@phdthesis{
author = "Cekić, Bogdan",
year = "2024-01-23",
abstract = "Tanini su, kao velika grupa heterogenih jedinjenja različitog biološkog porekla, široko rasprostranjeni u biljnom svetu. Zbog svoje heterogenosti, tanini ispoljavaju različite efekte u ishrani preživara. Cilj ove doktorske disertacije je bio ispitivanje upotrebe preparata kestenovih tanina u obroku tovne jagnjadi, kako bi se ispitao njihov uticaj na fiziološke i proizvodne pokazatelje.
Ispitivanja su obavljena kroz dva, metodološki različita ogleda. U oba ogleda je uključeno po 30 jagnjadi MIS rase, neposredno nakon završenog perioda odbijanja od majki. Prosečna telesna masa jagnjadi u ogledu 1 je iznosila 20,55 kg, dok je u ogledu 2 iznosila 20,50 kg. U ogledu 1 je korišćen standardni farmski obrok za ishranu odlučene jagnjadi, dok su u ogledu 2 formulisani obroci tako da zadovolje potrebe u metaboličkom proteinu (MP) za prirast od 250 g/dan, dok je neto energije za porast (NEmeat) bilo više za oko 14%, što odgovara prirastu od oko 275 g/dan. Na taj način, su u ogledu 2 korišćena tri obroka uz pretpostavku da će uticaj tanina dovesti do zadovoljenja potreba za prirast veći od 250 g/dan.
Kao izvor tanina korišćen je preparat kestenovih tanina, komercijalnog naziva Farmatan®. U ogledu 1 formirane su tri grupe, sa po 10 jagnjadi, na osnovu sadržaja Farmatan®-a u suvoj materiji (SM) obroka: K (kontrola, bez dodatih tanina); T1 (9,46 g preparata/kg SM obroka) i T2 (18,87 g preparata/kg SM obroka). U ogledu 2, na osnovu sadržaja preparata u obroku, formirane su sledeće grupe: KON (kontrola, bez dodatih tanina); 10T (20,17 g preparata/kg SM obroka) i 20T (40,33 g preparata/ kg SM obroka). Oba ogleda su postavljena kao jednofaktorski ogledi sa po tri tretmana, gde su analizom varijanse testirane razlike između njih, a značajnost razlika između srednjih vrednosti određene na osnovu testa najmanjih razlika (LSD test). Oba ogleda su trajala 60 dana (ne računajući adaptacioni period), tokom kojih je dnevno praćeno konzumiranje SM. Na svakih 15 (u ogledu 1), odnosno 10 dana (u ogledu 2) praćene su promene u telesnoj masi jagnjadi, kako bi se odredili dnevni i ukupni prirasti, kao i parametri iskoristivosti hrane (konverzija, Klajberov odnos - KR, kao i efikasnost proteina - EP i efikasnost energije - EEN). Kako bi se utvrdilo da li tanini mogu uticati na promene vrednosti biohemijskih parametara krvi, u ogledu 1 jagnjadima je uzorkovana krv prvog i poslednjeg dana ogleda, nakon čega su odrađene analize. Određivanje prividne svarljivosti u oba ogleda je utvrđena indirektnom metodom korišćenjem pepela nerastvorljivog u hlorovodoničnoj kiselini kao indikatora, kroz tri kolekciona perioda u oba ogleda. U ogledu 1 kolekcioni periodi su trajali 5 dana, i to od 15. do 19. dana (I period); od 30. do 34. dana (II period) i od 45. do 49. dana ogleda (III period). U ogledu 2, kolekcioni periodi su trajali 6 dana, a obavljani su u periodu od 14. do 19. dana (I period), od 29. do 34. dana (II period) i od 44. do 49. dana (III period). Prividna svarljivost je određena za sledeće parametre: SM, organska materija (OM), SP, sirove masti (SMa), sirova celuloza (SC), deterdžentska vlakna (nerastvorljiva u neutralnom - NDF, odnosno kiselom deterdžentu - ADF), bezazotne ekstraktivne materije (BEM) i nestrukturni ugljeni hidrati (NFC). Po završetku hranidbenog dela ogleda, sva jagnjad su žrtvovana kako bi se ispitale klanične osobine, hemijski i masnokiselinski sastav mesa. Kao dodatni efekat, izvršena je i analiza ekonomske održivosti korišćenja preparata kestenovih tanina u obroku u oba ogleda. Ova analiza je obuhvatila troškove ishrane na osnovu dana (THd), troškove ishrane na osnovu prirasta (THp), neto profit (NP) i ekonomsku isplativost (EKI) korišćenja ovog izvora tanina.
Konzumiranje SM u ogledu 1 je bilo identično kod K i T2 (1,20 kg SM/dan) i veće od T1 (1,13 kg SM/dan), što se pre svega objašnjava slabijim konzumiranjem kabaste komponente obroka (sena) kod ove grupe. Postavka i sprovođenje ogleda 2 je omogućilo konzumiranje slične količine SM kod sve tri grupe, te je prosečno iznosilo 0,97 kg SM, 0,99 kg SM i 1,00 kg SM dnevno za KON, 10T i 20T, redom. Iako se usled adstringentnog ukusa tanina moglo očekivati da će doći do smanjenog konzumiranja, u ispitivanim količinama, kestenovi tanini nisu uticali na ovu pojavu. Razlike u konzumiranju se objašnjavaju kumulativnim efektom promenljivih parametara mikroklime, povremenom izlaganju blagom uznemiravanju, a u ogledu 2 i promenama obroka i hijerarhijskim odnosima u grupi. Iako je poređenje ova dva ogleda moguće sprovesti samo do određene mere, primećuje se da je u ogledu 1 konzumiranje bilo veće u toku celog perioda trajanja ogleda. Takođe, u ogledu 1 je konzumiranje bilo veće nego što korišćeni holandski normativi (CVB, 2018) preporučuju, i gotovo bez ograničenja, dok je u ogledu 2 količina date hrane određivana svakodnevno, na osnovu grupe koja je najslabije konzumirala prethodnog dana.
Na bolju iskoristivost hrane ukazuju veći prirasti pri istom nivou konzumiranja, čime se sugeriše povoljan uticaj kestenovih tanina. Posledično, najbolje konverzije SM, zatim najveće vrednosti KR, EP i EEN u ogledu 1 su ostvarila grla iz grupe T2 (4,46 kg SM/kg prirasta, 0,0181, 1,03 i 27,95), dok su najnepovoljniji parametri bili kod K (5,28, 0,0159, 0,83 i 23,26, redom). U ogledu 2, parametri su podeljeni po polovima, te su konverzije kod muških grla povoljnije kod taninskih (4,50 i 4,33 kg SM/kg prirasta redom za 10T i 20T) nego kod kontrolne (5,05 kg SM/kg prirasta). Uz ovo, kod muških životinja, taninske grupe (10T i 20T, redom) imaju veću vrednost KR (0,0155 i 0,0157), EP (1,47 i 1,60) i EEN (33,15 i 34,79) nego kod kontrolne grupe, kod koje su KR, EP i EEN redom iznosile 0,0137; 1,19 i 26,58). Sličan trend je primećen i kod ženskih grla, te je najbolja konverzija utvrđena kod 10T grupe (4,53), a najlošija kod KON (5,55).
Dalje, u ogledu 1, najveće prosečne dnevne i ukupne priraste su ostvarila grla iz T2 grupe (270,37 g/dan i 16,22 kg), najmanje grla iz K (222,92 g/dan i 13,37 kg) uz primetnu značajnost razlika (p < 0,05). Grla iz T1 su ostvarila priraste od 259,26 g/dan, odnosno 15,55 kg, ali poređenjem sa ostale dve grupe značajnost nije utvrđena (p > 0,05). Slično, u ogledu 2, najveće prosečne dnevne i životne priraste su ostvarila grla iz 20T grupe (230,00 g/dan i 13,80 kg za muška, odnosno 220,00 g/dan i 13,20 kg za ženska grla), koji su značajno veći (p < 0,05) od prirasta postignutih kod KON (191,67 g/dan i 11,50 kg za muška, odnosno 174,17 g/dan i 10,45 kg za ženska grla), dok se ostvareni rezultati kod 10T nisu značajno razlikovali od prethodno dve navedene grupe. Na osnovu rezultata o prirastima za ceo period ogleda, u oba sprovedena ogleda, može se tvrditi da kestenovi tanini u obroku utiču na povećane priraste kod jagnjadi u tovu. Ukoliko se posmatra ceo period ogleda 2 (od 1. do 60. dana), eksperimentalne grupe su ostvarile veće priraste od jagnjadi iz grupa koje nisu dobijale tanine, što može ukazivati na to da kestenovi tanini utiču na poboljšano korišćenje proteina.
Prividna svarljivost SM i OM u ogledu 2 je u prvom kolekcionom periodu (od 14. do 19. dana ogleda) bila, iako slična, nešto veća kod KON (84,02% i 85,23%) nego kod 10T (83,87% i 85,41%) i 20T (80,69% i 82,09%). Svarljivost SP je pratila sličan trend (78,44%, 78,42% i 69,04% za KON, 10T i 20T, redom), dok je svarljivost SMa rasla sa porastom tanina u obroku (83,53%, 89,15% i 90,44%). Trendovi vezani za svarljivost SMa se nastavljaju i u naredne dve kolekcije, što može značiti da su kestenovi tanini uticali na bolje iskorišćavanje masti usled promena u procesima buražne fermentacije. Zaključke vezane za svarljivost SP nije jednostavno doneti zbog eventualnog uticaja tanina na povećanje dotoka SP u tanko crevo. Drugim rečima, usled povećanog dotoka SP dolazi i do povećanja njegovog sadržaja u fecesu, što nužno ne znači njegovu lošiju iskoristivost. U prilog ovome govori i činjenica da su jagnjadi iz taninskih grupa ostvarila veće priraste od onih iz kontrolne.
Ispitivanjem osnovnih parametara krvi u ogledu 1, nisu utvrđeni negativni uticaji kestenovih tanina na jagnjad u tovu.
Iako se u literaturnim navodima uviđa da tanini mogu imati različit uticaj na hemijski sastav i masnokiselinski profil mesa, ovi efekti nisu utvrđeni u okviru disertacije, budući da u oba ogleda nisu utvrđene statističke značajnosti razlika ovih parametara među grupama.
Analiza ekonomske održivosti je pokazala da je vrednost EKI u oba ogleda opadala sa dodavanjem kestenovih tanina u obroke, te je prosečna vrednost ovog parametra iznosila 1,47, 1,29 i 0,98 u ogledu 1 za K, T1 i T2, redom.
U zavisnosti od obroka i pola, vrednost EKI se kretala kod KON 1,30-2,50, kod 10T 0,74-1,56, i kod 20T 0,54-1,06. Ovo ukazuje da kestenovi tanini utiču na smanjenje ekonomske efikasnosti u proizvodnji jagnjadi za tov. Ipak, pored cene preparata, na ovaj parametar utiče i paritet cena, koji je trenutno nepovoljan uz skupa hraniva i nisku cenu žive mere. Kestenovi tanini su uticali na poboljšanje konverzije i veće priraste jagnjadi, što ukazuje na bolju iskoristivost hrane, što je svakako prednost, naročito u velikim farmskim sistemima. Uz činjenicu da troškovi ishrane u stočarstvu čine najveći deo ukupnih troškova proizvodnje, u velikim sistemima, svaki dan skraćenja tova, kao i ušteda svakog kilograma obroka predstavlja veliku stavku u postizanju ekonomski efikasne proizvodnje, te kestenovi tanini predstavljaju potencijalno korisni dodatak u proizvodnji jagnjećeg mesa. Drugim rečima, upotrebu kestenovih tanina u tovu jagnjadi je moguće opravdati u takvim uslovima tržišta koji podrazumevaju jeftiniju proizvodnju hrane i povećanje tržišne cene žive mere jagnjadi.
Prikazani rezultati ukazuju da korišćenjem kestenovih tanina kao aditiva u obrocima jagnjadi u tovu može doći do poboljšanja produktivnih parametara životinja, bez štetnih uticaja. U ispitivanim količinama, kestenovi tanini nisu uticali na pojavu smanjenog konzumiranja hrane, koja se eventualno mogla očekivati usled njihovog adstringentnog ukusa. Takođe, njihovom ingestijom tanini nisu ispoljili štetne uticaje na organizam životinja. Korišćenjem kestenovih tanina došlo je do poboljšanja iskoristivosti hrane, što je rezultiralo većim prirastima i nižim konverzijama u poređenju sa grupama koje nisu konzumirale dodate tanine, što je pre svega posledica boljeg korišćenja proteina. Analizom ekonomske održivosti je utvrđeno da, uz trenutni paritet cena, dodavanje kestenovih tanina u obroku može dovesti do finansijskog opterećenja proizvodnje, te ovo inicijalno deluje kao skupa opcija. Ali, ukoliko bi se postigla jeftinija proizvodnja hrane, uz povećanje tržišne cene jagnjadi, njihova upotreba se može opravdati. Smanjenje troškova proizvodnje se pre svega može ostvariti na velikim farmama, te se potencijal upotrebe kestenovih tanina pre svega u takvim sistemima može iskoristiti, Tannins, as a large group of heterogeneous compounds of different biological origins, are widely distributed in the plant world. Due to their heterogeneity, tannins exhibit various effects in the ruminant nutrition. The aim of this doctoral dissertation was to investigate the use of chestnut tannin product in the diet of fattening lambs to examine its impact on physiological and production indicators.
The research was conducted through two methodologically different experiments. Both experiments included 30 lambs of the MIS breed, immediately after weaning from their mothers. The average body weight of lambs in experiment 1 was 20.55 kg, while in experiment 2, it was 20.50 kg. In experiment 1, a standard farm diet was used for the feeding of the selected lambs, while in experiment 2, diets were formulated to meet the metabolic protein (MP) requirements for a gain of 250 g/day, with net energy for gain (NEmeat) being about 14% higher, equivalent to a gain of about 275 g/day. Thus, in experiment 2, three diets were used assuming that the influence of tannins would lead to meeting gain requirements greater than 250 g/day.
Chestnut tannin product, commercially known as Farmatan®, was used as the source of tannins. In experiment 1, three groups were formed, each consisting of 10 lambs, based on the Farmatan® content in the dry matter (SM) of the diet: K (control, no added tannins); T1 (9.46 g of product/kg of SM diet) and T2 (18.87 g of product/kg of DM diet). In experiment 2, groups were formed based on the following content of the product in the diet: KON (control, no added tannins); 10T (20.17 g of product/kg of SM diet) and 20T (40.33 g of product/kg of SM diet). Both experiments were set up as single-factor designs with three treatments, and differences between them were tested by analysis of variance, with the significance of differences between means determined by the least significant difference (LSD) test. Both experiments lasted for 60 days (excluding the adaptation period), during which daily SM intake was monitored. Changes in lamb body weight were recorded every 15 days (experiment 1) or 10 days (experiment 2) to determine daily and total gains, as well as feed utilization parameters (conversion, Kleiber ratio - KR, protein efficiency - EP, and energy efficiency - EEN).
To investigate whether tannins could influence changes in blood biochemical parameters, blood samples were collected from the lambs in experiment 1 on the first and last days of the experiment, followed by analysis. Apparent digestibility in both experiments was determined using an indirect method with ash insoluble in hydrochloric acid as an indicator during three collection periods in both experiments. In experiment 1, collection periods lasted for 5 days: from day 15 to 19 (Period I), day 30 to 34 (Period II), and day 45 to 49 (Period III). In experiment 2, collection periods lasted for 6 days, and they were conducted from day 14 to 19 (Period I), day 29 to 34 (Period II), and day 44 to 49 (Period III). Apparent digestibility was determined for the following parameters: SM, organic matter (OM), CP, crude fat (SMa), crude fiber (SC), detergent fiber (neutral detergent fiber - NDF and acid detergent fiber - ADF), non-nitrogenous extractives (BEM) and non-fiber carbohydrates (NFC). At the end of the experiments, all lambs were slaughtered to examine the slaughter traits, chemical composition, and fatty acid profile of the meat.
As an additional effect, an analysis of the economic sustainability of using chestnut tannins in the diet in both experiments was conducted. This analysis included feed costs per day (THd), feed costs per gain (THp), net profit (NP), and economic efficiency (EKI) based on the use of this tannin source.
In experiment 1, intake of SM was identical in K and T2 (1.20 kg SM/day) and higher than in T1 (1.13 kg SM/day), primarily explained by lower intake of roughage in this group (hay). The setup and execution of experiment 2 allowed for similar SM intake in all three groups, averaging 0.97 kg DM, 0.99 kg DM, and 1.00 kg DM per day for KON, 10T, and 20T, respectively. Although it could have been expected that the astringent taste of tannins would lead to reduced intake, in the tested amounts, chestnut tannins did not affect this phenomenon. Differences in consumption are explained by the cumulative effect of variable microclimate parameters, occasional exposure to mild stress, and in experiment 2, changes in the diet and hierarchical relationships within the group. While the comparison of these two experiments can only be made to a limited extent, it is noticeable that consumption was higher throughout the duration of experiment 1. In addition, in experiment 1, consumption was higher than the Dutch standards (CVB, 2018) recommended, and almost without limitations, while in experiment 2, the amount of feed given was determined daily based on the group that consumed the least the previous day.
Better feed efficiency is indicated by higher gains at the same level of consumption, suggesting a favorable effect of chestnut tannins. Consequently, the best SM conversion, followed by the highest KR, EP, and EEN values in experiment 1 were achieved by the T2 group (4.46 kg SM/kg gain, 0.0181, 1.03, and 27.95, respectively), while the least favorable parameters were observed in the K group (5.28, 0.0159, 0.83, and 23.26, respectively). In experiment 2, parameters were divided by gender, and feed efficiency was more favorable in male lambs in the tannin groups (10T and 20T, respectively) compared to the control (KON), with SM conversions of 4.50 and 4.33 kg DM/kg gain for 10T and 20T, respectively, while control had 5.05 kg SM/kg gain. Furthermore, in male animals, the tannin groups (10T and 20T) had higher KR values (0.0155 and 0.0157), EP values (1.47 and 1.60), and EEN values (33.15 and 34.79) than the control group, which had KR, EP, and EEN values of 0.0137, 1.19, and 26.58, respectively. A similar trend was observed in female lambs, with the best conversion in the 10T group (4.53) and the worst in the KON group (5.55).
In experiment 1, the highest average daily and total gains were achieved by the T2 group (270.37 g/day and 16.23 kg), and the lowest by the K group (222.92 g/day and 13.37 kg), with significant differences (p < 0.05). The T1 group achieved gains of 259.26 g/day and 15.55 kg, but there were no significant differences compared to the other two groups (p > 0.05). Similarly, in experiment 2, the highest average daily and lifetime gains were achieved by the 20T group (230.00 g/day and 13.80 kg for males, 220.00 g/day and 13.20 kg for females), which were significantly higher (p < 0.05) than the gains achieved by KON (191.67 g/day and 11.50 kg for males, 174.17 g/day and 10.45 kg for females), while the results for 10T were not significantly different from the other two groups. Based on the gain results for the entire experimental period, in both experiments, it can be stated that chestnut tannins in the diet have a positive effect on lamb growth during fattening. If the entire experimental period of experiment 2 (from day 1 to day 60) is considered, the experimental groups achieved higher gains compared to the groups that did not receive tannins, indicating that chestnut tannins improve protein utilization.
In experiment 2, apparent digestibility of SM and OM in the first collection period (from day 14 to 19) was slightly higher in KON (84.02% and 85.23%) compared to 10T (83.87% and 85.41%) and 20T (80.69% and 82.09%). CP digestibility followed a similar trend (78.44%, 78.42%, and 69.04% for KON, 10T, and 20T, respectively), while CF digestibility increased with the addition of tannins in the diet (83.53%, 89.15%, and 90.44%). Trends related to CF digestibility continued in the next two collection periods, indicating that chestnut tannins influenced better fat utilization due to changes in ruminal fermentation processes. Conclusions regarding CP digestibility are not straightforward due to the potential effect of tannins on increased flow of CP into the small intestine. In other words, increased CP flow also leads to an increase in its content in feces, which does not necessarily imply poorer utilization. This is supported by the fact that lambs in the tannin groups achieved higher gains than those in the control group.
In experiment 1, an examination of basic blood parameters did not reveal any negative effects of chestnut tannins on fattening lambs.
Although literature indicates that tannins can have different effects on the chemical composition and fatty acid profile of meat, these effects were not observed in this dissertation, as there were no statistically significant differences in these parameters among the groups in both experiments.
The economic analysis showed that the economic efficiency index (EKI) in both experiments decreased with the addition of chestnut tannins to the diets, with average values of this parameter being 1.47, 1.29, and 0.98 in experiment 1 for K, T1, and T2, respectively. Depending on the diet and gender, EKI values ranged from 1.30 to 2.50 for KON, 0.74 to 1.56 for 10T, and 0.54 to 1.06 for 20T. This indicates that chestnut tannins reduce economic efficiency in lamb production. However, besides the cost of the used tannin product, this parameter depends on the parity of prices, which is currently unfavorable due to expensive feed and low live lamb prices. Chestnut tannins improved feed conversion and increased lamb gains, indicating better feed utilization, which is an advantage, especially in large farm systems. Considering that feed costs in livestock production constitute the largest part of total production costs, in large systems, each day of shortened fattening and every kilogram of saved feed represent significant cost savings, making chestnut tannins a potentially valuable addition to lamb production. In other words, the use of chestnut tannins in lamb fattening can be justified under such market conditions which includes cheaper feed production and higher market prices for live lambs. Cost reduction can primarily be achieved in large farms, so the potential use of chestnut tannins is particularly relevant in such systems.
The presented results indicate that the use of chestnut tannins as additives in lamb diets can lead to improved production parameters without harmful effects. In the tested quantities, chestnut tannins did not affect reduced food consumption, which could have been expected due to their astringent taste. Additionally, their ingestion did not show harmful effects on the animals. The use of chestnut tannins improved feed utilization, resulting in higher gains and lower conversions compared to groups that did not consume tannins, primarily due to better protein utilization. The economic analysis found that, with the current price parity, adding chestnut tannins to the diet can lead to a financial burden in production, making it initially seem like an expensive option. However, if cheaper feed production and higher market prices for live lambs are achieved, their use can be justified. Reduction in production costs can be primarily realized in large farms, so the potential use of chestnut tannins is most suitable for such systems.",
title = "EFEKTI DODAVANJA TANINA NA HRANLJIVU VREDNOST OBROKA I PROIZVODNE REZULTATE JAGNJADI U TOVU, EFFECT OF SUPPLEMENTING TANNINS ON NUTRITIONAL VALUE OF RATION AND PRODUCTIVE RESULTS OF FINISHING LAMBS",
url = "https://hdl.handle.net/21.15107/rcub_ristocar_988"
}
