Anthelmintic Efficacy of Selected Essential Oils against Gastrointestinal Nematodes of Sheep

Gastrointestinalne nematode (GIN) u današnje vreme predstavljaju jednog od najvećih zdravstvenih i ekonomskih problema kod malih preživara. Kontrola ovih parazita se uglavnom zasniva na primeni komercijalnih preparata. Međutim, njihova neracionalna upotreba u smislu učestalih tretmana, niskih ili visokih doza ili kontinuirane upotrebe jednog leka je dovela do razvoja antihelmintičke rezistencije (AR). Savremene strategije borbe protiv AR podrazumevaju racionalnu upotrebu ovih lekova, uz korišćenje različitih alternativa poput botaničkih antihelmintika. Ciljevi ovih istraživanja su bili ispitati antihelmintičku aktivnost odabranih etarskih ulja (EOs) protiv GIN ovaca i sigurnost njihove primene, odrediti faktore koji utiču aktivnost, kao i oceniti mogućnost primene ispitivanih formulacija u veterinarskoj praksi kao alternativne metode u borbi protiv AR. Ispitivanje je vršeno u dve faze (istraživanja), tokom 2019. i 2021. godine, pri čemu je u prvom ispitano 12 uzoraka ulja a u drugom11 (od čega su tri ista kao i u prethodnoj fazi, odnosno dva od istog proizvođača, jedno od drugog). Hemijski sastav ulja je određen pomoću gasne hromatografije i masene spektrometrije (GC-MS analize). In vitro ovicidna aktivnost je ispitana uz pomoć testa izleganja larvi (eng. egg hatch test, EHT), u prvom istraživanju pri šest različitih koncentracija za svako ispitano ulje (50, 12,5, 3,125, 0,781, 0,195 i 0,049 mg/ml), a u drugom su pored navedenih dodate još dve niže koncentracije (0,025 i 0,0125 mg/ml). Za prvo in vivo istraživanje su odabrani ulje timijana (tip 1) i sinergistička kombinacija linalool:estragol, a za drugo ulje origana, pitome nane i rtanjskog čaja. Efikasnost ulja je ispitana uz pomoć testa redukcije broja jaja u fecesu (eng. faecal egg count reduction test, FECRT), pri čemu su EOs razblažena u suncokretovom ulju a formulacije aplikovane jednokratno, peroralno životinjama u različitim grupama, u prvom istraživanju pri dozi od 100 mg/kg, a u drugom 150 mg/kg. Toksični efekti in vivo primenjenih formulacija su ispitani putem kliničkog pregleda testiranih životinja, a u drugom istraživanju i analizom hematoloških i biohemijskih parametara krvi u cilju procene efekata na krvnu sliku, funkciju jetre i bubrega. Za oglede su korišćene dve farme u južnoj Italiji, gde je u oba istraživanja putem koprokulture određeno prisustvo GIN kod ovaca, a prisutni rodovi identifikovani uz pomoć odgovarajućih ključeva determinacije. Rezultati GC-MS analiza su pokazali složen hemijski sastav testiranih etarskih ulja sa jedinjenjima čiji se broj kretao od 10-35, i koja pripadaju različitim hemijskim grupama (terpeni, terpenoidi i fenilpropanoidna jedinjenja). Najvišu ovicidnu aktivnost na EHT su u prvom istraživanju pokazala ulja origana, rtanjskog čaja i morača sa maksimalnim inhibitornim efektom na izleganje larvi (100%) pri svim testiranim koncentracijama, a pored njih i čubar (99,3-100%), oba uzorka timijana (timijan 1, 95,3-100% i timijan 2, 98,5-100%), kleka (81-96,8%) i pitoma nana (72,5-99,8%). U drugom istraživanju je zbog nešto drugačije pripreme koncentracija (metodom razblaživanja) efekat bio znatno više dozno-zavistan, ali je ulje origana bilo ponovo najefikasnije (71,3-93,3%), a potom miloduh (42,7-91,3%), korijander (29-92,7%), bosiljak (23,3-93,3%), pitoma (20-90,3%) i divlja nana (13-92,7%). Kada je u pitanju FECRT, u prvom istraživanju postignut je određen antihelmintički efekat sa ukupnom redukcijom broja jaja nematoda od 25,23% i 24,42% (timijan) i 24,91% i 25,90% (linalool:estragol), ali je efekat bio bolji kod ulja iz drugog istraživanja s obzirom na aplikaciju formulacija direktno u rumen životinja, odnosno 43,21% i 60,13% (origano), 26,86 i 46,04% (pitoma nana) i 15,66% i 33,00% (rtanjski čaj), 7. i 14. dana nakon tretmana. Ni za jedno od primenjenih ulja, pri testiranim dozama, nisu zabeleženi nikakvi neželjeni ili toksični efekti prilikom kliničkog pregleda odnosno hematoloških i biohemijskih analiza krvi, što govori u prilog bezbednosti njihove upotrebe kod ovaca. Pokazana efikasnost ispitanih ulja potiče od jedinjenja koja ulaze u njihov sastav, odnosno pre svih karvakrola, anetola, timola, p-cimena, γ-terpinena, karvona, linaloola, mentola, α-tujona i cis-pinokamfona, imajući u vidu njihovu zastupljenost kod najefikasnijih ulja. Koprokulturom je pri tome na ispitivanim farmama u oba istraživanja identifikovano prisustvo četiri roda GIN ovaca, Haemonchus, Trichostrongylus, Teladorsagia i Chabertia, čija se procentualna zastupljenost u određenoj meri menjala nakon tretmana. Primena biljnih formulacija uključujući EOs u cilju kontrole parazita ima više prednosti. To uključuje složen hemijski sastav sa bioaktivnim supstancama iz različitih hemijskihgrupa, koji dovodi do njihove visoke antihelmintičke aktivnosti, kao i potencijalno nižeg stepena razvoja rezistencije. Tehnike inkapsulacije ili višestruka primena tokom nekoliko uzastopnih dana pri tome nude mogućnost dodatnog povećanja efikasnosti u terenskim uslovima. Sa druge strane, prirodno poreklo ovih formulacija može doprineti i njihovoj nižoj toksičnosti za životinje, manjim količinama rezidua u mesu i mleku i boljoj ekološkoj prihvatljivosti u poređenju sa komercijalnim preparatima. U svakom slučaju, dobijeni rezultati govore u prilog mogućnosti korišćenja ispitanih EOs u praksi, posebno origana, u integrisanom pristupu kontrole u cilju smanjenja upotrebe komercijalnih preparata i usporavanja razvoja rezistencije.Gastrointestinal nematodes (GINs) nowadays represent one of the biggest health and economic issues in small ruminants. The control of these parasites is almost exclusively based on the application of commercial drugs. However, their irrational use in terms of frequent treatments, low or high doses or continuous use of one drug has led to the development of anthelmintic resistance (AR). Modern strategies for combating AR are based on the rational use of these drugs, along with the use of various alternatives such as botanical anthelmintics. The aims of these studies were to examine the anthelmintic activity of selected essential oils (EOs) against sheep GINs and the safety of their application, to determine the factors that influence the activity, as well as to evaluate the possibility of applying examined formulations in veterinary practice as an alternative method in combatting AR. The research was conducted in two phases (studies), in 2019. and 2021., whereby 12 oil samples were examined in the first and 11 in the second study (of which three are the same as in the previous study, two from the same manufacturer and one from the other). The chemical composition of the oils was determined by gaschromatography and mass spectrometry (GC-MS analysis). In vitro ovicidal activity was tested using the egg hatch test (EHT), in the first instance at six different concentrations for each tested oil (50, 12.5, 3.125, 0.781, 0.195 and 0.049 mg/ml), and in the second, in addition to the above, two lower concentrations (0.025 and 0.0125 mg/ml) were added. Thyme oil (type 1) and the synergistic combination of linalool:estragole in the first, and the oils of oregano, mint and winter savory in the second study were selected for further in vivo testing. The efficacy was tested using the faecal egg count reduction test (FECRT), whereby the EOs were diluted in sunflower oil and the formulations were applied once, perorally to animals in different groups, in the first case at a dose of 100 mg/kg and in the second at 150 mg/kg. The toxic effects of the in vivo applied formulations were examined through clinical observation of the tested animals, and in the second study also by analyzing the haematological and biochemical blood parameters in order to assess the side effects on the blood count, liver and kidney function. Two farms in southern Italy were used for the experiments, whereby the presence of GINs was determined by coproculture examination, and the present genera were identified with suggested determination keys. The results of GC-MS analyses showed the complex chemical composition of the tested EOs with the number of compounds varying from 10-35, which belong to different chemical groups (terpenes, terpenoids and phenylpropanoid compounds). The highest ovicidal effect in the first EHT was shown by the oils of oregano, winter savory and fennel with the maximum inhibitory effect on the egg hatchability (100%), along with summer savory (99.3-100%), both samples of thyme (sample 1, 95.3-100% and sample 2, 98.5-100%), juniper (81-96.8%) and mint (72.5-99.8%). In the second study, due to a different preparation of concentrations (dilution method), the effect was significantly more dose-dependent, but the most effective oil was again oregano (71.3-93.3%) along with hyssop (42.7-91.3%), coriander (29-92.7%), basil (23.3-93.3%), mint (20-90.3%) and wild mint (13-92.7%). In the first FECRT, a certain anthelmintic effect was achieved with a total reduction in the number of nematode eggs of 25.23% and 24.42% (thyme) and 24.91% and 25.90% (linalool:estragole), but due to the application of the formulations directly in the rumen of animals, the effect was better with oils from the second study, i.e. 43.21% and 60.13% (oregano), 26.86 and 46.04% (mint) and 15.66% and 33.00% (winter savory) on Days 7 and 14, respectively. No toxic or side effects to the sheep were observed for any of the applied oils at the tested doses, neither during the clinical examination of animals nor during haematological and biochemical blood tests, suggesting the safety of their use in sheep. The demonstrated efficacy of the tested oils is related to the compounds that are included in their composition, i.e. above all carvacrol, anethole, thymol, p-cymene, γ-terpinene, carvone, linalool, menthol, α-thujone and cis-pinocamphon, considering their presence in the most effective oils. Four genera of sheep GIN were identified by coproculture examination in both studies, Haemonchus, Trichostrongylus, Teladorsagia and Chabertia, whose percentage representation changed to some extent after the treatments. The use of herbal formulations including EOs in parasite control has numerous advantages. That includes a complex chemical composition with bioactive substances from different chemical groups, which leads to high anthelmintic activity, as well as potentially lower susceptibility to AR development. Furthermore, encapsulation techniques or multiple applications over several consecutive days offer the possibility of further increasing the efficacy in field conditions. On the other hand, the natural origin of these formulations may contribute to lower toxicity for animals and smaller amounts of residues in meat and milk, as well as better environmental acceptability in comparison with commercial drugs. The obtained results suggest the possibility of using the tested EOs in practice, especially oregano, in an integrated control approach designed to reduce the use of commercial drugs and slow down the development of resistance

Chemical Composition of Essential Oils and Compounds with Anthelmintic Potential

Neracionalna upotreba komercijalnih antihelmintika je dovela do razvoja antihelmintičke rezistencije kod mnogih vrsta endoparazita domaćih životinja. Zbog toga se intenzivno istražuju potencijalne alternative, među kojima često i etarska ulja različitih biljaka. Etarska ulja predstavljaju sekundarne metabolite biljaka sa veoma složenim hemijskim sastavom koji najčešće obuhvata veliki broj jedinjenja različitih hemijskih grupa. Najčešće su u pitanju različita terpenska, terpenoidna ili fenilpropanoidna jedinjenja od kojih je veliki broj i identifikovan, pri čemu je važno napomenuti da hemijski sastav etarskih ulja može da varira u zavisnosti od mnogo endogenih i egzogenih faktora. Poznata su mnogobrojna lekovita svojstva etarskih ulja, među kojima i antimikrobno, antiinflamatorno, antioksidativno dejstvo, zbog čega su ovi biljni proizvodi svoju primenu našli u terapiji mnogobrojnih oboljenja. U različitim in vitro i in vivo ispitivanjima je kod mnogih etarskih ulja dokazan i antihelmintički potencijal, a koji potiče od različitih jedinjenja koja ulaze u njihov sastav. Među ovim sastojcima se posebno ističu karvakrol, timol, anetol, cinamaldehid, karvon, limonen, pinen, terpinen, kariofilen, cimen, linalool, geraniol, mentol, borneol, citral, kamfor, eukaliptol, eugenol i mnogi drugi. Njihov izolovani antihelmintički potencijal je takođe potvrđen u mnogim istraživanjima, a ispitane su i njihove različite sinergističke kombinacije. Prisustvo velikog broja jedinjenja sa različitim mehanizmom delovanja pored efikasnosti govori u prilog i manjoj mogućnosti razvoja rezistencije kod samih parazita, a s obzirom da su u pitanju prirodni preparati, i manjoj toksičnosti za životinje u poređenju sa sintetskim preparatima. Zbog toga etarska ulja i njihovi sastojci predstavljaju obećavajuću alternativu u rešenju problema antihelmintičke rezistencije.The irrational use of commercial anthelmintics has led to the development of anthelmintic resistance in many species of domestic animals endoparasites. Therefore, potential alternatives, such as the essential oils of various plants, are being intensively explored. Essential oils are secondary metabolites of plants with a very complex chemical composition that usually includes a large number of compounds of different chemical groups. These are usually various terpene, terpenoid or phenylpropanoid compounds, many of which have been identified, whereby it is important to note that the chemical composition of essential oils can vary depending on many endogenous and exogenous factors. There are numerous documented medicinal attributes of essential oils, including antimicrobial, anti-inflammatory and antioxidant effects, which is why these herbal products have found their application in the treatment of many diseases. In various in vitro and in vivo examinations, essential oils have been shown to have anthelmintic potential, which originates from various compounds that are part of their chemical composition. Among these ingredients, carvacrol, thymol, anethole, cinnamaldehyde, limonene, pinene, terpinene, caryophyllene, cymene, linalool, gernaiol, menthol, borneol, citral, camphor, eucalyptol, eugenol and many others stand out. Their isolated anthelmintic potential has also been confirmed in many studies, and their various synergistic combinations have been investigated. In addition to an increase in efficiency, the presence of a large number of compounds with different mechanisms of action can contribute also to less possibility of the development of resistant helminth strains. Also, the natural origin of essential oils can contribute to their less toxicity to animals compared to synthetic preparations. Therefore, it can be concluded that essential oils and their ingredients represent a promising alternative in combating anthelmintic resistance

An Overview of the Most Important Methods for Examination of the Efficacy of Anthelmintics and Detection of Anthelmintic Resistance

Нерационална примена комерцијалних антихелминтика је довела до развоја антихелминтичке резистенције (АР) код многих врста ендопаразита домаћих животиња. То је довело до смањења ефикасности лекова из група бензимидазола, имидазотиазола и макроцикличних лактона и, последично, до великих економских губитака. Због тога је један од најважнијих приоритета модерног сточарства борба против АР, а која укључује примену адекватних in vitro и in vivo метода за њену детекцију. In vitro методе се заснивају на испитивању утицаја различитих концентрација одређене активне супстанце на одређене изоловане стадијуме паразита у лабораторијским условима. Међу њима су најосетљивије и најчешће коришћење методе тзв. egg hatch assay (EHA) и larval development assay (LDA). Са друге стране, in vivo методе као што је тзв. faecal egg count reduction test (FECRT), подразумевају испитивање утицаја препарата на паразите у самим животињима у теренским условима, где се ефикасност неког лека мери запаженом редукцијом броја одређених паразитских облика након третмана. Свака од наведених метода има своје предности и недостатке, због чега постоје стални напори да се усавршаве и стандардизују. У последње време се у контексту детекције АР све више испитују и користе различите молекуларне технике као што су PCR и пиросеквенцирање. Такође, важно је напоменути да се in vitro и in vivo тестови могу користити и за откривање нових супстанци као што су нека природна једињења са антихелминтичким потенцијалом, као и за испитивање њихове ефикасности. Из свега наведеног се може закључити да наведене методе имају вишеструки значај у борби против антихелминтичке резистенције.The irrational use of commercial anthelmintics has led to the development of anthelmintic resistance (AR) in many species of endoparasites commonly found in domestic animals. This has led to a decrease in the efficiency of drugs from the groups of benzimidazoles, imidazothiazoles and macrocyclic lactones and, consequently, to major economic losses. Therefore, one of the most important priorities of modern animal husbandry is to combat AR, which includes the application of adequate in vitro and in vivo methods for its detection. In vitro methods are based on examining the influence of different concentrations of a certain active substance on certain isolated parasitic stages in lab conditions. Among them, the most sensitive and the most common used methods are the egg hatch assay (EHA) and the larval development assay (LDA). On the other hand, in vivo methods such as the faecal egg count reduction test (FECRT), examine the effect of drug preparations on parasite-infected animals in field conditions, whereby the efficiency of a drug is measured by the observed reduction in the number of certain parasitic forms post-treatment. Each of these methods has its advantages and disadvantages, and efforts are regularly made to improve and standardize them. Recently, in the context of AR detection, various molecular techniques such as PCR and pyrosequencing have been increasingly examined and used. It is also important to note that in vitro and in vivo tests can also be used to detect new substances such as certain natural compounds with anthelmintic potential, and can be simultaneously used to test their efficiency. From the above-mentioned points, it can be concluded that these methods have multiple significance in combating anthelmintic resistance

Examination of the Efficacy of Fluralaner against Poultry Red Mite - Dermanyssus gallinae

Црвена кокошија гриња (lat. Dermanyssus gallinae) представља једног од најзначајнијег паразита модерног живинарства који причањава велике штете. Услед недовољне ефикасности и развоја резистенције према досадашњим акарицидима, проблем је постао још већи, због чега се јавила потреба за проналаском нове активне супстанце која ће ставити под контролу овог паразита. Флураланер, активна супстанца из групе изоксазолина, примењен у дози 0,5 mg/kg t.m., двократно у размаку од 7 дана се наметнуо као могућа опција. Према досадашним истраживањима, флураланер поседује изузетно високу ефикасност и брзину паразитицидног дејства против Dermanyssus gallinae у трајању од најмање три недеље, а такође утиче и на репродуктивни циклус гриња. При свему томе је знатно ефикаснији од осталих, постојећих акарицида. Поред тога, утиче и на повећање производње јер третирање заражених јата флураланером побољшава недељну стопа полагања код кока носиља. Међутим, с обзиром на ограничен број података у досадашњој литератури, потребна су додатна испитивања како би се потврдили досадашњи резултати, а флураланер треба примењивати заједно са другим мерама контроле Dermanyssus gallinae.Poultry red mite (lat. Dermanyssus gallinae) is one of the most important parasites of modern poultry that causes great damage. Due to inadequate efficacy and development of resistance to previous acaricides, the problem has become even greater, which has led to the need to find a new active substance that will put red mite under control. Fluralaner, as an active substance from the group of isoxazoline, administered at a dose of 0,5 mg/kg b.w., twice at the 7-day interval was imposed as a possible option. According to recent research, the fluralaner possesses extremely high efficacy and speed of parasitic kill against Dermanyssus gallinae for at least 3 weeks and also affects the reproductive cycle of mites. In all this, it is significantly more efficient than the other existing acaricides. In addition, it also affects the increase in production because the treatment of infected flies with fluralaner improves the weekly rate of laying on laying hens. However, given the limited number of data in the literature so far, further tests are needed to confirm the results, and the fluralaner should be applied along with other control measures of Dermanyssus gallinae

Influence of Niacin Application on TNF-α, Haptoglobin and Fibrinogen Values in Cows in Peripartal Period

Peripartalni period kod krava predstavlja stanje metaboličkog stresa koje se karakteriše različitim negativnim efektima. U ovom radu su opisani inflamatorni procesi kod krava u peripartalnom periodu. Naime, opisano je delovanje citokina, kao i interakcija citokina, metabolita i jetre kao centralnog metaboličkog organa. Prikazana je inflamacija tkiva u peripartalnom periodu sa posebnim osvrtom na značaj faktora nekroze tumora alfa (TNF-α). U tom kontekstu, ispitan je uticaj aplikacije niacina kod krava na regulisanje inflamatornog odgovora kroz merenje vrednosti TNF-α, haptoglobina i fibrinogena i poređenje sa kontrolnom grupom. Smanjenje koncentracije TNF-α i haptoglobina pod uticajem niacina ukazuje na njegov antiinflamatorni efekat, što sugeriše na značaj njegove primene kod krava u peripartalnom periodu.The peripartum period in cows represents a state of metabolic stress characterized by various negative effects. This paper describes the inflammatory processes in cows during the peripartum period. Namely, it describes the action of cytokines, as well as the interactions of cytokines, metabolites and the liver as the central metabolic organ. Tissue inflammation in the peripartum period is presented with a particular focus on the importance of tumor necrosis factor alpha (TNF-α). Within this context, the influence of niacin application in cows on the regulation of the inflammatory response was examined by measuring the values of the TNF-α, haptoglobin and fibrinogen and comparing it with the control group. The decrease in the concentration of TNF-α and haptoglobin under the influence of niacin indicates its anti-inflammatory effects, which suggests the importance of its use in cows in the peripartum period

Potential Use of Essential Oils against Ovine Gastrointestinal Nematodes - Perspectives and Barriers

Ekonomski gubici koje gastrointestinalne nematode nanose modernom ovčarstvu postaju sve veći usled razvoja rezistencije na sintetske antihelmintike koji se koriste u svakodnevnoj kliničkoj praksi. Zbog toga, istraživači širom sveta, danas tragaju za alternativnim metodama u cilju kontrole ovih parazita. Kao moguća opcija su se zbog svojih osobina, nametnula etarska ulja i biljni proizvodi bogati različitim prirodno aktivnim jedinjenjima. Naime, prema dosadašnjim ispitivanjima, etarska ulja ispoljavaju visoku aktivnost protiv različitih razvojnih stadijuma nematoda, a uz pravilan način primene se generalno dobro tolerišu od strane sisara sa toksikološke strane gledišta. Do sada je dokazana visoka efikasnost velikog broja etarskih ulja protiv gastrointestinalnih nematoda ovaca (različite vrste eukaliptusa, limunske trave, mente, čajevca, timijana, cimeta, đumbira, lavande, crnog pelena i ruzmarina), njihovih aktivnih sastojaka (timol, karvakrol, karvon, anetol, mentol, cinamaldehid, cineol, linalol, vanilin, eugenol, limonen) kao i njihovih kombinacija (npr. cinamaldehid:karvakrol; anetol:karvon) u laboratorijskim uslovima. Međutim, glavno ograničenje za njihovu svakodnevnu primenu predstavlja još uvek nedovoljna efikasnost u terenskim uslovima, a koja potiče od anatomsko-fizioloških specifičnosti vezanih za preživare, kao i od farmakokinetičkih osobina pojedinih etarskih ulja. Ovaj problem bi se mogao prevazići odabirom odgovarajućih etarskih ulja uz adekvatno doziranje, način primene i formulaciju samih ulja, kombinovanom sinergističkom primenom više ulja ili njihovih sastojaka, kao i primenom nanotehnologije. Nevezano za ovaj problem, etarska ulja svakako imaju potencijal da uz kombinaciju sa drugim lekovima i merama, budu deo integrisanog pristupa, dizajniranog da se postigne održiva kontrola parazita u sistemima proizvodnje preživara. Potrebna su dodatna ispitivanja u ovoj oblasti, što se posebno odnosi na istraživanje efikasnosti u terenskim uslovima.The economic losses caused by gastrointestinal nematodes to modern sheep farming are increasing due to the development of resistance to regular anthelmintics used in everyday clinical practice. Therefore, researchers around the world nowadays are looking for alternative methods to control these parasites. Essential oils, herbal products rich in various naturally active compounds, have become a viable option because of their properties. Namely, according to the previous research, essential oils show high activity against all nematode development stages and are generally well tolerated by mammals from the toxicological point of view. So far, high efficacy of a large number of essential oils against sheep gastrointestinal nematodes have been demonstrated (different species of eucalyptus, lemongrass, mint, tea tree, thyme, cinnamon, ginger, mugwort, rosemary etc), their active compounds (thymol, carvacrol, carvone, anethole, menthol, cinnamaldehyde, linalool, vanillin, eugenol, cineole, limonene) as well as their combinations (e.g. cinnamaldehyde:carvacrol; anethole:carvone). However, the main limitation for their everyday use is still insufficient efficacy in field conditions, which originates from the anatomical and physiological specificities associated with ruminants, as well as from the pharmacokinetic properties of certain essential oils. This problem could be overcomed by selecting the appropriate essential oils with adequate dosage, method of application and formulations of oils, by combined synergistic application of multiple oils or their ingredients, as well as the using of nanotechnology. Regardless of this problem, essential oils certainly have the potential to be, in combination with other drugs and measures, part of an integrated approach designed to achieve sustainable parasite control in ruminant production systems. Nevertheless, further examinations on this topic are needed, especially of testing efficacy in field conditions

The Effect of Age on the Concentration of Total Protein, Albumin and Globulin in the Blood Plasma of Chickens

Промене у концентрацији укупних протеина, као и појединачних концентрација албумина и глобулина у крвној плазми често указују на присуство одређених обољења код птица. Међутим, до ових промена може доћи и услед дејства различитих физиолошких фактора, због чега их је неопходно идентификовати и испитати њихов утицај. Циљ овог истраживања је био испитати промену наведених биохемијских параметара у зависности од узраста пилића током производног циклуса (1-42. дан). За овај оглед су коришћени товни хибриди пилића (н=90) који су подељени у три групе у зависности од испитиваног параметра. Унутар сваке групе пилићи су подељени у неколико подгрупа у зависности од узраста (1., 3., 7., 14., 21. и 42. дан). Сви биохемијски параметри су одређивани квантитативном спектрофотометријском методом у лабораторији за биохемију на Пољопривредном факултету у Новом Саду. Раст концентрације албумина је био статистички значајан (п<0,05) између 1. дана (17,41 г/Л) и 3. дана (20,10 г/Л), и наставио се до 14. дана (21,58 г/Л), након чега је стагнирао до краја производног циклуса са забележеном вредношћу од 21,47 г/Л 42. дана. Значајан раст концентрације албумина у прва три дана живота се може објаснити повећаном синтезом албумина у јетри у том периоду. Са друге стране, услед губитка наслеђених имуноглобулина, концентрација глобулина је опадала до 14. дана (26,87 г/Л), такође статистички значајно (п<0,05) у прва три дана (30,42-28,25 г/Л), да би након 14. дана уследио пораст до краја производног циклуса (31,47 г/Л 42. дана) услед продукције антитела од стране пилића. Због оваквих промена у концентрацијама поменутих фракција, концентрација укупних протеина је током целог производног циклуса била у благом порасту (47,83-52,93 г/Л). На основу добијених резултата се може закључити да је узраст један од фактора који утиче на протеински систем крвне плазме птица, што се мора узети у обзир приликом тумачења резултата у свакодневној клиничкој пракси.Changes in the total protein concentration, as well as changes in individual concentrations of albumin and globulin in blood plasma often indicate the presence of certain diseases in birds. However, these changes can also occur due to various physiological factors, which is why they need to be identified and why their influence must be examined. The aim of this study was to examine the change in these biochemical parameters depending on the age of the chickens during the production cycle (day 1-42). Fattened hybrids of chickens (n=90) were used for this experiment, which were divided into three groups depending on the selected parameter. Within each group, the chickens were divided into multiple subgroups depending on age (the 1st, 3rd, 7th, 14th, 21st and 42nd day of age). All biochemical parameters were determined by the quantitative spectrophotometric method in the laboratory of biochemistry at the Faculty of Agriculture in Novi Sad. The increase of the albumin concentration was statistically significant (p<0.05) between day 1 (17.41 g/L) and day 3 (20.10 g/L), and continued to rise up to day 14 (21.58 g/L), after which it entered stagnation by the end of the production cycle with a recorded value of 21.47 g/L on day 42. The significant increase in albumin concentration in the first three days can be explained by the increased synthesis of albumin in the liver during that period. In comparison, due to the loss of inherited immunoglobulin, the globulin concentration was decreasing up to day 14 (26.87 g/L), also at a statistically significant rate (p<0.05) in the first three days (30.42-28.25 g/L). That was followed by an increase up to the end of the production cycle after day 14 (31.47 g/L on day 42) due to the production of antibodies by the chickens. Due to such changes in the concentrations of the mentioned fractions, the total protein concentration was slightly increasing during the entire production cycle (47.83-52.93 g/L). Based on the obtained results, it can be concluded that age is one of the factors which influence the protein system of avian blood plasma. As such, it must be taken into account when interpreting results in everyday clinical practice

Encapsulation and its Significance for Application of Essential Oils in Veterinary Medicine

Upotreba biljnih preparata kao što su etarska ulja, za različite indikacije u veterinarskoj medicini predstavlja veoma aktuelno i perspektivno polje. U tom kontekstu, najčešće se ispituju i dokazuju antibakterijsko, antifungalno i antiparazitsko, ali i mnoga druga lekovita dejstva ovih preparata. Zbog toga se etarska ulja sve više koriste za različite namene, kao što su prevencija dijareje prasadi ili tretiranje kokcidioze živine. Međutim, usled njihove nestabilne prirode i sklonosti ka isparavanju može doći do degradacije i delimične inaktivacije njihovih aktivnih sastojaka u organizmu, što dovodi do ograničene efikasnosti etarskih ulja nakon primene in vivo. Potencijalno rešenje za ovaj problem, mnogi istraživači vide u inovativnim tehnikama inkapsulacije. One predstavljaju postupak zaštite aktivnih komponenti, fizičkim ili hemijskim procesima, pri čemu se formira zaštitni omotač. Zbog toga su ove tehnike emulzifikacije i nanotehnologije našle primenu u različitim granama (industrija hrane, farmacija), a mogle bi biti veoma korisne i kada je u pitanju primena etarskih ulja. Naime, inkapsulacijom se smanjuje interakcija aktivnih supstanci sa različitim faktorima kao i brzina isparavanja, čime bi se mogla umanjiti inaktivacija sastojaka etarskih ulja, povećati bioraspoloživost, a samim tim i efikasnost. Ovo je posebno značajno za primenu protiv bakterija i endoparazita u gastrointestinalnom traktu. Primenom ovih tehnika se omogućava i kontrolisano oslobađanje aktivnih supstanci, što takođe može biti značajno prilikom pojedinih vidova primene kao što je antiektoparazitska. Na kraju, inkapsulacijom se povećava jednostavnost rukovanja aktivnim supstancama, ali i umanjuje neprijatan miris i ukus, što je veoma bitno prilikom primene etarskih ulja u hrani za životinje. Iz svega navedenog se može zaključiti da tehnike inkapsulacije imaju višestruki značaj kada je u pitanju primena etarskih ulja u veterinarskoj praksi, omogućavajući jednostavniju, praktičniju i efikasniju a samim tim i širu primenu ovih prirodnih proizvoda.The use of herbal preparations such as essential oils for various indications in veterinary medicine presents a modern and promising field. Within that context, antibacterial, antifungal and antiparasitic, as well as many other medicinal effects of these substances are most often examined. For that reason, essential oils are increasingly used for different purposes, such as prevention of diarrhoea in piglets or coccidiosis treatment in poultry. However, their unstable and volatile nature may lead to degradation and partial deactivation of their active ingredients in the organism after some in vivo applications. As a potential solution for this problem, many researchers consider innovative encapsulation techniques. They represent the process of protecting the active components by physical or chemical processes, whereby a protective coating is formed. Therefore, these techniques such as emulsification or nanotechnology have found application in various branches (food industry, pharmacy) and could be very useful for the application of essential oils. Namely, encapsulation reduces the interaction of active substances with various factors as well as the rate of evaporation, which could reduce the deactivation of essential oil ingredients, increase bioavailability and thus efficiency (significant for use against the bacteria and endoparasites in the intestinal tract). The application of these techniques also enables the controlled release of active substances, which can also be important for some applications such as antiectoparasitic. Finally, encapsulation increases the ease of application and also reduces unpleasant smells and tastes, which is very important for the use of essential oils in animal feed. From all the above, it can be concluded that encapsulation techniques have multiple implications for the application of essential oils in veterinary practice with enabling simpler, more practical, efficient, and thus wider application of these natural products

Possibilities and Limitations of the Use of Essential Oils in Dogs and Cats

Етарска уља поседују бројна лековита својства која укључују антисептичко, антиинфламаторно, антиканцерогено али и антивирусно, антимикробно и антипаразитско деловање. Међутим, мало је познато о употреби етарских уља код животиња укључујући псе и мачке, иако досадашња истраживања говоре у прилог различитим могућностима њихове примене. Тако су етарска уља показала ефикасност против различитих бактеријских (Staphylococcus spp., Pseudomonas aeruginosa, Enterococcus spp.), гљивичних (Malassezia pachydermatis, Microsporum canis, Trichophyton mentagrophytes), ендопаразитских (Giardia duodenalis, Echinococcus granulosus, Toxocara canis) и ектопаразитских (Otodectes cynotis, Demodex canis, Ctenocephalides felis, неки крпељи и др.) патогена код паса и мачака. При томе, етарска уља поседују бројне позитивне особине као што су богат хемијски састав (висока ефикасност, мања подложност резистенцији), природно порекло итд. Због тога се одређене формулације на бази етарских уља већ користе, попут различитих шампона. Међутим, главно ограничење за употребу ових производа јесте недовољно испитана безбедност примене. Тако се нека етарска уља сматрају токсичним за кућне љубимце, што се посебно односи на мачке. Главни разлог за то је највероватније дефицит појединих ензима јетре који учествују у метаболичким процесима (нпр. УДП – глукуронозилтрансфераза код мачака), што доводи до акумулације појединих активних састојака у организму и њихове токсичности. Због тога је потребан опрез и рационална примена у смислу адекватног одабира биљних врста, дозирања, концентрације и начина примене. Такође, с обзиром да су етарска уља склона испаравању и нестабилности, техником инкапсулације се може додатно повећати њихова in vivo ефикасност, као и омогућити контролисано ослобађање. На тај начин се може смањити потребна доза и додатно повећати сигурност примене.Essential oils have numerous medicinal properties which include antiseptic, anti-inflammatory, anticancer but also antiviral, antimicrobial and antiparasitic effects. Although researches have highlighted different possible application of these oils, little is known about their use in animals including dogs and cats. Specifically, essential oils showed effects against various bacterial (Staphylococcus spp., Pseudomonas aeruginosa, Enterococcus spp.), fungal (Malassezia pachydermatis, Microsporum canis, Trichophyton mentagrophytes), endoparasitic (Giardia duodenalis, Echinococcus granulosus, Toxocara canis) and ectoparasitic (Otodectes cynotis, Demodex canis, Ctenocephalides felis, some ticks etc) pathogens in dogs and cats. In addition, essential oils exhibit numerous positive properties such as complex chemical composition (high efficacy, less susceptibility to resistance), their natural origin etc. Therefore, certain essential oils based formulations are already in use, such as different shampoos. However, the main limitation for the use of these plant products is the insufficiently tested safety of use. Thus, some essential oils are considered toxic to pets, especially when used on cats. The main reason for this is most likely the deficiency of some liver enzymes that are involved in metabolic processes (as UDP-glucuronosyltransferase in cats), which leads to the accumulation of some active ingredients in the organism and their toxicity. Therefore, caution and rational application are needed in terms of adequate selection of plant species, dosage, concentration and the methods of use. In addition, since essential oils are prone to evaporation and instability, the encapsulation technique can further increase their in vivo efficacy as well as enable controlled release. That can reduce the required dose and additionally increase safety of their application

The Effect of Niacin Application on the Development of Inflammation and Cholesterol Metabolism in Cows in Early Lactation

Cilj ovog rada je da se utvrdi uticaj niacina na metabolizam holesterola i ispita kako se istraživani uticaj odražava na zapaljenske procese i funkcionlani status jetre kod krava u ranoj laktaciji. Ogled je izvršen na 30 krava Holštajn-frizijske rase: 15 koje su primale niacin i 15 krava u negativnoj kontroli. Niacin je aplikovan u periodu dve nedelje pre i dve nedelje posle teljenja. Krv je uzimana venepunkcijom v.coccigea kod krava u periodu pre jutarnjeg hranjenja, u momentu teljenja, potom jednu i dve nedelje nakon teljenja. Aplikacija niacina dovodi do smanjenja koncentracije tumor necrosis factor alpha (TNF-α), haptoglobina i nonesterified fatty acid (NEFA), dok na vrednosti fibrinogena nije pokazao značajan efekat. Aplikacija niacina povećava vrednost holesterola, albumina i smanjuje vrednost bilirubina, što je znak boljeg funkcionalnog stanja hepatocita. Niacin pored antilipolitičkog efekta, pokazuje i antiinflamatorni efekat koji može biti značaj mehanizam u zaštiti hepatocita u ranoj laktaciji kod mlečnih krava. Od velikog značaja se pokazao uticaj niacina na TNF-α, jer ovaj citokin kontroliše korelaciju između lipolize i metabolizma holesterola sa inflamatornim odgovorom, posmatrano kroz indeks funkcionalnog statusa jetre.The aim of this study is to determine the effect of niacin on cholesterol metabolism and functional liver status in cows in early lactation. The experiment was performed on 30 Holstein-Friesian cows: 15 receiving niacin and 15 cows in negative control. Niacin was administered for two weeks before and two weeks after calving. Blood was taken by venipuncture of v.coccigea in cows before feeding in the morning, at the time of calving, and then one and two weeks after calving. Niacin administration reduced the concentration of tumor necrosis factor alpha (TNF-α), haptoglobin and nonesterified fatty acid (NEFA), while it showed no significant effect on fibrinogen values. Niacin administration increases cholesterol, albumin, and bilirubin levels, which is a sign of a better functional state of hepatocytes. Niacin, in addition to its antilipolitic effect, also exhibits an anti-inflammatory effect, which may be a significant mechanism in the protection of hepatocytes in early lactation in dairy cows. The influence of niacin on TNF-α has been shown to be of great importance, as this cytokine controls the correlation between lipolysis and cholesterol metabolism with an inflammatory response, viewed through an index of liver functional status