Search

Oak acorn is widely used in livestock feeding due to its low price but in order to use it in the diet of aquatic animals, it is necessary to study the effect of the feed manufacturing process on its usability. Four diets containing: 1) 17% extruded wheat flour, 2) 5% non-extruded wheat flour and 12% extruded wheat flour, 3) 5% non-extruded oak acorn flour and 12% extruded wheat flour, and 4) 5% of extruded oak acorn flour and 12% of extruded wheat flour were evaluated in a completely randomized design with three replicates for each treatment. The fish were reared in round plastic tanks with a volume of 250 liters and a density of 15 fish with an average initial weight of 5.42 ± 0.03 g in each tank. After 8 weeks, the highest weight and total length of fish were observed in treatment 4, so that there was a significant difference with treatment 3 (P<0.05). The amount of protein in the enzyme extract of treatment 1 was significantly higher than other treatments (P<0.05). The highest protease activity was observed in treatment 2, which was significantly different from treatment 3 (P<0.05). Protein digestibility in treatment 2 was significantly higher than other treatments (P<0.05). Significantly, the highest amylase activity was observed in treatment 2 and the lowest carbohydrate digestibility was recorded in treatment 3 (P<0.05). Based on growth indicators, digestive enzyme activity and protein and carbohydrate digestibility, it is recommended to consume oak acorn flour at the level of 5% of common carp extruded diet. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of different levels of oak Acorn on the biodiversity of rumen epimural bacterial population using PCR-SSCP molecular technique in Merkhoz goats. A total of 24 Markhoz goats with a mean BW of 16.93±1.25 kg and an average age of 4-5 months were tested in a completely randomized design with 4 treatments and 6 replications for 105 days. Experimental treatments included 1) control diet, 2) diet containing 8% oak acorn, 3) diet containing 17% oak acorn and 4) diet containing 25% oak acorn. The results showed that the effect of diet on biodiversity of rumen bacterial epimural community was significant (P <0.001). There was no significant difference between other experimental treatments (P> 0.05), although treatments containing 8% and 17% oak had more variety than treatments containing 25% oak. Sampling site had no effect on biodiversity of rumen bacterial epimural community (P> 0.05). The highest value of Shannon index was related to ventral ruminal site and the lowest was related to reticulum. The interaction effect of diet and sampling position on biodiversity of rumen bacterial epimural community was significant (P> 0.05). The results showed that the use of oak acorn up to 17% in the diet increased the biodiversity of the of rumen bacterial epimural community, while the use of 25% oak in the diet decreased the biodiversity of the rumen bacterial epimural community. [ABSTRACT FROM AUTHOR]

The influences of oak inclusion into the diet of ruminants on performance, feed digestibility, milk production and blood metabolites are reviewed herein. Oak as an alternative and available feed are being utilized in many parts of the world, especially in areas suffering from a shortage of feed ingredients. It is evident that different oak species have different impacts on various animal species. Oak fed at low levels in the diet may not affect digestibility, but when they are fed at high level may lead to lessen the digestibility of dry matter. Adding oak products may improve the daily milk yield of goats. Feeding oak acorns and leaves to growing goat kids might not been accompanied by significant improvement in daily weight gain and feed conversion ratio, while when feeding adult sheep on high level of dietary oak, it may result in lowered daily weight gain. Different oak species produce different amounts of tannins, which after ingestion by animals, act to form complexes with the proteins of diet, this may lead to lower digestibility of nutrients or may beneficially affect to positive flow of amino acids into abomasum and small intestine by reducing the protein degradability in the rumen. Thus, the extent of the impact of dietary oak on ruminants’ performance depends on the species of both animals and oak, and the level of oak being used in the diet.

Quercus spp. (Oak) has been used in traditional medicine due to its medicinal properties for centuries. However, its effect on wound healing in the skin is well unknown. This experimental trial was performed to evaluate in vivo wound healing of Oak acorn in the skin of rats. In the present trial, 24 Wistar albino rats were allocated to three groups equally, control (n = 8), Madecassol® (n = 8), and Oak acorn (n = 8). The circular excision wound models by biopsy punch device were applied in the interscapular region in rats. Oak acorn and Madecassol® pomade have been applied to experimental groups per day and normal saline solution and glycerin have been given to the control group locally as placebo. Blood and skin tissue were collected to evaluate histopathological and biochemical alterations on days 7th and 15th. In comparison with the control group, the topical administration of Oak acorn showed definite effects on epithelization, proliferative impacts on fibroblast cells, and enhancing effect on collagen formation by reducing inflammation and edema. Biochemical investigations of skin and blood tissues exhibited that fluctuated malondialdehyde and antioxidant defense system components were rehabilitated in the Oak acorn group. This experimental study revealed that pomade obtained from the Oak acorn displays remarkable wound-healing activity.

The influences of oak inclusion into the diet of ruminants on performance, feed digestibility, milk production and blood metabolites are reviewed herein. Oak as an alternative and available feed are being utilized in many parts of the world, especially in areas suffering from shortage of feed ingredients. It is evident that different oak species have different impacts on various animal species. Oak fed at low levels in the diet may not affect digestibility, but when they are fed at high level may lead to lessen the digestibility of dry matter. Adding oak products may improve the daily milk yield of goats. Feeding oak acorns and leaves to growing goat kids might not been accompanied by significant improvement in daily weight gain and feed conversion ratio, while when feeding adult sheep on high level of dietary oak, it may result in lowered daily weight gain. Different oak species produce different amounts of tannins, which after ingestion by animals, act to form complexes with the proteins of diet, this may lead to lower digestibility of nutrients or may beneficially affect to positive flow of amino acids into abomasum and small intestine by reducing the protein degradability in the rumen. Thus, the extent of the impact of dietary oak on ruminants’ performance depends on the species of both animals and oak, and the level of oak being used in the diet. [ABSTRACT FROM AUTHOR]

Abstract Key message Quercus ilex populations from cold habitats display a large lag between seed germination and shoot emergence time, favouring avoidance of late frost events. Populations from mild habitats show the fastest seed germination and shoot emergence rates at moderate temperatures, enabling them to synchronize germination in the late winter-early spring period and a rapid seed-to-seedling transition, during the favourable rainy period. Context Quercus ilex is the most abundant and representative Mediterranean oak species. Identifying and describing intraspecific variation in seed traits is necessary to characterize the germination niche, and to elucidate drivers of species’ range. Aims In order to identify adaptations to local environments that may reflect ecological strategies for stress avoidance and seed survival, we tested under common and optimal conditions whether seed functional traits vary, in Quercus ilex subsp. rotundifolia Lam., along climatic gradients within its distribution range in Tunisia. Methods We have explored variations in seed morphological traits, desiccation sensitivity level, germination and shoot emergence rates under different controlled temperature conditions, among 15 populations of Q. ilex sampled throughout the Tunisian distribution of the species. Results Significant between-populations differences were observed for morphological seed traits but no relationships could be established with the climate of the sampling sites. In contrast, key physiological traits varied significantly with elevation and temperature. Specifically, mild temperatures in lowland regions were associated with higher seed moisture content, fast germination and shoot emergence rates at moderate temperatures (13 °C) for germination. Seeds of Q. ilex populations from cold sites displayed the fastest germination rates at low temperatures (5 °C) as well as the greatest lag between seed germination and shoot emergence time. Conclusion Intraspecific variation in seed physiological traits is significantly associated with local climate. This functional diversity should be considered when evaluating germplasm and predicting suitability for reforestation and assisted migration programs.

Today, oak fruit as a food ingredient is identified as a substitute for corn in the poultry industry. However, this fruit contains significant amounts of phenolic compounds, such as tannins, which limits its use in poultry diets. Generally, food ingredients containing phenolic compounds can affect the expression of genes in the immune system. Therefore, the aim of this study was to investigate the effect of different levels of oak acorn on the expression of interleukin-5 (IL-5) and interleukin-6 (IL-6) genes in the bursa Fabricius tissue of broiler chickens. In this study, three diets containing zero, 15% and 20% oak fruits were used to feed broiler chicks in a 42-day period. Total RNA were extracted from bursa Fabricius tissue of 6 chickens for each treatment (18 broiler chickens) on day 42. The expression levels of IL-5 and IL-6 genes were normalized with β-actin gene as a reference gene. To analyze the gene expression data, REST, 2009, V2.0.13 software was used. The results of this study showed that expression of IL-6 gene in bursa Fabricius was not significantly different between treatments at day 42 although its expression in the treatment of 20% of oak acorn was decreasing. The expression of IL-5 gene in bursa Fabricius was significantly decreased in 15% and 20% oak acorn treatments compared to control group. Generally, replacing 15 to 20% of dietary corn with oak acorn can reduce the expression of immune system genes in the tissue of the Bursa Fabricius in broilers due to increased phenolic compounds in the diet. Therefore, it is recommended that lower levels of oak acorn be used in diet of broiler chickens. [ABSTRACT FROM AUTHOR]

Quercus spp. (Oak) has been used in traditional medicine due to its medicinal properties for centuries. However, its effect on wound healing in the skin is well unknown. This experimental trial was performed to evaluate in vivo wound healing of Oak acorn in the skin of rats. In the present trial, 24 Wistar albino rats were allocated to three groups equally, control (n = 8), Madecassol® (n = 8), and Oak acorn (n = 8). The circular excision wound models by biopsy punch device were applied in the interscapular region in rats. Oak acorn and Madecassol® pomade have been applied to experimental groups per day and normal saline solution and glycerin have been given to the control group locally as placebo. Blood and skin tissue were collected to evaluate histopathological and biochemical alterations on days 7th and 15th. In comparison with the control group, the topical administration of Oak acorn showed definite effects on epithelization, proliferative impacts on fibroblast cells, and enhancing effect on collagen formation by reducing inflammation and edema. Biochemical investigations of skin and blood tissues exhibited that fluctuated malondialdehyde and antioxidant defense system components were rehabilitated in the Oak acorn group. This experimental study revealed that pomade obtained from the Oak acorn displays remarkable woundhealing activity. [ABSTRACT FROM AUTHOR]

Key message: Quercus ilex populations from cold habitats display a large lag between seed germination and shoot emergence time, favouring avoidance of late frost events. Populations from mild habitats show the fastest seed germination and shoot emergence rates at moderate temperatures, enabling them to synchronize germination in the late winter-early spring period and a rapid seed-to-seedling transition, during the favourable rainy period. Context: Quercus ilex is the most abundant and representative Mediterranean oak species. Identifying and describing intraspecific variation in seed traits is necessary to characterize the germination niche, and to elucidate drivers of species' range. Aims: In order to identify adaptations to local environments that may reflect ecological strategies for stress avoidance and seed survival, we tested under common and optimal conditions whether seed functional traits vary, in Quercus ilex subsp. rotundifolia Lam., along climatic gradients within its distribution range in Tunisia. Methods: We have explored variations in seed morphological traits, desiccation sensitivity level, germination and shoot emergence rates under different controlled temperature conditions, among 15 populations of Q. ilex sampled throughout the Tunisian distribution of the species. Results: Significant between-populations differences were observed for morphological seed traits but no relationships could be established with the climate of the sampling sites. In contrast, key physiological traits varied significantly with elevation and temperature. Specifically, mild temperatures in lowland regions were associated with higher seed moisture content, fast germination and shoot emergence rates at moderate temperatures (13 °C) for germination. Seeds of Q. ilex populations from cold sites displayed the fastest germination rates at low temperatures (5 °C) as well as the greatest lag between seed germination and shoot emergence time. Conclusion: Intraspecific variation in seed physiological traits is significantly associated with local climate. This functional diversity should be considered when evaluating germplasm and predicting suitability for reforestation and assisted migration programs. [ABSTRACT FROM AUTHOR]

Oak acorn is widely used as human food and animal feed. This fruit contains considerable amounts of tannin. A large amount of tannin causes a disturbance in the digestion process. The aim of this study was to reduce the amount of tannin before consuming oak acorn in the diet. Dry and de-hulled acorns were soaked in tap water (1:5; w/v) for 24, 48 and 72 h (treatments 1, 2 and 3 without water exchange and treatments 4, 5 and 6 with water change every 12 h, respectively) at 50 °C. Then acorns were dried at 60 °C for 24 h, milled and sieved with a 250-micron sieve. The highest loss of total phenolic compounds (93.34%), non-tannin phenolic compounds (95.83%) and condensed tannins (96.92%) and the highest increase in protein digestibility were observed in treatment 6 (p

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oak acorn is widely used as human food and animal feed. This fruit contains considerable amounts of tannin. A large amount of tannin causes a disturbance in the digestion process. The aim of this study was to reduce the amount of tannin before consuming oak acorn in the diet. Dry and dehulled acorns were soaked in tap water (1:5; w/v) for 24, 48 and 72 h (treatments 1, 2 and 3 without water exchange and treatments 4, 5 and 6 with water change every 12 h, respectively) at 50 °C. Then acorns were dried at 60 °C for 24 h, milled and sieved with a 250-micron sieve. The highest loss of total phenolic compounds (93.34%), non-tannin phenolic compounds (95.83%) and condensed tannins (96.92%) and the highest increase in protein digestibility were observed in treatment 6 (p<0.05). Carbohydrate digestibility only in treatment 2 was higher than the control, and the increased soaking time from 48 to 72 h caused a significant decrease in the digestibility of the carbohydrate. Acorn soaking caused a significant elevation in pH in treatment 6. The pH value of digested acorn was not different from the control when water was not changed, however, it was higher than the control when water was changed. In general, treatment 6 is recommended as the best treatment in acorn processing with tap water. [ABSTRACT FROM AUTHOR]

With the aim of investigation, the effects of oak acorn (OA) (0 or 20 % of diet) and tannin-reducing feed additives (without additive, 10 g polyethylene glycol (PEG)/kg of diet and 0.25 % diet sodium bicarbonate) on performance and liver and kidney tissues of broiler chickens, a total of 480 Ross 308 broiler chicks (average body weight of 41 gram and same male to female ratio) were distributed among 6 experimental treatments (4 replicates of 20 birds) in a 2x3 factorial arrangement and reared for 42 days. The results indicated that application of OA had no significant effect of overall feed conversion ratio, but significantly decreased overall body weight gain. However, sodium bicarbonate improved overall body weight gain, compared to the diet without additive. Feeding birds with OA significantly increased relative weight of gizzard, ileum and caecum at 24 d of age and relative weight of caecum and duodenum at 42 d of age. On d 24, more sever cellular congestion was observed in liver tissue of OA fed birds, but on d 42, the number of liver fat vacuole was less in these birds. Feeding with OA increased diameter of renal corpuscle. In conclusion, dietary inclusion of 20% OA had no significant effects on feed conversion ratio and liver as well as kidney tissue of broilers, but because of significant reduction in overall body weight gain and production efficiency factor, this level is not recommended. However, inclusion of additives did not prevent this reduction. [ABSTRACT FROM AUTHOR]

Today, the use of oak as a replacement feed in poultry diets is well documented. However, oak contains polyphenol compounds (tannins) as antinutrient factors resulted in limited usage in the poultry rations. Generally, consumption of feeds containing tannin could affect gene expression level of immune system. Therefore, the aim of this study was to investigate the effect of different levels of oak acorn on the expression of interferon-γ (IFN-γ), interleukin-2 (IL-2) and interleukin-13 (IL-13) genes in the bursa Fabricius tissue of broiler chickens. For this purpose, broiler chickens were fed with diets containing 0 (control), 15% and 20% oak acorn in 6 weeks experimental period. Total RNA was extracted from bursa Fabricius tissue of 6 chickens for each treatment (18 broiler chickens) on day 42. To investigate the expression of IL-2, IL-13 and IFN-γgenes, their expressions were normalized with β-actin gene as a reference gene. REST, 2009, V2.0.13 software was used for analysis of gene expression data. The results showed that the expression levels of IL-2 and IL-13 genes in bursa Fabricius tissue were not significantly different for 15% oak acorn treatment compare to control group, but the mRNA expression levels of IL-2 and IL-13 were significantly lower in 20% of oak acorn in respect to control and 15% oak acorn diets (P < 0.05). However, expression of IFN-γ gene was not observed in any samples of the three treatments. According to the results of this study, it seems that increasing the amount of oak acorn in diet of broiler chicken with increase tannin content most likely could suppress the expression of IL-2 and IL-13 genes in bursa Fabricius tissue.

Oaks cover a vast area of Jordanian forests, and their fruit (named acorns) have good nutritional value. In this study, we investigated the physical, chemical, and nutritional characteristics of the acorns produced by three Jordanian oak species, Quercus aegilops (QA), Quercus infectoria (QI), and Quercus calliprinus (QC). The physicochemical (acorn length, weight; cupule weight, coat weight, cotyledon weight, coat weight percent, cotyledon weight percent and acorn volume) and nutritional quality (protein, fat, fiber, ash, carbohydrate, amino acid, fatty acid and mineral compostions) of the acorns from the three oak species were determined using standard procedures. The acorn of QA showed significantly greater values compared to QC for all physical characteristics assessed while QC exhibited the lowest values; QI presented intermediate values.The chemical composition of the three species showed that fat content varied from 8.18% to 8.99% and the crude fiber and the total carbohydrate content ranged from 3.27% to 3.86% and 76.20% to 81.43%, respectivelyAccording to obtained results, oak acorn can be considered a significant source of protein (9.54% for QC to 10.9% for QA). Oak acorn contained 18 known amino acids (AAs); with total essential amino acids (TEAA) levels in these oak species as 2307.9, 1699.1, and 2262.8 mg/100 g dry weight, respectively. The most abundant essential amino acid found varied between species: in QA it was leucine (446 mg/100 g dry weight), in QC it was arginine (526 mg/100 g dry weight), and in QI it was phenylalanine (395 mg/100 g dry weight). The ratio of TEAA to total amino acids (TAA) was 0.90: 0.50 and 0.79 for QA, QC and QI, respectively, which indicates that QA is the best species in terms of essential amino acid (EAA) proportion. The EAA scores showed that (phenylalanine + tyrosine) and (methionine + cysteine) were the most abundant AAs in oak acorns, while lysine and leucine were the most limited. The ratio of unsaturated fatty acids to saturated fatty acids in the acorn oil ranged from 3.45:1.00 to 3.93:1.00. Therefore, oak acorn oil may be considered healthy for a human diet. The most abundant minerals in decreasing order were K, P, Ca, Cl, S, Fe, and Mn. These results demonstrate that oak acorns from Jordan have great potential to be included in human feeding. [ABSTRACT FROM AUTHOR]

Background and Aims Oaks are the foundation and dominant tree species of most Mediterranean forests. As climate models predict dramatic changes in the Mediterranean basin, a better understanding of the ecophysiology of seed persistence and germination in oaks could help define their regeneration niches. Tunisian oaks occupy distinct geographical areas, which differ in their rainfall and temperature regimes, and are thus a valuable model to investigate relationships between seed traits and species ecological requirements. Methods Seed morphological traits, desiccation sensitivity level, lethal freezing temperature, embryonic axis and cotyledon sugar and lipid composition, and seed and acorn germination rates at various constant temperatures were measured in Quercus canariensis , Q. coccifera , Q. ilex and Q. suber , using seeds sampled in 22 Tunisian woodlands. Key Results Only faint differences were observed for desiccation sensitivity in the oak species studied. By contrast, the species differed significantly in sensitivity to freezing, germination rates at low temperature and base temperature. Quercus ilex and Q. canariensis , which occur at high elevations where frost events are frequent, showed the lowest freezing sensitivity. A significant correlation was found between hexose contents in the embryonic axis and freezing tolerance. Significant interspecific differences in the time for seeds to germinate and the time for the radicle to pierce the pericarp were observed. The ratio of pericarp mass to acorn mass differed significantly among the species and was negatively correlated with the acorn germination rate. Quercus coccifera , which is frequent in warm and arid environments, showed the highest acorn germination rate and synchrony. Conclusions Seed lethal temperature, seed germination time at low temperatures, the ratio of pericarp mass to acorn mass and the embryonic axis hexose content appeared to be key functional traits that may influence the geographical ranges and ecological requirements of Mediterranean oaks in Tunisia. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether the age of broilers can influence their response to tannin-rich diets. A total of 340 one-day-old mixed sex Ross 308 broiler chicks were distributed among five experimental groups with four replicates and 17 birds each in a completely randomized design. A high-tannin feedstuff, Oak acorn, was included into diets (at a level of 25%) and fed to birds at different stages of the rearing period. The control group was fed a corn-based diet (without Oak acorn) for the entirety of the study, while the other four groups were fed diets containing Oak acorn during one of the following periods: starter (d 1 to 21), finisher (d 22 to 42), last five weeks (d 8 to 42), or total period of the experiment (d 1 to 42). We found that performance traits (feed intake, body weight gain and feed conversion ratio) and tibia characteristics were similar among the control group and groups fed Oak acorn during the starter and finisher periods. However, feeding chicks with Oak acorn from 8 to 42 or 1 to 42 d of age significantly reduced overall body weight gain and increased overall feed conversion ratio (P < 0.05). Tibia characteristics were also negatively affected in chicks that received Oak acorn during the last 5 weeks and entire period of the experiment (P < 0.05). In addition, birds fed Oak acorn had higher liver weights at 21 d of age (P < 0.05). In conclusion, broilers response to dietary tannins is influenced by age. Oak acorn could be successfully included in broiler diets during the starter or finisher stages up to 25% without adverse effects on performance and tibia characteristics. In contrast, chronic inclusion of Oak acorn (5 or 6 weeks) decreases growth performance and may have deleterious effect on tibia characteristics.

This study was conducted to determine the amylase gene expression in liver and pancreas tissues of broiler chicks fed with two levels of oak acorn (OA) fruit. A total of 264 broiler chicks were fed a control diet (without oak) and diets containing 15 and 20% OA. At the end of starter and finisher period, 6 birds from each treatment were randomly selected and Tissue samples were taken from their pancreas and liver. REST and SAS software were used to analyze gene expression. The 2004 Bestkeeper software was also used to determine the sustainability of β-Actin gene expression. Results showed that β-Actin gene was not affected by sex, age and experimental treatments. Thus, it was used to normalize the gene expression data. At 21d of age, the level of mRNA of the pancreatic amylase gene was significantly higher in broilers fed with 15% OA compared to the control group (p<0.05). On d 42, significant differences in expression of liver and pancreas amylase gene were not observed (p>0.05). Also, feeding birds with diet containing 20% OA increased the relative weight of pancreas (p<0.05). In conclusion, the results showed that amylase gene expression in birds fed diets containing 15% OA significantly increased at 21d of age. In other cases, genes expression was not influenced by experimental treatments. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effect of oak acorn (Quercus castaneifolia) on performance, small intestine morphology, ileal digestibility of nutrient, carcass and some blood parameters in broiler chicks. A total of fifty hundred four one-d old male chickens (Ross308 strain) with seven treatments and four replicates in each treatment were used. Experimental diets were: control (corn-soybean meal diet), raw oak acorn at the levels of 10 and 20 percent, soaked oak acorn diet containing 10 and 20 percent oak acorn soaked in water for 24h., diets contain 10 and 20 percent of soaked oak acorn soaked in water for 48h with twice water substitution. Experiment lasted from 1 to 42 day of ages. Results showed that body weight, weight gain, feed intake, feed conversion ratio, ileal dry matter and protein digestibility, and small intestine morphology was significantly (P

The effects of raw and sodium hydrogen carbonate-treated oak acorn were evaluated on broiler chicken performance and cecal flora. A total of 340 one-day-old broiler chicks were used in a completely randomized design with five experimental treatments and four replicates with 17 birds each. A corn-based diet served as the control and four treatment groups were diets containing 20 or 25% raw or treated oak acorn. Treatment of the acorn with sodium hydrogen carbonate significantly reduced the amount of total phenols and tannins in the feed (P < 0.05). Though there were no significant differences in body weight gain and final body weight between the control and treatment groups, treated oak acorn yielded greater overall weight gain than raw oak acorn. Feeding treated or raw oak acorn impaired feed conversion ratio relative to the control during the starter phase of the study. However, finisher (22-42 d) and overall (1-42 d) feed conversion ratio were similar between control and other treatments. Birds fed 25% treated oak acorn had significantly better overall feed conversion ratio than those fed raw oak acorn (P < 0.05). The relative weight of pancreas, liver, abdominal fat, as well as Lactobacillus and E. Coli counts, were similar between all treatments at 21 and 42 d of age. In conclusion, raw or treated oak acorn could be included in broiler diets up to 25% without negative effects on their performance. The performance may be improved by treating oak acorn with sodium hydrogen carbonate because of reducing the content of phenolic components.

An experiment was conducted to evaluate the effects of dietary nutrients (protein, methionine, and choline) manipulation on the performance and tibia characteristics of broilers fed diets containing 15% oak acorn. A completely randomized design with five treatments and four replicates of 15 chicks each, was used. One group was fed a diet based on corn (without oak acorn) as control and other four groups were fed diets containing oak acorn with one of the following nutrient manipulation: without nutrient manipulation, high level of methionine (100% more than NRC), high level of CP (10% more than NRC), and addition of 0.2% choline. Starter and finisher diets were fed from one to 21 and 22 to 42 d of age, respectively. The results indicated that group fed diet without nutrient manipulation presented higher feed intake and worse feed conversion ratio (p

Summary: The aim of this experiment was to investigate the effect of dietary oak (Quercus persica) acorn (OA) level on dry matter intake (DMI), apparent nutrient digestibility, nitrogen (N) utilization, ruminal fermentation, protozoa population and urinary purine derivatives (PD) during the last 60 days of goat pregnancy. Twenty‐four multiparous pregnant goats (41.7 ± 2.3 kg BW) were assigned to one of three experimental diets consisted of control diet (C, without OA) and diets containing 20 (OA20) or 40 g/100 g of OA (OA40) on a DM basis in a completely randomized block design. Goats fed OA40 had lower DMI (p < .01), DM (p < .01), OM (p < .01) and NDF (p < .05) digestibility, ruminal NH3‐N concentration (p < .01), N intake (p < .01) and N retention (p < .01). Crude protein digestibility and ruminal acetate and total volatile fatty acid (VFA) concentration were lower in animals fed OA‐contained diets (p < .01), whereas ruminal propionate concentration was higher in goats fed the C diet (p < .01). Animals fed OA40 had higher faecal N excretion and lower urinary N excretion (p < .01). Urinary PD was lower in goats fed diets containing OA in relation to those fed the C diet (p < .01). Total protozoa population decreased linearly with increasing OA level in the diet (p < .05). These results suggest that feeding OA, especially high level, has negative impacts on DMI, nutrient digestibility, VFA concentration, N retention and urinary PD excretion that may have adverse effects on metabolism and performance of pregnant goats. [ABSTRACT FROM AUTHOR]

Using a completely randomized design, a total of 360 one-day-old male and female broiler chicks were allocated to 6 experimental diets with four replicates (15 birds each), to evaluate the effects of raw or treated oak acorn (OA) on the performance and tibia characteristics of broilers. First diet was a corn-based diet (without OA) as the control, while other 5 diets contained 150 g/kg OA (raw or treated with distilled water, acetic acid, sodium hydrogen carbonate (Alkali) and traditional method). Birds were given starter and finisher diets from 1 to 21 and 22 to 42 d of age, respectively. The results indicated that all treatment methods significantly reduced the content of phenolic compounds. Dietary inclusion of raw OA had no deleterious effect on performance and tibia characteristics when compared to the control. Treatment with Alkali caused the highest overall body weight gain while traditional method resulted in worse performance compared to the raw OA. In conclusion, 150 g/kg raw OA could be included in broiler diets, without adverse effects on their performance or tibia characteristics. Chemical treatment, particularly using Alkali, has the potential to reduce the content of phenols and maybe improve the nutritional value of OA. [ABSTRACT FROM AUTHOR]

Pure starch has been isolated from different samples: oak acorn, sorghum, and potato using alkali steep and wet-milling procedure. The structure of the extracted starches was analyzed using Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction. Their physicochemical properties (water content, ash content, pH, amylose content, swelling power, and water solubility index) were determined. The FT-IR spectra of isolated native starches have shown the main bands characterizing the starch. For sorghum starch (SS) and oak acorn starch (OAS), X-ray diffractograms exhibited an A-type diffraction pattern, while potato starch (PS) displayed typical B-type pattern. Compared to sorghum and oak acorn, potato starch has shown the highest level of both swelling power and water solubility index. To estimate the color removal quality of the extracted starches, a sorption of a dye named maxilon red GRL has been carried onto them. The results of equilibrium isotherms in batch adsorption process were analyzed according to the Langmuir and Freundlich model. The characteristic parameters were determined for each model. Furthermore, the effect of initial pH and ionic strength on adsorption capacity was considered, and regeneration studies were carried out. [ABSTRACT FROM AUTHOR]

The results of investigation of the tannin content in the oak acorn kernel Quercus cerris, qualitative analysis of tannin and antioxidation effect of ethanol extracts of acorn on porcine lipid (prime steam lard) as a substrate are presented in this paper. Experiments were carried out on kernel samples of the domestic oak acorn, from the location Zaglavak, near by the town of Bajina Bašta. Tannin content was determined by spectrophotometric procedure using phosphorus Wolframic acid on wave length of 715 nm. Qualitative analysis of tannin included sediment and stain responses as well as tannoform test with formalaldehyde and HCl. Antioxidant effect of ethanol extracts was investigated on fat samples treated at the temperature of 600C in the dark (Schaaloven test). The rate of oxidation was determined by measuring Peroxide value (Pb) and TBA value. The investigated extracts were obtained based on drying of acorn kernel and extracts based on thermal treatment - dry frying of acorn kernel. The obtained results show that dried acorn kernel contains 11.69 % of tannin and thermally treated acorn kernel 8.55%. Qualitative analysis confirmed the presence of gallic acid (pyrogallic, hydrolysing) tannins based on positive general sediment and stain responses on tannins. Ethanol extracts demonstrate antioxidation traits on porcine lipids in trial conditions. Synergistic effect of citric acid with primary anti oxidant was not proved. Thermal treatment of acorn kernel does not reduce the antioxidation activity of extracts.

Background and Aims Dominant tree species in northern temperate forests, for example oak and beech, produce desiccation-sensitive seeds. Despite the potentially major influence of this functional trait on the regeneration and distribution of species under climate change, little is currently known about the ecological determinants of the persistence of desiccation-sensitive seeds in transient soil seed banks. Knowing which key climatic and microsite factors favour seed survival will help define the regeneration niche for species whose seeds display extreme sensitivity to environmental stress Methods Using the Mediterranean Holm oak (Quercus ilex) forest as a model system, an in situ time-course monitoring of seed water status and viability was performed during the unfavourable winter season in two years with contrasting rainfall, at an instrumented site with detailed climate records. In parallel, the characteristics of the microhabitat and their influence on the post-winter water status and viability of seeds were investigated in a regional survey of 33 woodlands representative of the French distribution of the species. Key Results Time-course monitoring of seed water status in natural conditions confirmed that in situ desiccation is the main abiotic cause of mortality in winter. Critical water contents could be reached in a few days during drought spells. Seed dehydration rates were satisfactorily estimated using integrative climate proxies including vapour pressure deficit and potential evapotranspiration. Seed water status was therefore determined by the balance between water uptake after a rainfall event and water loss during dry periods. Structural equation modelling of microhabitat factors highlighted the major influence of canopy openness and resulting incident radiation on the ground. Conclusions This study provides part of the knowledge required to implement species distribution models which incorporate their regeneration niche. It is an important step forward in evaluating the ecological consequences of increasing winter drought and environmental filtering due to climate change on the regeneration of the most dominant Mediterranean tree species [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this study were to evaluate the effect of oak fruit (Quercus persica) in the diet of sheep with and without polyethylene glycol (PEG) on nutrients digestibility, rumen fermentation parameters, protozoal count and microbial protein supply. In Exp. 1, five fistulated mature male sheep were used in a 5×5 Latin square design, with 5 dietary treatments arranged in a 2×2+1 factorial: (1) control as a basal diet; (2) control plus 10% oak acorn (OA); (3) control plus 30% OA; (4) control plus 10% OA with 100g PEG; and (5) control plus 30% OA with 100g PEG. Incorporation of OA decreased digestible organic matter (DOM), digestible crude protein (DCP) and digestible neutral detergent fiber (DNDF) and the lowest values were observed at the level of 30% OA. However, administration of PEG to the diets overcame deleterious effect of acorn on these parameters, significantly (P <0.01). With the addition of OA a noticeable decrease in ammonia and TVFA concentration was observed and adding PEG to the diets increased these values even higher than those of control (P <0.01). Incorporation of acorn to the diets lowered urinary purine derivatives (PD) and urinary, retained and absorbed nitrogen and increased fecal and endogenous nitrogen (P <0.01). Meanwhile, addition of PEG increased PD and urinary, retained and absorbed nitrogen and decreased fecal and endogenous nitrogen. Total protozoa content was affected in somewhat by OA and PEG supplementation. Isotricha, dasytricha and, diplodinium contents did not differ due to inclusion of OA, however, the trend for entodinium and ophryoscolex was to be decreased (P <0.05). There was a significant effect on individual genera of protozoa following addition of PEG to the diets. Cellulolytic and proteolytic bacteria were not influenced by incorporation of OA but the trend was in decreasing manor. In Exp. 2, in vitro gas production was conducted to evaluate kinetics of gas produced by diets. The parameter “A” did not differ among experimental treatments. Half-time of gas production in control group was higher than that of other treatments. Methane production from diets containing OA and PEG were lower than that of control group. In conclusion, supplementation of OA with PEG may be a practical approach to overcome detrimental effects of tannins in this feedstuff. [Copyright &y& Elsevier]

The potential nutritive values of acorns of Quercus suber, Quercus branti, Quercus coccifera, Quercus cerris and Quercus infectoria were estimated by chemical composition and in vitro gas production technique. Acorns collected at least 10 different trees in three experimental plots. There were significant (P<0.001) differences in the chemical composition among acorns obtained from different oak species. Crude protein (CP) contents of acorns ranged from 25.48 to 61.94 g/kg dry matter (DM). Neutral detergent fiber (NDF) contents ranged from 231.4 to 326.3 g/kg DM. Acid detergent fiber (ADF) contents ranged from 155.9 to 215.4 g/kg DM. Condensed tannin (CT) contents ranged from 7.2 to 26.7 g/kg DM. Starch contents ranged from 600.0 to 681.5 g/kg DM. Polyethylene glycol (PEG) addition significantly (P<0.001) increased the gas production and some estimated parameters of oak acorns. Although there is no significant (P>0.5) differences in the potential gas production of acorn among oak species when incubated in the absence of PEG, there is significant (P<0.001) differences in the potential gas production of acorn among oak species when incubated in the presence of PEG. Although the estimated organic matter (OMD) and metabolisable (ME) contents of acorn for Q. suber and Q. infectoria were significantly (P<0.001) higher than those for Q. branti, Q. coccifera and Q. cerris when incubated in the absence of PEG, the estimated OMD and ME contents of acorn for Quercus cerris and Q. infectoria were significantly lower than those for Q. suber, Q. branti and Q. coccifera when incubated in the presence of PEG. The improvement in gas production, OMD and ME in the presence of PEG emphasizes the negative effect of tannins on digestibility. As a conclusion, oak acorns have potential nutritive values for ruminant animals such as sheep and goat since acorns have high starch, OMD and ME but low level of CT contents. However these results obtained in the current study should be supported by in vivo feeding experiments. [ABSTRACT FROM AUTHOR]

Oak acorn has been studied as an alternative energy source, replacing some grain in rabbit, broiler and sheep concentrate diets. However, the impact of oak acorn supplementation on diet utilisation by goats has not been studied. Such research would be useful in the Mediterranean mountainous areas because of the availability of oak acorn in bulk (October-January) and their use in the smallholder farming system goats. This study examined the effect of replacing barley grain with cork oak acorn (Quercus Suber L.) on apparent digestibility in vivo, nitrogen (N) balance and growth of goat kids. Voluntary intake of acorn was studied. Ten Boer kids ( 26.5 ± 0.5 kg ) were individually housed in metabolism cages and were randomly divided into two equal groups. Kids in each group received individually 500 g oat hay and 600 g of concentrate containing barley grain (control diet) or oak acorn (experimental diet). The digestibility and growth experiment lasted 60 days. In the following 3 weeks, voluntary intake of acorn containing concentrate was measured on kids receiving experimental diet. Digestibility coefficients of dietary constituents (DM, OM, and CP) were reduced (P<0.001) as a result of acorn substitution for barley. Nitrogen retention (g/day) was positive for acorn diet (4.94 g) but lower (P<0.001) than for control diet (8.74). No differences (P>0.05) in CF digestibility and daily gain were observed between the two groups of kids. Voluntary intake of acorn containing concentrate reached 1400 g/day without any observable toxicity sign. In conclusion, complete substitution of barley grain with cork oak acorn did not affect performance of growing kids. This alternative could decrease the cost of animal origin products. [ABSTRACT FROM AUTHOR]