Studies on Filariasis in Kinmen (Quemoy) Islands, Republic of China

Fan,P.C.,Wang,Y.C.,Liu,J.C.,Lo,H.S.,Hsu,Y.P.,Yen,C.H.,Lin,C.C.,Hsu,S.T. INSTITUTE OF TROPICAL MEDICINE YONSEI UNIVERSITY 1974 YONSEI REPORTS ON TROPICAL MEDICINE Vol.5 No.1

1972年 7月 1日부터 1973年 6月 30日까지 1年間 中華民國 臺?省 金門鳥에서 絲狀 症에 關한 調査硏究를 實施한 바 다음과 같은 結果를 얻었다. 1. 金門鳥 55村落에 居住하는 20,018 住民을 對象으로 調査한 바 血中 microfilariae (mf.) 兩性率은 8.8%였고 血液 20立方mm當 mf농도는 16.2였으며 絲狀 感染으로 因 臨床例 는 19.2%였다. 金門鳥 駐屯 軍人 2,428名에서 mf.양성율은 0.1%, mf. 감염농도는 20立方mm當 26.3이었으며 臨床例는 없었다. mf.感染濃度 및 臨床例에 있어 확실히 女性보다는 男性에서 高率을 보였으나 mf.陽性率은 兩性間에 差異가 없었다. mf.陽性率과 臨床例는 年齡의 增加와 一致하였으나 mf. 감렴농도는 年齡의 증가와 無關하였다. 2. 金文鳥 駐屯 軍人에 있어 주둔 其間과 絲狀 感染과는 關係가 없었으며 駐屯基地와 村落과의 距離와도 無關하였다. 軍人들은 모기에 물리지 않도록 잘 保護되어 있었고 주둔지역은 完全히 住民들과 격리되어 있었다. 3. 51村落으로부터의 血液檢査를 받은 1,470名의 絲狀 感染陽性者 中에서 臨床病勢르 보인 例는 19.2%였으며 女性보다는 男性에서 約 5倍가 많았다. 男性에 있어서의 大部分의 臨床例는 生殖器에 症狀을 보였는데 其中 10%는 象皮症을 가진 例는 2名뿐이었다. 4. 43村落의 家屋內에서 잡힌 모기는 4屬 14種(Culex 10種, Aedes 2種, Anopheles 1種, Armigeres 1種)이었으며 이들中 Cules P. fatigans와 Armigeres subalbatus가 大部分이었으나 其他 12種은 매우 적었다. Culcx mimesticus, C. (L) vorax, C. fuscocephala 및 Acdes nocturnus등 의 4新種은 처음으로 發見되었다. Culex p.fatigans는 現存「반크롭트」 絲狀 만을 옮기는 媒介昆 으로 알려져 있다. 治療前 8個 村落으로부터 잡은 438마리의 Culex p. fatigans에서 幼 을 內包하고 있는 모기는 1마리 平均 5.9마리의 絲狀 幼 을 갖고 있는 셈이었으며 全體 感染率은 11.9%, 感染期 幼 을 가진 모기는 10.5%이었다. 上記 8個 村落 住民을 治癒한 後의 樣狀은 治療前과 아주 달라서 모기 1마리當 平均 2.1마리의 幼 을 갖고 있었고 全體感染率은 2.2%, 感染期幼 內包率은 0.09%였다. 平均 pH가 7.4(6.4∼8.0)인 8個處의 모기 産卵場所에서 잡힌 모기 幼 은 모두 11種이었다. 有機燐劑의 一種인 Sumithion을 1平方m當 0.2gm의 농도로 모기 産卵場所 水面에 撒布하였던바 모든 모기 幼 에 對한 殺 果가 좋았다. 5. 總 1.590名의 絲狀 感染者에게 成人當 總量 5gm의 diethylcarbamazine을 10∼12日 間 服用시켜 보았다. 治療率은 80.6%, mf. 減少率은 96.9%였고 反應率는 67.2%였다. 여러 가지 副作用은 있었으나 一般的으로 輕微하였으며 患者가 참을 수 있었으므로 最高用量으로 投藥했을 경우에도 大部分 거절 하지 않았다. 8個 部落에서 捕獲된 Culex P. fatigans의 絲狀 幼 全體感染率, 感染期幼 內包率 및 感染濃度는 患者治療前에 各各 11.9%, 10.5%, 5.9였는데 治療後에는 2.2%, 0.09%, 2.1로 떨어져서 diethylcarbamazine은 microfilariae에 對한 殺충효果가 높을 뿐 아니라 絲狀충 만延을 組止시키는데 좋은 藥劑라고 思料된다 The present investigation is a serial study on “Filariasis in Kinmen (Quemoy) Islands”, which was performed from July 1, 1972 to June 30, 1973. The results are summarized as follows; 1. Parasitological investigation: Of 20,018 Kinmen Chinese in 55 villages examined, the microfilariae (mf.) rate of 8.8%, mf. density of 16.2 per 20cmm blood and clinical rate 19.2% were found: the corresponding figures for a total of 2,428 military personnel were 0.1%, 29.3 and 0.0% respectively. The mf. density and clinical rate were obviously higher in the males than in the females, but no difference was found for the microfilarial rate. The mf. rate and clinical rate were correspondingly increased with age, but there was no difference in mf. density. 2. Transmission of filariasis: It seems no any relation to the length of stationing of the Chinese troops on Kinmen Islands, and also no relation to the distance between the villages and camps; because the servicemen are well protected from the mosquito bites and bites and the camps are completely isolated, to and off limit to the villagers, though they have common places of entertainment. 3. Clinical investigation: Of 1,470 filarial carriers in 51 villages examined physically, the clinical rate of 19.2% was detected. It was about 5 times higher in males than in females. In the males, most of the cases the trouble in their reproductive organs, and 10% had elephantiasis; but in the females, the lymph nodes enlargement and chyluria were more common, only 2 cases had elephantiasis. The clinical rates increased corresponding with age. 4. Entomological investigation: Fourteen(14) species of 4 genera (10 Culex, 2 Aedes, 1 Anopheles and 1 Armigeres) of household mosquitoes were collected from indoor resting sites of 43 villages on kinmen Islands, in which, Cules P. fatigans and Armigeres subalbatus were the most common species, but the remaining 12 species are faily rare. Four (4) new species: Culex mimeticus, C. (L) vorax, C, fucocephala and Aedes noturnvs were found for the first time. Culex p.fatigans is still the only vector. in transmission of bancroftian filariasis. The infection rate of 11.9%, infective rate of 10.5% and 5.9 filarial larvae per infected mosquito were detected in 438 Culex p. fatigans from 8 villages before treatment. The corresponding figures were much lower in the above same villages after treatment (2.2%, 0.09% and 2.1). Eleven (11) species of moswquito larvae were collected from 8 kinds of breeding sites; where, the pH value of 7.4(ranged 6.4∼8.0) was measured. “Sumithion”is one of the organophosphorous compounds, which was first used on the water surface with the dosage of 0.2gm per square meter.A high insecticidal effect against different species of mosquito larvae was observed. 5. Chemotherapy of filariasis: Of 1.590 filarial carriers scheme, with a total does of 5 gm of diethylcarbamazine per adult case for a period of 10∼12 days schedule was performed. The cure rate of 80.6%, mf. reduction tate of 96.9% and reaction rate of 67.2% were found. Although many kinds of side effects were encountered, they were usually mild or transient and could be tolerated by the patients, thus there was almost no refused to the administration of the drug even if the drug was increased to the maximum dosage. The natural infection rate, infective rate and filarial larval density of Culex P. fatigans in 8 villages were found much higher before control measure (11.9%, 10.5% and 5.9%) than after control (2.2%, 0.09% and 2.1). It showed that diethylcarbamazine is a powerful microfilaricidal drug in eliminating the filarial infection and reducing this transmission.

Effect of Methionine Source and Dietary Crude Protein Level on Growth Performance, Carcass Traits and Nutrient Retention in Chinese Color-feathered Chicks

Xi, P.B.,Yi, G.F.,Lin, Y.C.,Zheng, C.T.,Jiang, Z.Y.,Vazquez-Anon, M.,Song, G.L.,Knight, C.D. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.6

A total of 1,200 LinNan Chinese color-feathered chicks were used to study the effects of methionine source [DL-2-hydroxy-4-methylthio-butanoic acid (HMTBa) or DL-methionine (DLM)] and dietary crude protein (CP) level on growth performance, carcass traits, and whole-body nitrogen and fat retention. The trial was designed as a $2{\times}2$ factorial arrangement, including two CP levels (adequate and low) and two methionine sources (HMTBa and DL-methionine). Diets were formulated for three phases, starter (0-21 d), grower (21-42 d), and finisher (42-63 d). Chicks fed HMTBa had higher daily gain and improved feed efficiency than DLM during the grower phase (p<0.05). A significant two-way interaction was observed for growth performance during the finisher phase and overall (0-63 d). Growth performance was greater for chicks fed HMTBa than DLM on adequate-CP diets (p<0.05), but this was not observed at low-CP level (p>0.05). Chicks fed low-CP diets grew slower, used feed less efficiently during the grower, finisher phase and overall. On d 42, regardless of dietary CP levels, birds fed HMTBa had higher carcass weights, breast and thigh weights than DLM-fed birds (p<0.04). Birds fed low-CP diet had lighter carcass weights and less breast muscle, thigh muscle, and dressing percentage at the end of starter, grower and finisher phases (p<0.05). Whole body composition analyses found that birds fed HMTBa tended to contain more protein and less fat compared to those chicks fed DLM at the end of the starter phase (p<0.10). Low-CP diets increased CP concentration in the whole body at the end of the finisher phase (p = 0.05). HMTBa supplementation increased whole-body N retention rate during the finisher phase and overall (p<0.01), and low-CP diets reduced N intake and whole-body fat retention during the finisher phase and overall (p<0.05). In summary, HMTBa was better than DLM on an equimolar basis for growth performance, carcass traits, and N retention in Chinese color-feathered chicks. Low-CP diets lowered growth performance as well as carcass traits in color-feathered birds, probably due to imbalanced AA profiles.

Effect of Replacing Corn and Wheat Bran With Soyhulls in Lactation Cow Diets on In Situ Digestion Characteristics of Dietary Dry Matter and Fiber and Lactation Performance

Meng, Qingxiang,Lu, Lin,Min, Xiaomei,McKinnon, P.J.,Xiong, Yiqiang Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.12

An in situ digestion trial (Experiment 1) and a lactation trial (Experiment 2) were conducted to determine the effects of replacing corn and wheat bran with soyhulls (SH) in lactating dairy cow diets on the extent and kinetics of digestion of DM and NDF, and lactation performance. In experiment 1, five mixed feeds consisting of mixed concentrate and roughages (50:50 on a DM basis) were formulated on isonitrogenous and isoenergetic bases to produce five levels (0, 25, 50, 75 and 100%) of SH replacement for corn and wheat bran. SH had high in situ digestion (92 and 89% for potentially digestible DM and NDF) and fairly fast digestion rate (7.2 and 6.3 %/h for DM and NDF). Increasing level of SH replacement resulted in increased NDF digestibility (linear, p=0.001-0.04) and similar DM digestibility (beyond 12 h incubation, p=0.10-0.41). As level of SH replacement increased, percentage of slowly digestible fraction (b) of DM increased (linear, p=0.03), percentage of rapidly digestible fraction (a) of DM tended to decrease (linear, p=0.14), and DM digestion lag time tended to be longer (linear, p=0.13). Percentage of potentially digestible fraction (a+b) and digestion rate (c) of slowly digestible fraction of dietary DM remained unaltered (p=0.36-0.90) with increasing SH in the diet. Increasing level of SH for replacing corn and wheat bran in the diet resulted in increases in percentages of b (quadratic, p<0.001), a (linear, p=0.08), a+b (quadratic, p=0.001) and a tendency to increase in c for NDF (linear, p<0.19). It was also observed that there was a satisfactory fit of a non-linear regression model to NDF digestion data ($R^2=0.986-0.998$), but a relatively poor fit of the model to DM digestion data ($R^2=0.915-0.968$). In experiment 2, 42 lactating Holstein cows were used in a randomized complete block design. SH replaced corn and wheat bran in mixed concentrates at 0, 25, and 50%, respectively. These mixed concentrates were mixed with roughages and fed ad libitum as complete diets. Replacing corn and wheat bran with SH at 0, 25 and 50% levels did not influence (p=0.56-0.95) DM intakes (18.4, 18.6, and 18.5 kg/d), milk yields (27.7, 28.4 and 27.6 kg/d), 4% fat-corrected-milk (FCM) yields (26.2, 27.6, and 27.3 kg/d) and percentages of milk protein (3.12, 3.17 and 3.18%), milk lactose (4.69, 4.76 and 4.68%) and SNF (8.50, 8.64, and 8.54%). On the other hand, milk fat percentges linearly increased (3.63, 3.85 and 3.90% for SH replacement rates of 0, 25 and 50% in the diet, p=0.08), while feed costs per kg FCM production were reduced.

Effects of Dietary Nitrogen Sources on Fiber Digestion and Ruminal Fluid Characteristics in Sheep Fed Wheat Straw

Tan, Z.-L.,Lu, D.-X.,Hu, M.,Niu, W.-Y.,Han, C.-Y.,Ren, X.-P.,Na, R.,Lin, S.-L. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.10

Fifteen Inner Mongolian wethers with permanent ruminal and duodenal cannulas were used to study the effects of dietary rumen-undegradable protein (RUP) to rumen-degradable protein (RDP) ratios or protein sources on fiber digestion in the gastrointestinal tract and ruminal fluid characteristics. Fiber digestion and ruminal fermentation were not affected (p>0.05) by dietary RUP to RDP ratios (from 1.54 to 0.72). Soybean meal supplementation improved ruminal digestion. Fish meal supplementation increased (p<0.05) the ruminal degradability of fiber. The different RUP to RDP ratios (from 1.54 to 0.72) did not influence (p>0.05) ruminal fluid pH, but there were differences (p<0.05) in ruminal fluid $NH_3-N$ concentration because of urea replacement. Soybean meal as a dietary protein source decreased (p<0.05) ruminal fluid pH and increased (p<0.05 or p<0.01) $NH_3-N$, acetate, propionate and butyrate concentrations in the rumen. Fish meal as a dietary protein source decreased (p<0.05 or p<0.01) ruminal $NH_3-N$ and acetate concentrations and increased (p<0.05) ruminal propionate concentration. It can be concluded that dietary protein sources have more significant effect on fiber digestion and ruminal fermentation than different dietary RUP to RDP ratios, when the dietary crude protein requirements of growing sheep are satisfied.

<i>ITGB6</i> loss-of-function mutations cause autosomal recessive amelogenesis imperfecta

Wang, Shih-Kai,Choi, Murim,Richardson, Amelia S.,Reid, Bryan M.,Lin, Brent P.,Wang, Susan J.,Kim, Jung-Wook,Simmer, James P.,Hu, Jan C.-C. Oxford University Press 2014 Human Molecular Genetics Vol.23 No.8

<P>Integrins are cell-surface adhesion receptors that bind to extracellular matrices (ECM) and mediate cell–ECM interactions. Some integrins are known to play critical roles in dental enamel formation. We recruited two Hispanic families with generalized hypoplastic amelogenesis imperfecta (AI). Analysis of whole-exome sequences identified three <I>integrin beta 6</I> (<I>ITGB6</I>) mutations responsible for their enamel malformations. The female proband of Family 1 was a compound heterozygote with an <I>ITGB6</I> transition mutation in Exon 4 (g.4545G > A c.427G > A p.Ala143Thr) and an <I>ITGB6</I> transversion mutation in Exon 6 (g.27415T > A c.825T > A p.His275Gln). The male proband of Family 2 was homozygous for an <I>ITGB6</I> transition mutation in Exon 11 (g.73664C > T c.1846C > T p.Arg616*) and hemizygous for a transition mutation in Exon 6 of <I>Nance–Horan Syndrome</I> (<I>NHS</I> Xp22.13; g.355444T > C c.1697T > C p.Met566Thr). These are the first disease-causing <I>ITGB6</I> mutations to be reported. Immunohistochemistry of mouse mandibular incisors localized ITGB6 to the distal membrane of differentiating ameloblasts and pre-ameloblasts, and then ITGB6 appeared to be internalized by secretory stage ameloblasts. ITGB6 expression was strongest in the maturation stage and its localization was associated with ameloblast modulation. Our findings demonstrate that early and late amelogenesis depend upon cell–matrix interactions. Our approach (from knockout mouse phenotype to human disease) demonstrates the power of mouse reverse genetics in mutational analysis of human genetic disorders and attests to the need for a careful dental phenotyping in large-scale knockout mouse projects.</P>

Selection and Crossbreeding in Relation to Plumage Color Inheritance in Three Chinese Egg Type Duck Breeds (Anas Platyrhynchos)

Lin, R.L.,Chen, H.P.,Rouvier, R.,Poivey, J.P. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.8

In China and South East Asia, the duck (common duck) is important in egg production for human consumption. Plumage color is a breed characteristic and of economic importance, together with egg production. Our aim in this study was to investigate the inheritance of plumage color in three Chinese indigenous egg-type duck breeds, Shan Ma (S), Putian White (F) and Putian black (P), and some of their crossbreds. These three breeds have different plumage color and are used in crossbreeding. The crossbred laying ducks $F{\times}(P{\times}S)$ and $F{\times}(S{\times}P)$ showed highly improved laying ability but heterogeneous plumage color. Genotypes at four relevant loci were investigated by studying down color and pattern in ducklings after crossbreeding. $F_1$ ducklings from the matings $F{\times}S$ and $S{\times}F$, $P{\times}S$, and $S{\times}P$ were classified into four classes of plumage color (the Shan Ma plumage color, black, white, or multicolored) over three generations. Parents were selected for the Shan Ma plumage color of their progeny. In the fourth generation, P male and P female ducks were selected according to the frequency of the desired class of plumage color (Shan Ma) of their $F_1$ progeny to obtain the so-called "Brown Putian Ma duck". The Shan Ma duck genotype was identified as having the restricted mallard color pattern ($M^RM^R$), full expression of any of the patterns or colors (CC), no extended black (ee) and no brown dilution D (D). The Putian White genotype was recessive white (cc), no extended black (ee) and no brown dilution D (D). The Putian Black genotype exhibited full expression of extended black (E gene) and no brown dilution (CCEE D [D]). It was shown that $F{\times}S$ and $S{\times}F$ tests should be implemented to eliminate the recessive white c allele in the S line and the dominant extended black E allele in the F line. It was also shown that the Brown Putian Ma obtained from Putian Black, with no extended black genotype (ee), could be used to get rid of the black plumage (E gene) in the crossbred ducks. This could provide a solution for producing 3-way crossbred ducks Putian $White{\times}$(Putian-$Ma{\times}Shan$ Ma) and Putian $White{\times}$(Shan $Ma{\times}Putian$-Ma), with the desired Shan Ma feather color.

Comparisons of In vitro Nitrate Reduction, Methanogenesis, and Fermentation Acid Profile among Rumen Bacterial, Protozoal and Fungal Fractions

Lin, M.,Schaefer, D.M.,Guo, W.S.,Ren, L.P.,Meng, Q.X. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.4

The objectives were to compare the ability of various rumen microbial fractions to reduce nitrate and to assess the effect of nitrate on in vitro fermentation characteristics. Physical and chemical methods were used to differentiate the rumen microbial population into the following fractions: whole rumen fluid (WRF), protozoa (Pr), bacteria (Ba), and fungi (Fu). The three nitrogen substrate treatments were as follows: no supplemental nitrogen source, nitrate or urea, with the latter two being isonitrogenous additions. The results showed that during 24 h incubation, WRF, Pr and Ba fractions had an ability to reduce nitrate, and the rate of nitrate disappearance for the Pr fraction was similar to the WRF fraction, while the Ba fraction needed an adaptation period of 12 h before rapid nitrate disappearance. The WRF fraction had the greatest methane ($CH_4$) production and the Pr fraction had the greatest prevailing $H_2$ concentration (p<0.05). Compared to the urea treatment, nitrate diminished net gas and $CH_4$ production during incubation (p<0.05), and ammonia-N ($NH_3$-N) concentration (p<0.01). Nitrate also increased acetate, decreased propionate and decreased butyrate molar proportions (p<0.05). The Pr fraction had the highest acetate to propionate ratio (p<0.05). The Pr fraction as well as the Ba fraction appears to have an important role in nitrate reduction. Nitrate did not consistently alter total VFA concentration, but it did shift the VFA profile to higher acetate, lower propionate and lower butyrate molar proportions, consistent with less $CH_4$ production by all microbial fractions.

Effect of Genistein on Antioxidative Defence System and Membrane Fluidity in Chick Skeletal Muscle Cells

Jiang, Z.Y.,Jiang, S.Q.,Lin, Y.C.,Ma, X.Y.,Xi, P.B.,Cao, T.,Wang, X.Q. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.8

This study was conducted to investigate the protective effect of genistein on the antioxidative defence system and membrane fluidity in chick skeletal muscle cells after supplementation with 0, 20, 40, and $80{\mu}mol/L$ genistein in $50{\mu}mol/L$ $FeSO_4/H_2O_2$ treated cells for 24 h. Genistein supplementation recovered the decreased activity of total superoxide dismutase induced by $FeSO_4/H_2O_2$, significantly increased glutathione peroxidase activity (p<0.05) and decreased malondialdehyde production (p<0.05). The treatment of 80 mol/L genistein in $FeSO_4/H_2O_2$ treated cells decreased the secretion of creatine kinase (p<0.05). Fluorescence polarization values and microviscosities observed with $FeSO_4/H_2O_2$ treated cells were significantly higher than those observed with no $FeSO_4/H_2O_2$ treated cells. The addition of $80{\mu}mol/L$ genistein improved the increased fluorescence polarization value (p<0.05) caused by $FeSO_4/H_2O_2$ treatment. The microviscosity value was significantly decreased by adding genistein (p<0.05). In conclusion, genistein protected skeletal muscle cells from oxidative damage by improving antioxidative status and membrane fluidity.

Electron-Electron Interactions in a Two-Dimensional Electron Systemin an Al0.15Ga0.85N/GaN Heterostructure Grown on p-Type Si

Jian-Zhe Huang,Li-Hung Lin,Chin-An Chang,Chi-Te Liang,Kuang Yao Chen,Kui-Ming Chen,N. C. Chen,P. H. Chang,Shiou-Shian Han,Zhi-Hao Sun 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.50 No.3

We report on experimental studies of an Al$_{0.15}$Ga$_{0.85}$N/GaN high-electron-mobility transistor structure grown on a $p$-type Si (111) substrate. This structure is compatible with complementary metal-oxide-semiconductor (CMOS) technology and, thus, has great potential device applications. The low-temperature magnetoresistivity shows a parabolic dependence on the applied perpendicular magnetic field. This effect is ascribed to electron-electron interaction (EEI) effects in a weakly-disordered two-dimensional system. Our experimental results agree with the EEI theory when the correction term in the ballistic region has been subtracted.

Effect of Dietary Structural to Nonstructural Carbohydrate Ratio on Rumen Degradability and Digestibility of Fiber Fractions of Wheat Straw in Sheep

Tan, Z.-L.,Lu, D.-X.,Hu, M.,Niu, W.-Y.,Han, C.-Y.,Ren, X.-P.,Na, R.,Lin, S.-L. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.11

The effect of different dietary structural carbohydrate (SC) to nonstructural carbohydrate (NSC) ratios on fiber degradation, digestion, flow, apparent digestibility and rumen fluid characteristics was studied with a design using 18 wethers fitted with permanent rumen and duodenum cannulae. All sheep were divided into six groups randomly, receiving six diets with varying SC to NSC ratios. All diets contained the same proportion of wheat straw and concentrate. The dietary SC to NSC ratios were adjusted by adding cornstarch to the concentrate supplements. The duodenal and fecal flows of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HC) and cellulose (CEL) were estimated using chromium-mordanted wheat straw as a flow marker. The degradation parameters of wheat straw DM, NDF, ADF, HC and CEL were determined by incubating the ground wheat straw in nylon bags in the rumen for different periods of time. There was no effect (p>0.05) of the different dietary SC to NSC ratios on rumen pH or $NH_3$-N, but acetate, propionate and butyrate concentrations were significantly affected (p<0.05 or p<0.01) by dietary SC to NSC ratios in the rumen fluid. When the dietary SC to NSC ratio was 2.86, the highest rumen degradability of wheat straw DM, NDF, ADF and CEL was found, but the highest apparent rumen digestibilities of DM, NDF, ADF, HC and CEL occurred at a 2.64 SC to NSC ratio. However, because of compensatory digestion in the hindgut, the apparent digestibilities of DM, NDF, ADF, HC and CEL were highest when the dietary SC to NSC ratio was 2.40. In conclusion, there is a optimal range of dietary SC to NSC ratios (between 2.86 and 2.40) that is beneficial to maximize wheat straw fiber degradation and apparent digestibility.