Contribution of different rumen microbial groups to gas,short‐chain fatty acid and ammonium production from different diets—an approach in an in vitro fermentation system

In this study, the relative contribution of different microbial groups to ruminal metabolism was investigated for different diets. The rumen microbial cultures included whole rumen fluid, fungi + protozoa, bacteria + protozoa, protozoa and bacteria + fungi and were established by physical and chemical methods. Gas production, short‐chain fatty acid (SCFA) and ammonium production were measured at 24 hr in in vitro incubations using the Hohenheim gas test (HGT) procedure. Seven donor animal diets with different concentrate‐to‐roughage ratios (C:R: 10:90, 30:70, 50:50, 70:30, 70:30BC (BC = NaHCO₃), 90:10 and 90:10BC) and five HGT diets (C:R: 10:90, 30:70, 50:50, 70:30 and 90:10) were formulated. Incubations in the HGT were always based on inoculum from sheep diets with the respective C:R ratio. Gas and ammonium production increased (p < 0.001) as a result of a gradual increase in concentrate proportion of the diets. In general, SCFA production followed the same trend. Whole rumen fluid and bacteria + fungi produced approximately 50% higher gas volume than protozoa and fungi + protozoa fractions, whereas gas production with bacteria + protozoa was at an intermediate level. Coculture of protozoa either with bacteria or with fungi produced more ammonium. Populations without bacteria were characterized by a particularly high acetate/propionate ratio. Although an interaction between microbial group and diet was observed for several variables, no clear direction could be established. Manipulating rumen fluid by selectively suppressing specific rumen microbial groups may be a helpful tool in elucidating their role in nutrient degradation and turnover in vitro.     

Effects of different roughage sources and feeding levels on adipogenesis of ovine adipocytes

The objective of the present study was to conduct an adipogenic evaluation of different roughage sources and feeding levels during ruminant adipocyte differentiation in vitro. Six wether sheep were divided into a timothy hay feeding group (TFG, n = 3) and an Italian ryegrass straw feeding group (IFG, n = 3). The sheep were fed high‐roughage (HR), medium roughage (MR) and low‐roughage (LR) diets in a one‐way layout design each over a 6‐day period. Sheep serum samples collected on the last day of each dietary treatment were added to an adipogenic induction medium for differentiation of preadipocytes derived from sheep subcutaneous adipose tissue. The cytoplasmic lipid accumulations in the TFG serum‐treated preadipocytes were significantly higher than those of the IFG‐serum treated preadipocytes on day 12. Messenger RNA expression of CCAAT/enhancer‐binding protein (C/EBP)‐α, C/EBP‐β, C/EBP‐δ, fatty‐acid‐binding protein (aP2) and stearoyl‐coenzyme A desaturase (SCD) were regulated by each serum treatment. This study shows that different roughage source diets and roughage‐to‐concentrate ratio diets can regulate adipocyte differentiation via ruminant blood composition.     

Effect of tropical browse leaves supplementation on rumen enzymes of sheep and goats fed <Emphasis Type="Italic">Dichanthium annulatum</Emphasis> grass-based diets

In a switch-over experiment, eight male animals, four each of sheep and goats of local breeds with mean body weight of 26. 8 ± 2.0 and 30.0 ± 2.1 kg, were fed Dichanthium annulatum (DA) grass and four browse species viz. Helictris isora, Securengia virosa, Leucaena leucocephala (LL) and Hardwickia binnata (HB) in four feeding trials to assess their supplementary effect on activity of rumen enzymes. The sheep and goats were offered DA grass with individual browse in 75:25 and 50:50 proportions, respectively, for more than 3 months during each feeding trial, and rumen liquor samples were collected twice at 0 and 4 h post feeding after 60 and 90 days of feeding. Glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and glutamate dehydrogenase (GDH) enzymes were determined in the bacteria and protozoa fractions of rumen liquor, while cellulase enzyme activity was measured in mixed rumen liquor. LL and HB had the highest and lowest contents of CP, while fibre contents were lower in early than later browse leaves. Supplementation of browse leaves significantly (P < 0.05) affect the specific activity of GDH enzyme in bacteria fraction of rumen liquor of animal species, while GDH activity was similar in protozoa fraction of rumen liquor of sheep and goats on all DA grass–browse-supplemented diets except DA–HB (42.8 units/mg protein), where activity was significantly (P < 0.05) low. Specific activities of GOT and GPT enzymes in both bacteria and protozoa fractions of rumen liquor differ significantly (P < 0.05) due to supplementation of browse leaves to DA grass. Browse leaves significantly (P < 0.05) affect the cellulase enzyme activity in animal rumen liquor, being highest on DA–LL (193.4) and lowest on DA–HB diet (144.8 μg sugar/mg protein). Goat exhibited higher activities of GOT and GPT than sheep in both bacteria and protozoa fraction of rumen liquor, while cellulase activity was similar between the animal species on the grass–browse leaves diets. Results indicate that browse leaves supplementation affect the enzyme activities of sheep and goats rumen, while the goats rumen liquor had higher activities of GOT, GPT and GDH enzyme than sheep.     

不同加工处理日粮对绵羊瘤胃挥发性脂肪酸的影响

选用3只健康并安装永久性瘤胃瘘管的杂种羯羊,平均体重为24 kg,采用3×3无重复拉丁方试验设计,用3种不同日粮(全混合颗粒料日粮、粉碎精料+铡短粗料日粮和未粉碎精料+铡短粗料日粮)来研究对绵羊瘤胃挥发性脂肪酸(VFA)浓度的影响。结果表明,采食未粉碎精料+铡短粗料日粮绵羊的瘤胃总挥发性脂肪酸(TVFA)浓度显著高于采食全混合颗粒料日粮绵羊(P＜0.05),采食未粉碎精料+铡短粗料及粉碎精料+铡短粗料日粮的绵羊瘤胃丙酸摩尔比显著或极显著高于采食全混合颗粒料日粮绵羊(P＜0.05,P＜0.01),而(戊酸+异戊酸)摩尔比极显著低于全混合颗粒料日粮绵羊(P＜0.01),乙酸/丙酸显著或极显著低于采食全混合颗粒料日粮绵羊(P＜0.05,P＜0.01)。因此,用粉碎精料+铡短粗料或未粉碎精料+铡短粗料日粮饲喂绵羊能改善绵羊瘤胃发酵类型。     

Effects of over-load iron on nutrient digestibility,haemato-biochemistry,rumen fermentation and bacterial communities in sheep

There is a risk of iron overload in grazing livestock. However, the effects on nutrient absorption and rumen function induced by excessive iron have not been well understood. Therefore, the purpose of present study was to investigate the impact of over-load iron on growth performance, nutrient digestibility, blood biochemistry, rumen fermentation and bacterial communities in sheep. Twenty-four German Mutton Merino cross-bred sheep with weight (42.66 ± 2.34 kg BW) were randomly divided into 4 groups, each with 6 replicates and 1 sheep per replicate. The basal diet consisted of 60% Leymus chinensis hay and 40% concentrate. The sheep in 4 groups were fed the basal diets supplemented with 50 (Control), 500 (T1), 1,000 (T2) and 1,500 (T3) mg Fe/kg as ferrous sulphate monohydrate (FeSO₄·H₂O) respectively. And the actual contents of iron in the diet were determined to be 457.68 (control), 816.42 (T1), 1,256.78 (T2) and 1,725.63 (T3) mg/kg respectively. The experiment lasted 62 days including a 7-day metabolism trial. During the whole experiment, the digestibility of dry matter, organic matter, neutral detergent fibre and acid detergent fibre showed a quadratic increase with increasing over-load iron levels (p < .05), and maximum responses were found with 500 mg/kg supplementation. However, the response of total VFA concentration showed a quadratic decrease, as did the concentrations of propionate, butyrate and valerate (p < .05). Serum total iron-binding capacity on day 30 showed a quadratic decrease with the increase in high-dose iron, while the serum iron content increased linearly at day 60 (p < .05). Excessive iron resulted in the change in bacterial communities. An increase in over-load iron linearly decreased the abundance of bacteria in the phylum Bacteroidetes (p < .05), but linearly increased the Firmicutes (p = .037) and Proteobacteria (p = .018). In addition, there was a quadratic effect (p = .003) on the Fibrobacteres, which was higher in the 500 and 1,000 mg/kg Fe-supplemented groups. At the genus level, there were quadratic effects on the abundances of Selenomonas_1 (p = .023) and Ruminococcaceae_UCG-014 (p = .016). Furthermore, feeding of iron linearly increased the relative abundances of Succiniclasticum and Succinivibrionaceae_UCG-002 (p < .05). These results indicate that increasing ferrous sulphate monohydrate in diets had no negative impact on the growth performance, but it changed nutrient digestibility, blood iron parameters, rumen fermentation and bacterial communities in sheep.     

Forage intake and weight gain of ewes is affected by roughage mixes during winter in northeastern China

We studied the effect of dietary roughage species and their combinations on forage intake and growth rate of ewes during winter in a pastoral‐farming area of northeast China. Twenty‐five Northeast crossbred ewes (fine‐wool sheep × Small‐tailed Han sheep) were randomly selected and divided into five groups (G1, G2, G3, G4 and G5). During a 30 day feeding trial, each group of ewes were offered the same basal diet (composed of 0.36 kg chopped maize stalk (10 mm), 0.14 kg corn meal, 0.05 kg soybean meal and 1.2 g NaCl) and one of the five supplementary roughage mixes, namely 100% Leymus chinensis hay (G1), 100% Vigna radiata stalk (G2), L. chinensis hay plus Suaeda glauca (G3), V. radiata stalk plus S. glauca (G4) and L. chinensis hay plus V. radiata stalk and S. glauca (G5). The results showed that roughage mixes had significant influences on daily roughage intake and daily weight gain of ewes. Ewes had greater daily roughage intake when supplemented with three species of roughage compared to the roughage with one species; however, there was no significant difference between G1 and G2, G3 and G4, or between G4 and G5. The average daily gain of ewes was also greater when they were supplemented with the roughage combination of L. chinensis, V. radiata stalk and S. glauca. No difference in average daily weight gain was observed between the G4 and G5 treatments (P > 0.05). The lowest average daily weight gain was observed when the ewes were supplemented with V. radiata stalk alone (G2) (P < 0.05). The results indicated that supplying ewes with various roughages simultaneously in winter could improve their forage intake and average daily weight gain compared to offering the ewes only one type of dietary roughage. Further, feeding roughage supplements containing a diverse mix of roughage species represents one method for increasing roughage utilization in livestock production during winter in the pastoral‐farming areas of northeastern China.     

Effect of dietary supplementation of hemp seed (Cannabis sativa L.) on meat quality and egg fatty acid composition of Japanese quail (Coturnix coturnix japonica)

This study was conducted in two separate experiments. Experiment I was conducted to investigate the effects of hemp seed (HS) on meat quality traits, and experiment II was designed to determine egg fatty acid (FA) composition in Japanese quail (Coturnix coturnix japonica). In experiment I and experiment II treatments, groups were as follows: (i) control (not included HS0), (ii) 5% HS inclusion to diets, (iii) 10% HS inclusion to diets and (iv) 20% HS inclusion to diets. In experiment I, a total of 192 7‐day‐old‐quail were fed with HS diets for 5 weeks, and end of the experiment I, a total of 64 quail (16 each) slaughtered and meat samples were analysed for meat colour, pH, cooking and thawing loss and FA composition. In experiment II, a total of 120 8‐week‐old laying quail were fed with experimental diets for 6 weeks and egg FA composition were determined. Breast meat cooking loss was significantly lower in 20% supplemented group (p < 0.01). Hemp seed inclusion to diets caused a linear and cubic increase in redness (a*) of hip meat (p < 0.01). Palmitoleic and oleic FAs were decreased with HS addition in breast meat (p < 0.05); however, linoleic and linolenic acid contents of meat were linearly increased (p < 0.01). In experiment II, the linoleic and linolenic FA contents of egg samples were linearly increased with increasing the dietary HS ratio (p < 0.01). Hemp seed addition was provided lower palmitoleic and oleic FAs in quail eggs (p < 0.05). In conclusion, HS supplementation to quail diets may increase quail meat redness and meat and egg yolk omega‐3 FA content and decrease cooking loss of quail meats.     

The effect of leucaena hay as a source of effective fibre and nutrients in diets with forage palm for finishing sheep in semi-arid regions

The present study was conducted to evaluate the intake, digestibility and nitrogen balance of diets for finishing sheep, containing leucaena hay as a source of effective fibre and forage palm. Twenty-one male sheep were used in a randomized block design with three treatments, represented by total diets, where the forage was leucaena hay and forage palm in natura in proportions 350:650, 450:550 and 550:450 g/kg respectively. For the pH and NH₃-N in the ruminal fluid, and urea in the blood serum, plots split in time were adopted. Dry matter and nutrient digestibility, and the nitrogen balance were not influenced (p > .05) by the diets. The neutral detergent fibre digestibility decreased (p < .05) as the proportions of leucaena hay in the diets increased. The pH and NH₃-N were suitable for ruminal fermentation, and blood urea was maintained under normal physiological conditions for sheep. Combining 350 to 550 g/kg of leucaena hay with 450 to 650 g/kg of forage palm in total diets with a forage:concentrate ratio of 60:40 in late-maturing sheep meets the nutritional requirements for daily gain 200 g, characterizing leucaena hay as important source of effective fibre and nutrients in diets.     

The supplementary value of different parts of enset (Ensete ventricosum) to sheep fed wheat straw and Desmodium intortum hay

A study which included growth and digestibility experiments was conducted to evaluate the feeding value of a) enset pseudostem, b) enset corm or c) enset mixture (containing equal amounts of pseudostem, corm and enset leaf on a DM basis) as a supplement to a basal diet of wheat straw fed ad libitum and restricted amounts of Desmodium intortum (Desmodium) hay to sheep. During the 71-day growth experiment, 18 one-year-old male sheep of indigenous breed with mean body weight (BW) of 20.2 (± 0.43) kg were randomly assigned to the three treatments. In the digestibility experiment, three male sheep with mean BW of 19.5 (± 1.06) kg were assigned to each treatment. Sheep supplemented with enset mixture consumed more (P < 0.001) wheat straw DM (335 g/day) than those supplemented with pseudostem (295 g/day). No differences were found in total dry matter (DM) and organic matter (OM) intake between diets supplemented with pseudostem, corm and enset mixture. Total nitrogen (N) intake (g/day) was higher (P = 0.0073) in sheep fed the diet with enset mixture (12.2) followed by corm (11.3) and pseudostem (10.7). The apparent digestibility of DM was higher (P < 0.001) in pseudostem (0.53) followed by corm (0.46) and enset mixture (0.41) supplemented sheep. Organic matter, neutral detergent fiber and N digestibility were similar among treatments. The amount of N lost in urine and faeces and the N-retention was similar among treatments. There were no differences in gain/day in sheep fed diets with pseudostem (29.3 g), corm (27.0 g) and enset mixture (36.5 g). It is concluded that supplementation of a wheat straw/Desmodium diet with enset fractions could be used equally at least to maintain body weight during the dry season.     

Effects of feeding sorghum-sudan, alfalfa hay and fresh alfalfa with concentrate on intake, first compartment stomach characteristics, digestibility, nitrogen balance and energy metabolism in alpacas (Lama pacos) at low altitude

The objective was to evaluate effects of feeding sorghum-sudan- or alfalfa-based diets on intake, first compartment stomach characteristics, digestibility, nitrogen balance and energy metabolism in alpacas at low altitude (793 m). Six mature alpacas (42 ± 2.3 kg of body weight) were used in a replicated 3 × 3 Latin square experiment. The treatments were: sorghum-sudan diets (SSD), alfalfa hay diets (AHD) and fresh alfalfa diets (FAD), respectively. Alpacas were housed in metabolism crates and diets were fed for 21 days with 11 d of adaptation and 10 d of sampling. Alpaca was supplemented concentrate with 160 g per alpaca per day and forages were fed at 12 h intervals with water provided ad libitum. First compartment stomach pH and ammonia N were unaffected by forage source, whereas total VFA concentration was different between diets, with the least for FAD (46.8 mM), followed by AHD (51.8 mM) and the highest for SSD (56.1 mM). Ratio of acetate to propionate was greater for AHD and SSD than for FAD diets. The molar proportion of acetate decreased, whereas the molar proportion of propionate increased for FAD relative to AHD and SSD. Redox potential was lower for SSD than for FAD. Surface tension was greater for FAD than for SSD and AHD. Osmolality was lower for FAD than for SSD and AHD. First compartment pressure and methane production tended to be higher for FAD than for SSD (P < 0.06) and AHD (P < 0.07). Digestibilities of DM, OM and EE were not different between diets. However, the digestibility of CP was lower for AHD relative to SSD and FAD. Digestibilities of NDF and ADF were greater for SSD than for AHD and FAD. Intakes of gross energy (GE) and N were greater for AHD than for FAD and SSD. Digestible energy (DE) was the highest in AHD followed by SSD and FAD. Metablizable energy (ME) was different with the lowest for FAD (3.9 MJ/day), followed by SSD (5.4 MJ/day) and the highest for AHD (8.1 MJ/day). Energy retained was followed the same trend as ME. The results demonstrate variable responses of alpacas to feeding sorghum-sudan or alfalfa diets in terms of dry matter intake, first compartment stomach characteristics, digestibility, nitrogen balance and energy metabolism at low altitude.     

Effect of urea supplementation on performance and safety in diets of Dorper crossbred sheep

This study was conducted to evaluate the efficacy and safety of dietary urea in sheep rations having a 50:50 concentrate:roughage ratio. Sixty‐four Dorper × thin‐tailed Han crossbred ram lambs with an average body weight of 30.8 (±0.02) kg were randomly divided into four groups of 16 sheep each, and each group was fed one of the following diets: a basal diet (CON), or CON supplemented with 0.5% (0.5UTM), 1.5% (1.5UTM) or 2.5% (2.5UTM) urea. Growth performance, carcass characteristics, non‐carcass offals, meat quality and peptic tissue lesions were assayed. The average daily weight gains for CON, 0.5UTM, 1.5UTM and 2.5UTM were 216, 218, 200 and 170 g, respectively, with the CON and 0.5UTM groups higher than 2.5UTM group (p < 0.05). Sheep from the 2.5UTM treatment had a significantly lower dry matter intake (1.29 kg/day) than those from the CON and 0.5UTM treatments (1.42 and 1.43 kg/day, p < 0.05), and the feed conversion ratio in the 2.5UTM group was the highest (p < 0.05). Carcass characteristics, including shrunk body weight, empty body weight, hot carcass weight, dress percentage, and the absolute or relative weight (% body weight) of heart, liver, spleen, lung and kidney, were not altered by the treatments (p > 0.05). The muscular pH of 2.5UTM was higher than that of CON (5.68 vs. 5.52, p < 0.05), and shear force in 0.5UTM was lower compared with CON and 2.5UTM (p < 0.05). The anatomical structure lesions in kidneys became more serious with the increasing dietary urea concentrations, with the 2.5UTM animals showing the most severe lesions compared with CON animals. Therefore, supplementary urea as a non‐protein nitrogen source for sheep should not exceed 1.5% of ration having a 50:50 concentrate:roughage ratio to ensure efficacy and safety.     

牛羊养殖中前胃疾病鉴别诊断方法

牛羊都是反刍动物,它们拥有4个胃,分别是瘤胃、网胃、瓣胃和真胃。前3个胃统称为前胃,在前胃中有大量的可以分解和消化饲料中粗纤维的细菌,是牛羊以粗饲料作为主要食物的原因之一。很多牛羊非常容易出现前胃疾病,饲养人员要掌握牛羊前胃疾病的预防办法和治疗措施。     

Pharmacokinetics of subcutaneously administered doramectin in alpacas

The objective of this research was to evaluate comparative pharmacokinetics of doramectin in alpacas, after subcutaneous administration of 0.2 mg/kg dose. Six healthy adult alpacas, mean age of 5 years ± 1, (three female and three gelded males) of mean bodyweight of 62 kg ± 16 kg with an average body condition scored 2.8 ± 1 out of five, were used in this study. Serial blood samples were collected from the jugular vein before the administration until day 21 afterwards to establish the pharmacokinetics of doramectin after its subcutaneous administration at 0.2 mg/kg dose. The blood samples were analysed using high-performance liquid chromatography (HPLC), fluorescence detection method with precolumn derivatisation, validated for alpacas. The pharmacokinetic parameters were calculated using a noncompartmental model, and results showed Cmax (6.05 ± 5.34 ng/ml), Tmax (3.83 ± 2.48 days), AUC (62.12 ± 18.86 ng/ml × d), terminal half-life (6.2 ± 4.9 days) and MRT (11.56 ± 4.43 days). The results of this study showed that the Cmax and AUC were much lower than in cattle and sheep at the same dosage. Tmax remained similar to cattle and sheep. This study presents valuable information about pharmacokinetics of doramectin in alpacas, which can be utilised in its future efficacy studies.     

Behavior of sheep fed babassu cake (Orbygnia speciosa) as a substitution for elephant grass silage

This study aimed to evaluate the behavior of sheep fed babassu cake as a substitution for elephant grass silage. The experiment was conducted at the Federal Rural University of Amazonia (Universidade Federal Rural da Amazônia ‐ UFRA), Brazil, using 45 sheep housed in individual stalls, with unlimited access to feed and distributed in a completely randomized design with five treatments (0, 12.5, 25, 37.5 and 50% inclusion of babassu cake) and nine replications. All of the treatments contained a roughage‐to‐concentrate ratio of 40:60. No differences were observed in the time spent feeding (P > 0.05), regardless of the source of roughage used. However, there was a reduction in the time spent in rumination (P < 0.05) and an increase in time spent idling (P < 0.05) when babassu cake was included in the diet. Although there was a reduction in the time spent chewing the ruminal bolus (P < 0.05), the total daily chewing time was the same for all animals (P > 0.05). However, the sheep fed babassu cake showed higher feeding and rumination efficiency (P < 0.05). Therefore, the substitution of elephant grass silage with babassu cake can be performed at up to 50% without compromising the total time spent eating and chewing, which allows increased feeding and rumination efficiency.     

Alpacas fed calcium propionate seem to moderate their energy intake

Alpacas have evolved digestive and metabolic adaptations that enable them to survive in environments where the available feed varies in nutritional quality. Alpacas are thought to derive glucose from the deamination of amino acids in the liver, rather than via the conversion of propionate like true ruminants. Because fibre growth is dependent on the availability of absorbed amino acids, alpacas using amino acids as a source of energy should leave less amino acids available for fibre growth. If alpacas were to obtain glucose from a source of propionate, such as calcium propionate, the dependence on amino acids would be reduced leaving more available for fibre growth. Calcium propionate was added to the ration fed to 32 alpaca wethers, and fibre production was measured to monitor important fibre attributes in response to calcium propionate. Although the diets supplemented with calcium propionate should have provided more energy than the diets without calcium propionate, the metabolisable energy intake of all animals was similar (p = 0.278). It seems that rather than sparing amino acids, the alpacas regulated their energy intake and refused to consume the additional energy offered as calcium propionate. Consequently, they produced less fibre, and the diameter of their fibre was smaller than those alpacas that were not fed calcium propionate. It seems that alpacas rely on their digestive and metabolic adaptations to efficiently obtain and conserve energy for their survival.     

Influence of various concentrate‐to‐roughage ratios on dietary intake and nutrient digestibilities of weanling horses

The objective of this study was to compare the feed intake and the apparent digestibilities of three different diets varying in concentrate‐to‐roughage ratios in weanling horses (n = 24) at 5 and 8 months of age. Horses were stratified by breed, gender, birth date and body weight and assigned to one of three dietary treatments containing the following concentrate‐to‐roughage ratios on an as‐fed basis: 70:30 (High Con), 50:50 (Equal) and 30:70 (Low Con). All horses were fed their respective diets for a 10‐day adaptation period and a 4‐day collection period at 5 and 8 months. There were no differences in BW or daily feed intake among treatments during both trials. The horses consuming Low Con had a greater amount of faecal output than High Con at both 5 and 8 months (p < 0.01). At 5 months, High Con had the highest crude protein (CP) digestibility (p < 0.05). At 8 months, High Con had a higher CP digestibility than Low Con (p < 0.01) and tended to be higher than Equal (p = 0.07). Acid detergent fibre (ADF) digestibility did not differ among treatments; however, horses fed the Low Con tended to digest a higher percentage of neutral detergent fibre (NDF) than both the Equal and High Con treatments (p = 0.09). Horses in the High Con treatment tended to digest a higher percentage of energy than those in the Low Con treatment (p = 0.06). Weanlings seem to digest protein more thoroughly when fed high‐concentrate diets and may digest fibre more efficiently when fed diets higher in fibre.     

Effect of increasing levels of wasted date palm on digestion,rumen fermentation and microbial protein synthesis in sheep

This study was conducted to evaluate the effects of increasing levels of wasted date (WD) in sheep (initial body weight 50 ± 2.3 kg) diets on apparent diet digestibility, rumen fermentation and microbial protein synthesis. The experimental diets contained 0 (0 WD), 9% (9 WD), 18% (18 WD) or 27% (27 WD) of wasted dates. These diets were evaluated through a 4 × 4 Latin square design with four 28‐day periods. Sheep were individually housed in metabolic cages and were fed diets ad libitum. To keep the diets isoenergetic and isonitrogenous, increasing partial replacement of WD for barley grain was used with increasing levels of soya bean meal. Increasing the amount of WD in diets of sheep did not influence (p > 0.05) diet intake and digestibility of nutrients. Inclusion of WD in diets of sheep did not affect (p > 0.05) ruminal pH but decreased (p < 0.05) NH₃‐N concentration and blood urea nitrogen. Also there was no effect (p > 0.05) of the WD provision on N intake and faecal N loss of experimental animals, but urinary nitrogen excretion and retained nitrogen were affected (p < 0.05) by dietary treatments. Purine derivatives and microbial protein synthesis increased (p < 0.05) linearly with the level of WD in the diet. In conclusion, the increase in microbial protein synthesis and concomitant reduction in ruminal NH₃‐N concentration and blood urea nitrogen in response to wasted date supply suggest improved efficiency of ruminal nitrogen metabolism without adverse effects on fermentation characteristics and animal performance.     

脲酶抑制剂和粗料类型对育肥羊生长性能及内脏器官的影响

选择小尾寒羊母羔羊24只，体重20.5 kg左右，采用2×2析因试验设计。秸秆型日粮的粗料组成是玉米秸秆，苜蓿＋秸秆型日粮的粗料组成是苜蓿和玉米秸秆，每种粗料日粮设添加与不加20 mg/kg脲酶抑制剂共2个水平。进行90 d育肥试验，以研究在不同类型粗料日粮中添加脲酶抑制剂对育肥羊生长性能和内脏器官的影响。结果表明：①在不同粗料类型日粮中，添加脲酶抑制剂均能提高育肥羊的日增重，苜蓿＋秸秆型日粮较秸秆型日粮的育肥羊有较高的日增重。②粗料类型及脲酶抑制剂对试验羊的内脏器官没有影响。③日粮中添加苜蓿较添加脲酶抑制剂更能提高养羊者的经济效益。     

Chemical composition of alfalfa silage with waste date and its feeding effect on ruminal fermentation characteristics and microbial protein synthesis in sheep

This study was conducted to evaluate the effect of feeding ensiled alfalfa with waste date on ruminal fermentation characteristics, microbial protein synthesis, protozoa population and blood parameters in sheep. Eight rams were used in a 2 × 2 change over design. Each experimental period consisted of 21 days including 16 days for adaptation and 5 days for sampling. For ensiling, fresh alfalfa (Medicago sativa L.) with different levels of waste date (Phoenix dactylifera L.) were mixed together and ensiled in 100‐l containers for 45 days. Chemical composition of silages such as dry matter (DM), crude protein, NH₃‐N, organic matter, NDF, ADF and pH were determined. Then, it was used as 30% (DM basis) in diets. The experimental diets were as follows: (i) control (diet containing alfalfa silage without waste date), (ii) diet containing alfalfa silage with 5 g waste date/95 g DM, (iii) diet containing alfalfa silage with 10 g waste date/90 g DM, and (iv) diet containing alfalfa silage with 15 g waste date/85 g DM. The results of this experiment showed that adding waste date to alfalfa during ensiling, improved silage quality, DM and energy level. Total protozoa population and all of holotrich, cellulolytic and entodinia in rumen fluid were increased linearly by increasing the level of waste date. Nitrogen (N) intake, urinary N excretion and nitrogen retention were affected by dietary treatments. Also, allantoin, uric acid, total purine derivatives, microbial protein synthesis, cholesterol level and blood urea nitrogen were significantly different. In conclusion, direct ensilage of alfalfa can be attained by mixing 15 g waste date/85 g DM and positive associative effects such as increased metabolizable energy (ME) and silage quality occurred.     

Effects of enzymatically treated Artemisia annua L. on growth performance and some blood parameters of broilers exposed to heat stress

To evaluate the effects of enzymatically treated Artemisia annua L. (EA) on growth performance and some blood parameters of broilers exposed to heat stress (HS), 320 22‐day‐old Arbor Acres male broilers were randomly allotted into five groups with eight replicates of eight birds each. Broilers in the control group were housed at 22 ± 1°C and fed the basal diet. Broilers in the HS, HS‐EA_0.75, HS‐EA_1.00 and HS‐EA_1.25 groups were reared under HS (34 ± 1°C for 8 h/day and 22 ± 1°C for 16 h/day), and fed basal diet with 0, 0.75, 1.00 and 1.25 g/kg EA, respectively. The experiment ended at 42 days. Dietary 1.00 and 1.25 g/kg EA decreased blood pH and elevated body weight gain, feed intake and carcass yield compared to the HS group. Broilers fed EA diets had lower serum concentrations of malondialdehyde and corticosterone and activities of alanine aminotransferase and aspartate aminotransferase, and higher serum total superoxide dismutase activity, tri‐iodothyronine concentration and tri‐iodothyronine/thyroxine than the HS group. Serum catalase activity in HS‐EA_1.00 and HS‐EA_1.25 groups and activity to inhibit hydroxyl in the HS‐EA_1.00 group were higher than the HS group. In conclusion, dietary 0.75–1.25 g/kg EA addition alleviated HS induced impairments in broilers.