preductal PcO2/FIO2 achieved in the initial 24 h was the strongest predictor of survival (AUC = 0.87, P = 0.002). Nonsurvivors had a mean admission preductal PcCO2 higher than survivors (91 ± 31 vs. 70 ± 25 mmHg, P = 0.02), and their PcCO2 remained high during the first 24 h of treatment. ----- CONCLUSION: The inability to achieve adequate gas exchange within 24 h of initiation of intensive care treatment is an ominous sign in high-risk outborn neonates with CDH. We suggest that improvement of oxygenation during the first 24 h, along with other relevant clinical signs, should be used when making decisions regarding treatment options in these critically ill neonates

Praćenje razine kortizola u slini mliječnih koza u travnju, svibnju i srpnju u poluintenzivnom sustavu držanja

The aim of the current study was to evaluate the level of saliva cortisol and heart rate in lactating goats depending on different environmental condition, from early spring to the summer heat in the mountainous region of Croatia with a moderate climate zone (average winter air temperature from -2°C to -4°C and summer below 20°C). Ten lactating goats (6 Saanen and 4 Alpine) kept confined, occasionally tethered, were included in the study. The barn was wooden, thermally insulated, divided into five equal pens divided by wooden partitions. Each pen housed two goats on deep hay bedding and ensuring sufficient space allowance per animal. Saliva sampling was carried out in early April when goats were kept exclusively in the barn and occasionally tethered, at the end of May when they spent part of the day grazing freely, and the end of July when they spent only the night in barn. Saliva samples of saliva were taken at 11 a.m. using special equipment and frozen until analysis, and heart rate was determined by palpation of a. femoralis. Samples were analysed by the enzyme immunoassay (EIA). Following statistical analysis of the results, no statistically significant differences in cortisol levels and heart rate were observed during the sampling period. Since the hypothalamus- pituitary-adrenal gland is extremely susceptible to environmental changes, cortisol level is considered to be a credible indicator of the ability of animals to adapt to changing environmental conditions. Based on the obtained results, it is possible to conclude that the investigated goats were kept in conditions and in a way that was not stressful to them and are almost ideal for achieving their optimal production performance, and goats adapted very well to the environmental changes during different seasons.Cilj ovog istraživanja bio je procijeniti razinu kortizola u slini mliječnih koza te vrijednosti b la ovisno o različitim uvjetima držanja, od ranog proljeća do vrhunca ljetnih vrućina u unutrašnjem planinskom području Hrvatske s umjerenom kontinentalnom klimom (zimi se prosječne temperature zraka kreću od -2 °C do -4 °C, a ljeti ispod 20 °C). Istraživanjem je bilo obuhvaćeno deset mliječnih koza u laktaciji (6 sanskih i 4 alpskih) koje su cijelu zimu provele zatvorene u oboru i povremeno na vezu. Obor je bio drveni, toplinski izoliran, podijeljen drvenom pregradom u 5 jednakih odjeljaka. U svakom su odjeljku bile smještene po dvije koze na dubokoj stelji od sijena i na površini više no dostatnoj po grlu. Uzorkovanje sline i utvrđivanje vrijednosti b la provodilo se početkom travnja kada su koze držane isključivo u zatvorenom i povremeno na vezu, krajem svibnja kada su dio dana provodile slobodne na ispaši i krajem srpnja kada su u oboru jedino provodile noć. Uzorci sline korištenjem posebnog pribora uzimani su ujutro u 11 sati, i smrznuti do izvođenja pretrage. Vrijednosti b la utvrđivane su palpacijom a. femoralis. Uzorci sline analizirani su imunoenzimnim postupkom (EIA). Nakon statističke obrade rezultata utvrđeno je da nema statistički značajne razlike u razini kortizola i vrijednosti b la tijekom različitih mjeseci uzorkovanja. S obzirom da je os hipotalamus-hipofiza-nadbubrežna žlijezda iznimno osjetljiva na promjene u okolišu, razina kortizola uzima se kao vjerodostojan pokazatelj sposobnosti prilagodbe životinje na promijenjene okolišne uvjete. Na temelju dobivenih rezultata moguće je zaključiti da su istraživane koze držane u uvjetima i na način koji za njih ne predstavljaju stres te su gotovo savršeni za postizanje njihova optimalnog proizvodnog potencijala, kao i da su se na promjene u okolišu tijekom različitih godišnjih doba vrlo dobro prilagođavale