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Featured researches published by J. Jankowski.


Poultry Science | 2012

The effect of different dietary levels of rapeseed meal on growth performance, carcass traits, and meat quality in turkeys

Dariusz Mikulski; J. Jankowski; Zenon Zduńczyk; J. Juskiewicz; B. A. Slominski

The objective of this study was to determine the effect of different dietary levels of low-glucosinolate rapeseed meal (RSM) on growth performance, blood thyroid hormone concentration, carcass traits, and chemical composition, physicochemical properties, and fatty acid profile of breast meat in growing turkeys. The experiment lasted for 21 wk. Large White BIG-6 turkeys were fed isoenergetic and isonitrogenous diets containing 0, 60, 120, and 180 g/kg of RSM. Each experimental group was comprised of 7 replicates/pen of 28 birds each. There was no effect of graded levels of RSM on final BW. An increase in the inclusion rate of RSM was followed by a linear increase in feed conversion ratio, which was significantly higher (P < 0.05) in the group fed 180 g/kg of RSM. The blood levels of free triiodothyronine decreased significantly (P < 0.05) regardless of the dietary level of RSM. No significant changes in the carcass dressing percentage or the meat fat content were observed. Significant differences were found in the fatty acid composition and physicochemical properties of breast meat. The concentrations of margaroleic acid and saturated fatty acids, including myristic and palmitic acid, in meat from male turkeys fed 120 and 180 g/kg of RSM decreased linearly; whereas the levels of oleic acid and polyunsaturated fatty acids, including linoleic and linolenic acid (an n-3 fatty acid), increased linearly. An increase in RSM content of the diets was accompanied by the unfavorable changes in selected functional properties of meat, including a significant increase in drip loss in groups fed 120 g/kg of RSM (from 1.85 to 2.38%) and 180 g/kg of RSM (from 1.85 to 3.02%) and a decrease in Warner-Bratzler shear force values in turkeys fed 180 g/kg of RSM (from 19.1 to 15.8 N). The results suggest that the quality of turkey meat could be affected by impaired triiodothyronine secretion caused by dietary RSM.


Poultry Science | 2009

The effect of diets containing soybean meal, soybean protein concentrate, and soybean protein isolate of different oligosaccharide content on growth performance and gut function of young turkeys

J. Jankowski; J. Juskiewicz; K. Gulewicz; A. Lecewicz; B. A. Slominski; Zenon Zduńczyk

An experiment was conducted to investigate the effects of diets containing soybean meal (SBM), soybean protein concentrate (SPC), and soybean protein isolate (SPI) on growth performance and gut function of the young turkey. A total of 812 one-day-old male turkey poults were randomly assigned to 4 dietary treatments, with 7 pens per treatment and 29 birds per pen. The 4 experimental diets contained SBM, SBM-SPC, SPC, and SPI and were fed throughout the two 4-wk experimental periods. In each period, the diets were isonitrogenous and isocaloric and contained similar amounts of total and water-soluble nonstarch polysaccharides. The content of oligosaccharides differed among the diets and averaged 2.4, 1.9, 0.9, and 0.1% for SBM, SBM-SPC, SPC, and SPI, respectively. When compared with SBM, birds consuming the SBM-SPC and SPC diets had higher (P<0.05) final BW (4.32 vs. 4.45 and 4.46 kg, respectively). Incorporation of SPI as a substitute for SBM resulted in improved (P<0.05) feed utilization (from 1.76 to 1.67) but did not affect the final BW. Significant changes in cecal concentrations of short-chain fatty acids were observed and averaged 130, 103, and 89 micromol/g of digesta for the SBM, SBM-SPC, and SPC diets, respectively. This coincided with the proportional decrease in dietary oligosaccharide content (from 2.4 to 0.9%) and was further substantiated by a significant decrease in ileum weights. Feeding the SPI diet resulted in the lowest ileal and cecal tissue weights as well as the lowest cecal short-chain fatty acids concentration. There was no effect of diet on digesta pH, viscosity, and mucosal sucrase and maltase activities. Bacterial beta-glucuronidase activity was decreased (P=0.08) in the cecum (from 0.98 to 0.60 U/g) with decreased dietary oligosaccharide content. In conclusion, partial or almost complete substitution of SBM with SPC suppressed the fermentation processes in the ceca but enhanced the growth rate. Substitution of SBM with SPI significantly improved feed utilization but decreased BW of 4-wk-old turkeys with no effect on growth rate of older 8-wk-old birds.


Worlds Poultry Science Journal | 2004

Selected parameters of gastrointestinal tract metabolism of turkeys fed diets with flavomycin and different inulin content

Jerzy Juśkiewicz; Zenon Zduńczyk; J. Jankowski

For 16 weeks, turkeys were fed the following feed mixtures: control diet without antibiotic (or inulin), diet with flavomycin (8 mg/kg) and diets with different level of inulin: low (0.1% for 16 weeks), medium (0.4% and 0.2% in the first and second 8-week period, respectively) and high (1 % and 0.4% in the first and the second 8-week period of the experiment). During the first 8 weeks, dietary intake and feed conversion were similar in all groups. A high content of inulin in a diet caused lower body weight gain of turkeys compared to the remaining groups. In this period coefficients of protein digestibility (85.7-86.8%), concentration of dry matter and ammonia in faeces were alike in all groups. Faeces of turkeys fed a diet supplemented with inulin were characterised with a lower pH (5.48-5.56) than these of turkeys from the control group (5.77) as well as with lower activity of microbial β-glucuronidase (0.52-0.79 U/g and 1.01, respectively). The lowest faecal β-glucuronidase activity was in group with flavomycin (0.44). The addition of an antibiotic or inulin did not increase the final body weight of the turkeys; moreover the birds fed with the highest dose of inulin were the lightest. The influence of the experimental diets on ileal parameters was low; they affected however functioning of the caeca. The share of flavomycin in the mixture lowered the activity of microbial α-glucosidase, to some extent enhanced pH of digesta, but did not lower SCFAs concentration. As a result of increased amount of caecal digesta, the total sum of SCFAs produced was higher than in the control group. Higher doses (0.4/0.2% and 1.0/0.4%) of inulin in a diet caused a beneficial pH decrease in digesta (6.84 and 6.92, respectively), compared to lower doses of this preparation (7.12). On the other hand, they evoked a disadvantageous increase in the ammonia concentration in the caeca (1.188 and 1.240 mg/g in digesta of groups Inulin-M and Inulin-H, compared to 1.109 mg/g in digesta of group Inulin-L). Increasing the inulin dose in a diet up to 1% did not increase the activity of microbial enzymes, while increased significantly the concentration and amount of SCFAs in the caeca compared to limited dose (0.1%) of inulin preparation.


Poultry Science | 2015

In ovo injection of prebiotics and synbiotics affects the digestive potency of the pancreas in growing chickens

E. Pruszynska-Oszmalek; P. A. Kolodziejski; Katarzyna Stadnicka; M. Sassek; D. Chalupka; B. Kuston; L. Nogowski; P. Mackowiak; Giuseppe Maiorano; J. Jankowski; Marek Bednarczyk

The purpose of the study was to examine the effect of 2 prebiotics and 2 synbiotics on the digestive potency of pancreas in 1-, 3-, 7-, 14-, 21-, and 34-day-old cockerels. Prebiotics (inulin and Bi²tos) and synbiotics (inulin + Lactococcus lactis subsp. lactis and Bi²tos + Lactococcus lactis subsp. cremoris) were injected in ovo into the air cell on the 12th d embryonic development. Their application increased the activity of amylase, lipase, and trypsin in the pancreas. The most pronounced changes were observed at the end of the investigated rearing period (d 34). The strongest stimulative effects on amylase were shown by both synbiotics, on lipase synbiotic Bi²tos + Lactococcus lactis subsp. cremoris, and on trypsin all the used prebiotics and synbiotics. Simultaneously, neither the absolute nor the relative mass of the pancreas in comparison to control group were changed. Also, the injected in ovo compounds did not cause a deterioration in the posthatching condition of the chicken liver, as determined by measurement of the activity of marker enzymes in the blood (alanine aminotransferase and aspartate aminotransferase). Treatment with the prebiotics and synbiotics did not change the feed conversion ratio but Bi²tos (galacto-oligosaccharide) and inulin (fructan) + Lactococcus lactis subsp. lactis significantly increased final BW.


Poultry Science | 2011

Effect of organic and inorganic forms of selenium in diets on turkey semen quality.

Mariola Słowińska; J. Jankowski; Grzegorz J. Dietrich; Halina Karol; Ewa Liszewska; Jan Glogowski; Krzysztof Kozłowski; K. Sartowska; Andrzej Ciereszko

The effects of Se supplementation and its organic or inorganic form on semen quantitative parameters (ejaculate volume, sperm concentration, and total number of sperm) and biochemical parameters of seminal plasma (protein concentration, acid phosphatase activity, superoxide dismutase activity, and total antioxidant capacity) were investigated over a 25-wk reproductive season. Additionally, DNA fragmentation and motility characteristics of turkey spermatozoa were measured. The parameters of turkey semen in relation to yellow semen syndrome were also determined. Twenty-four males (Big 6) were divided into 3 experimental groups differing in form of Se supplementation (no Se supplementation, 0.3 mg/kg of inorganic Se from sodium selenite and 0.3 mg/kg of organic Se from Sel-Plex, Alltech Inc., Nicholasville, KY). Dietary Se supplementation enhanced the sperm concentration and total number of sperm and did not influence the antioxidative properties of turkey seminal plasma and most biochemical parameters. Only seminal plasma acid phosphatase activity was increased in turkeys fed inorganic Se. The main sperm DNA fragmentation parameters were not affected by dietary Se. The highest percentage of motile spermatozoa (85%) was recorded for the semen of turkeys fed organic Se. Values of the biochemical parameters (acid phosphatase, superoxide dismutase, total antioxidant capacity) of seminal plasma increased during the reproductive season. Yellow semen was characterized by increased biochemical parameters and decreased spermatozoa motility characteristics. However, the percentage of motile spermatozoa did not differ between white and yellow semen. Organic Se seemed to be the preferred form of diet supplementation in comparison with inorganic Se. Biochemical parameters of semen and spermatozoa motility parameters appear to be useful for evaluating the effect of age on semen quality. Monitoring the DNA fragmentation of spermatozoa at the end of the reproductive season could be a useful tool for monitoring turkey semen quality. Increased superoxide dismutase activity can be used as an indicator of yellow semen. A decline in the quality of yellow semen can be related to a decrease in the spermatozoa motility parameters of turkeys.


Annals of Animal Science | 2013

Poultry Meat as Functional Food: Modification of the Fatty Acid Profile – A Review / Mięso drobiowe jako żywność funkcjonalna: modyfikacja profilu kwasów tłuszczowych – artykuł przeglądowy

Zenon Zduńczyk; J. Jankowski

Abstract Functional foods, defined as “foods that may provide health benefits beyond basic nutrition”, became increasingly popular in the past twenty years with numerous practical applications. In Europe, functional foods must be accompanied by scientifically substantiated health claims. Products which aspire to that category include poultry meat and processed meat products which have been modified through bird nutrition. This article reviews the existing knowledge about foods fortified with health-promoting additives. It discusses the physiological, economic and legal aspects of modifying poultry meat, including turkey meat which has been poorly investigated in this context. The addition of oils rich in PUFA (polyunsaturated fatty acids), e.g. linseed oil, to poultry diets has been found to increase LC n-3 PUFA (long-chain omega-3 PUFA) concentrations in chicken and turkey meat. LC n-3 PUFAs participate in many processes that condition metabolism and health, and the nutritional value of meat, including poultry, is most commonly enhanced by increasing the proportion of LC n-3 PUFAs in the products fatty acid composition. However, it increases feed costs and may cause a deterioration in the sensory attributes and oxidative stability of meat. Turkey breast meat is characterized by a relatively low fat content, which is why the fulfilment of health claim requirements is difficult in the European Union. Streszczenie W ostatnim dwudziestoleciu koncepcja żywności funkcjonalnej, rozumianej jako żywność, któ- ra - poza wartością odżywczą - może zapewniać korzyści zdrowotne, znalazła liczne zastosowania praktyczne i trwałą pozycję na rynku żywności. Do tego typu żywności, wymagającej w Europie od- powiedniego oznaczenie zdrowotnego, pretenduje mięso i wyroby mięsne z drobiu, zmodyfikowane prozdrowotnie poprzez odpowiednie żywienie ptaków. Ze względu na fakt, że długołańcuchowe wie- lonienasycone kwasy tłuszczowe uczestniczą w wielu procesach warunkujących prawidłowy metabo- lizm i zdrowie organizmu, zwiększenie udziału tej grupy w produktach jest najbardziej popularnym kierunkiem prozdrowotnej modyfikacji produktów pochodzenia zwierzęcego, w tym mięsa drobiowego. W niniejszym przeglądzie piśmiennictwa podsumowano aktualną wiedzę na ten temat. W nawiązaniu do potrzeb profilaktyki zdrowotnej u ludzi przedstawiono fizjologiczne, ekonomiczne i prawne uwarunko- wania żywieniowej modyfikacji mięsa drobiowego, w tym mięsa indyczego, którego dotyczą nieliczne doświadczenia. Wykazano, że skuteczną metodą zwiększenia zawartości wielonienasyconych kwasów tłuszczowych w mięsie kurcząt i indyków jest zastosowanie oleju lnianego w diecie tych ptaków. Taki zabieg zwiększa koszt paszy oraz może pogarszać cechy sensoryczne i stabilność oksydacyjną mięsa. Ze względu na mniejszą zawartość tłuszczu w piersi indyków spełnienie unijnych wymagań niezbędnych do oznaczenia zdrowotnego tego produktu jest znaczniej trudniejsze.


Journal of Agricultural and Food Chemistry | 2012

Low-fiber canola. Part 2. Nutritive value of the meal.

Wei Jia; Dariusz Mikulski; Anna Rogiewicz; Zenon Zduńczyk; J. Jankowski; B. A. Slominski

The nutritive value of meals derived from black- and yellow-seeded Brassica napus and canola-quality Brassica juncea was determined with broiler chickens and young turkeys. A higher apparent ileal digestibility of total amino acids was observed in chickens fed diet containing yellow-seeded B. napus than in those fed conventional black-seeded B. napus or canola-quality B. juncea (88.8 vs 83.4 and 84.2%, P < 0.05). Metabolizable energy (AME(n)) contents for yellow- and black-seeded B. napus and B. juncea as determined with broiler chickens were 2190, 1904, and 1736 kcal/kg DM, respectively. In the turkey assay, the AME(n) values for yellow- and black-seeded B. napus and B. juncea canola averaged 2166, 2007, and 1877 kcal/kg DM, respectively. Multicarbohydrase enzyme addition to broiler chicken diets increased energy utilization (from 1943 to 2249 kcal/kg DM, on average), with the most pronounced effect observed for B. juncea canola (from 1736 to 2356 kcal/kg DM).


Journal of Animal Physiology and Animal Nutrition | 2011

Effects of dietary addition of Macleaya cordata alkaloid extract on growth performance, caecal indices and breast meat fatty acids profile in male broilers

J. Juskiewicz; R. Gruzauskas; Zenon Zduńczyk; A. Semaskaite; J. Jankowski; Z. Totilas; V. Jarule; V. Sasyte; Przemysław Zduńczyk; A. Raceviciute-Stupeliene; G. Svirmickas

The aim of this experiment was to investigate whether a low-dietary application (15 mg/kg) of an alkaloid preparation containing quaternary benzo[c]phenanthridine alkaloids and obtained from Macleaya cordata (Sangrovit) influenced caecal metabolism, growth performance and long-chain fatty acid composition of breast meat. One-day-old broiler chicks (Cobb 500) were fed a diet without supplement or with a 15 mg/kg dose of Sangrovit (C and A groups respectively) for 5 weeks. Although the A treatment was not accompanied by an enhanced final body weight of broilers, the intake of a diet with Sangrovit influenced the caecal microflora activity. The addition of Sangrovit to a diet decreased potentially harmful β-glucuronidase and β-glucosidase activities (p<0.05 and p=0.075 respectively), and at the same time led to a significant increase in activities of bacterial glycolytic enzymes α-glucosidase, α-galactosidase, β-galactosidase in comparison to the control group. The concentration of total short-chain fatty acids in the caecal digesta was increased in the A treatment contributing to the tendency towards lower caecal pH (p=0.078). The analysis of breast meat fatty acids showed that the dietary application of Sangrovit evoked some changes in contents of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) contents. The applied dosage of Sangrovit caused an increase in the sum of MUFA and the tendency towards lower PUFA sum (p<0.05 and p=0.062 respectively) as in relation with the C group. Although the nutritionally relevant n-6/n-3 PUFA and the (PUFA+MUFA)/saturated fatty acids ratios remained similar in both groups, further research is postulated to establish the effect of this preparation on meat quality. To sum up, despite of a lack of the improvement in final body weight, a low dose of dietary Sangrovit was found to exert positive effects on the caecal metabolism of the broilers.


Canadian Journal of Animal Science | 2013

Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys

Zenon Zduńczyk; J. Jankowski; Jerzy Juśkiewicz; Dariusz Mikulski; B. A. Slominski

Zdunczyk, Z., Jankowski, J., Juskiewicz, J., Mikulski, D. and Slominski, B. A. 2013. Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys. Can. J. Anim. Sci. 93: 353-362. One-day-old male turkey poults were randomly assigned to eight dietary treatments and were fed diets containing 0, 60, 120, or 180 g kg-1 of low-glucosinolate rapeseed meal (RSM) from 1 to 56 d of age without or with a commercial non-starch polysaccharide-degrading enzyme product containing pectinase, cellulase, xylanase, glucanase, mannanase and galactanase activities. There were no significant differences (P>0.05) in body weight and feed conversion ratio between the Control soybean meal-based diet and the diets containing RSM. Overall, the inclusion of up to 180 g kg-1 of RSM did not affect the growth performance of turkeys. When compared with the Control treatment, the diet with the lowest RSM content increased the pH of the small intestinal contents and the amounts of cecal digesta. The moderate level of RSM also increased the pH of the small intestinal contents although no increase in the cecal digesta contents was noted. In comparison with other treatments, the highest RSM content increased the content of the small intestinal digesta considerably and decreased the pH of the small intestinal contents to that of the Control treatment. All three dietary levels of RSM significantly reduced the activity of bacterial β-glucuronidase in the ceca. Enzyme supplementation tended to reduce ileal viscosity (P=0.079), decreased ammonia concentration, increased the glycolytic activities of the intestinal microflora enzymes a-glucosidase, a-galactosidase, and β-galactosidase, decreased the activity of β-glucuronidase and increased the growth rate of turkeys.


Annals of Animal Science | 2014

Nutritional and immunomodulatory function of methionine in poultry diets – a review

J. Jankowski; Magdalena Kubińska; Zenon Zduńczyk

Abstract Methionine (Met) plays many important metabolic functions in humans and animals, and therefore may be classified as a functional amino acid (AA). Functional AAs are defined as those AAs that participate in and regulate key metabolic pathways to improve health, survival, growth, development, and reproduction of organisms. As the first-limiting AA in poultry diets, Met affects poultry production parameters such as body weight gains, feed conversion ratio and carcass quality. The results of many experiments on chickens fed diets with different levels of Met (from 0.3 to 1.2% in the starter period, and from 0.3 to 0.9% in the grower period) indicate that commercial broiler chickens do not require more than 0.50 and 0.38% Met in starter and grower diets, respectively, for optimum growth and feed efficiency, whereas higher inclusion rates of Met are needed to stimulate immune responses. The results of recent experiments on chickens are insufficient to define the optimal dietary levels of Met, which has been shown to exert immunostimulatory activity. A few experiments on layer hens have demonstrated that Met requirements for immune competence are higher than for optimum production, but the inclusion levels of this AA needed to stimulate the immune system of birds have not been defined. In the absence of such research, it remains unknown whether feeding growing turkeys diets supplemented with Met above NCR recommendations, as suggested by B.U.T. (British United Turkeys), stimulates the immune system of birds.

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Zenon Zduńczyk

Polish Academy of Sciences

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Dariusz Mikulski

University of Warmia and Mazury in Olsztyn

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Jerzy Juśkiewicz

Polish Academy of Sciences

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J. Juskiewicz

Polish Academy of Sciences

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Krzysztof Kozłowski

University of Warmia and Mazury in Olsztyn

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Andrzej Ciereszko

Polish Academy of Sciences

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Andrzej Koncicki

University of Warmia and Mazury in Olsztyn

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Magdalena Kubińska

University of Warmia and Mazury in Olsztyn

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