Sorghum silage supplemented with crambe meal improves dry matter intake and milk production in crossbred Holstein cows

We studied the feed intake and milk production of Holstein × Zebu crossbred cows fed sorghum silage diets and concentrates, with and without the addition of crambe meal. Using a change-over design for a total of 120 days, eight cows were fed two diets (concentrates + silages with and without crambe meal) in four 30-day periods, with four replications (animals). The crambe meal diet increased (P < 0.05) the dry matter intake (DMI), crude protein intake (CPI), and non-fibrous carbohydrates intake (NFCI) as well as milk production (4.3%). No difference was noted (P > 0.05) for the milk composition between the treatments. Crambe meal as an additive in sorghum silage (100 g/kg in natural matter) showed a great potential for introduction in dairy farming as it substantially increases CP intake, does not reduce food intake, raises animal productivity, and does not affect milk composition.     

Performance of Arsi-Bale sheep fed urea treated maize cob as basal diet and supplemented with graded levels of concentrate mixture

The experiment was conducted using 20 yearling intact male Arsi-Bale sheep with a mean body weight of 20.56?±?0.45 (mean?±?SD) to investigate the performance and economic benefit of graded levels of concentrate supplementation to urea-treated maize cob (UTMC)-based diet. The experiment consisted of 7 days of digestibility trial and subsequent 90 days of feeding trial. Before the commencement of the experiment, sheep were vaccinated against common infectious diseases, dewormed, and disinfected against internal and external parasites, respectively. The experimental design was randomized complete block design. The sheep were grouped into five blocks of four animals based on their initial body weight, and one animal from each block was randomly assigned to one of the four treatments. The treatments included ad libitum feeding of UTMC (T1) and supplementation with a concentrate mixture composed of wheat bran (WB) and noug seed cake (NSC) in 2:1 ratio, which were offered at 150 g (T2), 250 g (T3), and 350 g (T4) DM/head/day. The CP content of the UTMC was 9.3% on DM basis. The daily DM intake of UTMC was higher (P?<?0.001) for T4 (614.6 g) compared to T1 (505.1 g), T2 (538.9 g), and T3 (590.3 g). Total DM intake was higher (P?<?0.001) for supplemented treatments T2 (688.4 g), T3 (844.1 g), and T4 (966.9 g). Supplementation did not improve (P?>?0.05) digestibility of DM, OM, NDF, and ADF, except CP digestibility which was significant (P?<?0.001) across treatments. Supplementation increased (P?<?0.001) final body weight (FBWT), feed conversion efficiency (FCE), and average daily weight gain (ADG). The average daily gain (ADG) was highest (P?<?0.001) in T4 (80.8?±?7.74 g/day) followed by T3 (33.3?±?7.74 g/day) and T2 (23.1?±?0.95 kg) whereas the un-supplemented animals lost about 9.2 g/day. The highest total return, net income, and marginal rate of return were observed in higher level supplemented sheep than the control. Therefore, T4 improved biological performance and marginal rate of return than the other treatments and can be considered as better alternative feed supplement in UTMC-based feeding of Arsi-Bale sheep in Ethiopia.     

Growth performance,economic benefits and sensory characteristics of meat from broilers finished on <Emphasis Type="Italic">Acacia anguistissima</Emphasis> leaf meal-based diets

The objective of the study was to determine growth performance, viscera organ development, economic benefit and sensory characteristics of meat from broilers finished on Acacia anguistissima leaf meal-based diets. One hundred and eighty Cobb 500-day-old chicks were used in the study. Acacia anguistissima was used as a protein source and included in broiler diets at 0, 50 and 100 g/kg. Total feed intake (TFI), average daily gain (ADG), and gain to feed ratio (G:F) and cost benefit analysis were determined. There were no differences in TFI of broilers across treatments diets. Average daily gain and gain to feed (G:F) ratio were low (P?<?0.05) for broilers feeding on diet with100 g/kg acacia meal. Highest returns from weight gain were obtained from broiler chickens fed on diet with 50 g/kg inclusion level of A. anguistissima (P?<?0.05). Intestinal length increased with inclusion level of A. anguistissima whereas liver and spleen weight decreased with inclusion level of A. anguistissima (P?<?0.05). Female consumers gave higher scores for overall flavour intensity than male consumers (P?<?0.05). Treatment diets influenced consumer sensory characteristics of broiler meat (P?<?0.05). High sensory scores were observed for overall flavour intensity (OFI) for both boiled and deep fried meat from broilers fed 100 g/kg A. anguistissima. It can be concluded that A. anguistissima meal can be used effectively up to 50 g/kg in broiler diets without compromising performance of chickens and can influence a few sensory characteristics.     

Effects of different dietary inclusion levels of macadamia oil cake on growth performance and carcass characteristics in South African mutton merino lambs

Growth performance and carcass characteristics of South African mutton merino fed graded levels of macadamia oil cake were assessed. A total of 60 South African mutton merino lambs were used in the experiment (initial live weight 25.0?±?0.45 kg). Five diets with different inclusion levels of macadamia oil cake (MOC) were formulated: T1 (0% MOC, control), T2 (5% MOC), T3 (10% MOC), T4 (15% MOC) and T5 (20% MOC). Effects of inclusion level of MOC on average daily gain (ADG) and average daily feed intake (ADFI) were not significant (P?>?0.05). Effects of inclusion levels of MOC on feed conversion ratio (FCR) of sheep were significant (P?<?0.05). Highest proportion (71.2%) of sheep in the study had a carcass fat classification of 2, followed by a proportion of 17.3% sheep with a carcass fat classification of 3 and lastly 11.5% sheep had carcass fat classification of 4. Warm and cold carcass mass, chest circumference, carcass length and dressing percentage were higher in sheep fed on 5% MOC compared to other treatment diets (0, 10, 15 and 20% MOC) (P?<?0.05). Fat rib eye had a greater area in sheep fed on 5% MOC (P?<?0.05). It was concluded that 5% MOC provided the best results in terms of carcass characteristic measurements in sheep.     

Effects of substituting sow and weaner meal with brewers’ spent grains on the performance of growing pigs in Rwanda

Nutrient composition of brewers’ spent grains (BSG) from two industries and sow and weaner meal (SWM) were different (p < 0.05). In completely randomised design (CRD), thirty (30) Landrace x Pietrain crosses 35 to 40 ± 5 kg were randomly allocated to 10 pens each with 3 pigs based on the initial weight. Five diets were assigned to pig, where BSG replaced SWM at 0% (T1), 25% (T2), 50% (T3), 75% (T4) and 100% (T5) on DM basis. Daily feed intake and weekly live weight, feed conversion ratio (FCR) and the net profit were recorded for 42 days. Feed intake increased from T1-T3 and then decreased (p < 0.05). The average daily gains (ADG) were different (p < 0.05), but T1 to T3 were similar (p > 0.05). FCR was similar (p > 0.05) from T1 to T3 but different for T4 and T5 (p < 0.05). Feed cost decreased with the increase in BSG levels. The net return was highest in T3 (50% BSG) than in T1 and T2 but lower in T5. It was concluded that BSG can replace 50% SWM in grower pigs’ diets without adverse effect on daily gain with good economic returns.     

Evaluation of rumen-protected choline additive to diet on productive performance of male Zaraibi growing goats during hot summer season in Egypt

Twenty Zaraibi goat bucks were used in this experiment which lasted 3 months during summer season of Egypt. The animals were divided randomly into two equal groups. The first group was kept without treatment as control while in the second group, rumen-protected choline (RPC) at the level of 20 g/buck/day was added to the concentrate feed mixture at the morning feeding. RPC additives to diet of Zaraibi goat bucks during the period of hot summer season increased (P < 0.01) total gain and average daily gain compared to the control group. RPC increased (P < 0.05) dry matter intake and feed conversion while water intake was not affected by RPC additives. RPC increased (P < 0.05) red and white blood cell (RBC × 10⁶, WBC × 10³) counts and hemoglobin concentration and hematocrit percentage. RPC increased total protein (P < 0.05), globulin, and γ-globulin (P < 0.01). On the other hand, total lipids, total cholesterol, and triglyceride concentrations decreased (P < 0.05 and P < 0.05) while phospholipids, glucose, and choline concentrations increased (P < 0.01) due to RPC supplementation. RPC increased (P < 0.01) thyroxin and triiodothyronine, increased (P < 0.05) testosterone levels, and decreased (P < 0.01) cortisol level compared with control bucks. It is concluded that dietary RPC at the rate of 20 g daily is required for growing male goats, especially, under heat stress conditions of summer season in Egypt and showed the best results concerning the growth, feed conversion, blood metabolites, and economic efficiency.     

Body weight change of Abergelle breed and Abergelle crossbred goats fed hay supplemented with different level of concentrate mixture

The experiment was conducted at Sekota District using 36 intact yearling males of pure Abergelle breed and Abergelle crossbred goats (50%) with a mean live weight of 18.92?±?0.72 kg (mean?±?SE). The objective of the experiment was to evaluate the effect of different levels of concentrate mixture supplementation on feed intake, live weight gain, and economic gain of the breeds. Goats were blocked based on initial body weight and were randomly assigned to the dietary treatments. The experimental design was a 2?×?3 factorial in RCBD (randomized complete block design). The treatments included ad libitum feeding of local grass hay and supplementation with three levels (184, 368, and 552 g/day) of concentrate mixture. The experiment consisted of 90 days of feeding. Daily, total dry matter and CP (crude protein) intakes were affected by diet and genotype (P?<?0.01). Significant decrease (P?<?0.001) in hay intake was observed as the level of the supplement increased. Besides, substitution rate increased with increasing levels of supplementation. Average daily body weight gains were significantly impacted only by diet. Animals fed on 184 significantly lower weights, while nonsignificant difference was observed in live weight gain between 368 and 552 supplemented group. Supplementation of 368 concentrate mix significantly improved (P?<?0.05) feed intake, daily weight gain, and feed conversion efficiency. Supplementation of 368 g/day had showed significantly higher net return for both goat breeds. However, the Abergelle breed was significantly better in net profit and sensitivity than the crossbreed. Both genotypes performed better with the diet containing 368 g/day than that with 184 and 552 g/day of concentrate supplementation.     

Performance,endocrine, metabolic,and reproductive responses of Nellore heifers submitted to different supplementation levels pre- and post-weaning

The present study was conducted to evaluate the effects of high and low supplementation levels pre- and post-weaning on performance, endocrine, metabolic, and reproductive responses of Nellore heifers. Fifty Nellore heifers with 132?±?9.9 kg average body weight (BW) and 138?±?19 days of age were supplemented from 4 to 14 months. The heifers were distributed into five supplementation plans: HH—6 g/kg of BW of supplement pre- and post-weaning, HL—6 g/kg of BW of supplement pre-weaning and 3 g/kg post-weaning, LH—3 g/kg of BW pre-weaning and 6 g/kg of BW post-weaning, LL—3 g/kg of BW pre- and post-weaning, and CC—control, no supplementation. Interactions were not significant (P?>?0.10). The level of supplement fed pre-weaning did not affect any of the performance variables evaluated at the end of the experiment (P?>?0.10). There was a significant effect of supplementation and level of supplementation fed post-weaning on average daily gain (ADG) and final BW (P?<?0.05). Overall ADG was also affected only by supplementation and level of supplement fed post-weaning (P?<?0.05) with animals receiving 6 g/kg of BW post-weaning gaining more weight. Follicular diameter was greater in animals that received 6 g/kg of BW post-weaning (P?<?0.05). In summary, performance, endocrine, metabolic, and reproductive variables evaluated in the current study were improved by the level of supplement fed post-weaning. Heifers receiving supplementation of 6 g/kg of BW post-weaning had greater responses, independent of the level received during the pre-weaning phase.     

Effects of supplements containing different additives on nutritional and productive performance of beef cattle grazing tropical grass

A grazing trial was carried out to evaluate the inclusion of three feed additives in supplements (crude protein, CP 230 g/kg dry matter, DM) on the performance, voluntary intake, and digestibility of beef heifers grazing Brachiaria decumbens (CP 81 and neutral detergent fiber, NDF 615 g/kg DM). Thirty-five Nellore heifers (21 months of age and 383 ± 6.29 kg of body weight, BW) were used in a completely randomized design. The treatments were as follows: no supplement (control); supplement fed at 1 kg/animal/day without additives (S); supplement with monensin (S + M); supplement with yeast culture (S + YC); and supplement with enzyme complex (S + EC). All of the supplemented heifers had greater (P < 0.1) average daily gain (～0.186 kg/day) compared to the control treatment (0.014 kg/day). Average daily gain and final BW were similar (P > 0.1) among supplemented heifers. Monensin inclusion in the supplement decreased (P < 0.1) forage DM (expressed as g/kg BW) and NDF intake (expressed as kg/day and as g/kg BW). All of the feed additive inclusions decreased (P < 0.1) NDF digestibility. In conclusion, the heifers’ performance was improved by concentrate supplementation. However, the inclusion of additives did not enhance this effect.     

Effects of quebracho tannin extract on intake,digestibility, rumen fermentation,and methane production in crossbred heifers fed low-quality tropical grass

The aim of this work was to evaluate the effect of quebracho tannins extract (QTE) on feed intake, dry matter (DM) digestibility, and methane (CH₄) emissions in cattle fed low-quality Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 295 ± 19 kg were allotted to five treatments (0, 1, 2, 3, and 4% QTE/kg DM) in a 5 × 5 Latin square design. Intake, digestibility, and total methane emissions (L/day) were recorded for periods of 23 h when cattle were housed in open-circuit respiration chambers. Dry matter intake (DMI), organic matter intake (OMI), dry matter digestibility (DMD), and organic matter digestibility (OMD) were different between treatments with 0 and 4% of QTE/kg DM (P < 0.05). Total volatile fatty acid and the molar proportion of acetate in the rumen was not affected (P < 0.05); however, the molar proportion of propionate increased linearly (P < 0.01) for treatments with 3 and 4% QTE. Total CH₄ production decreased linearly (P < 0.01) as QTE increased in the diet, particularly with 3 and 4% concentration. When expressed as DMI and OMI by CH₄, production (L/kg) was different between treatments with 0 vs 3 and 4% QTE (P < 0.05). It is concluded that the addition of QTE at 2 or 3% of dry matter ration can decrease methane production up to 29 and 41%, respectively, without significantly compromising feed intake and nutrients digestibility.     

Performance and carcass characteristics of lambs fed diets with increasing levels of <Emphasis Type="Italic">Mimosa tenuiflora</Emphasis> (Willd.) hay replacing Buffel grass hay

This study evaluated the performance and carcass characteristics of lambs fed diets with increasing levels of Mimosa tenuiflora (Willd.) hay replacing Buffel grass (Cenchrus ciliaris). Twenty-eight Santa Inês male lambs with an average body weight (BW) of 20.3 ± 1.49 kg(mean ± SD) were allocated in individual stalls and distributed in a completely random design with four treatments (0, 20, 40, and 60 g/100 g total DM M. tenuiflora hay replacing Buffel grass hay in diet) with seven replications. M. tenuiflora hay at the level of 20% dry matter (DM) total replacing Buffel grass hay increased final weight (P = 0.006), total weight gain (P < 0.001), average daily weight gain (ADWG; P < 0.001), DM intake (P < 0.001), and feed efficiency (P < 0.001). Intake of crude protein, NDF_ap, ADF_ap, ash, ether extract, total and non-fibrous carbohydrates, and total digestible nutrients presented a positive quadratic effect with M. tenuiflora hay replacing Buffel grass hay and 40 g/100 g total DM level presented greater intake. There were positive quadratic effects by M. tenuiflora hay inclusion at 20 g/100 g total DM level on slaughtering weight (P = 0.005), hot carcass weight (P = 0.002), cold carcass weight (P = 0.002), empty body weight (P = 0.001), hot carcass yield (P = 0.002), cold carcass yield (P = 0.003), and increase linear on biological yield (P = 0.003). There was no influence on cooling weight loss (P = 0.284). M. tenuiflora hay may be included in lamb diets at amounts up to 20 g/100 g total DM substitution of Buffel grass hay because increase in the nutrients intake, growth performance, and carcass characteristics.     

低蛋白质氨基酸平衡饲粮对早期断奶仔猪腹泻和生产性能的影响

本研究选用１８头２８±１日龄断奶的杂交仔猪（平均体重约５．５ｋｇ），研究低蛋白质氨基酸平衡饲粮对早期断奶仔猪腹泻和生产性能的影响。试验结果显示：（１）低蛋白质氨基酸平衡饲粮使仔猪血浆挥发性盐基氨含量、血浆尿素氨含量和腹泻指数降低（Ｐ＜０．０５或０．０１）。（２）采食全植物蛋白型氨基酸平衡饲粮（ＣＰ１８．３％）的仔猪，其平均日增重（ＡＤＧ）、平均日采食量（ＡＤＦＩ）和料肉比（Ｐ／Ｇ）与采食复合蛋白型对照饲粮（ＣＰ１９．７％）的仔猪差异不显著（Ｐ＞０．０５），但前者的增重成本比后者降低（Ｐ＜０．０５）３１％。（３）采食复合蛋白型氨基酸平衡饲粮（ＣＰ１８．４％）的仔猪的生产性能优于采食复合蛋白型对照饲粮（ＣＰ１９．７％）的仔猪，前者的ＡＤＧ和ＡＤＦＩ分别提高（Ｐ＜０．０５）６１％和３２％，Ｆ／Ｇ和增重成本分别下降（Ｐ＜０．０５）２４％和３７％。（４）采食全植物蛋白型氨基酸平衡饲粮的仔猪，其ＡＤＧ和ＡＤＦＩ低于（Ｐ＜０．０１）采食复合蛋白型氨基酸平衡饲粮的仔猪。前者的Ｆ／Ｇ和增重成本趋于高于后者，但差异不显著（Ｐ＞０．０５）。以上结果表明，低蛋白质氨基酸平衡饲粮可显著降低仔猪断奶后腹泻和提高仔猪生产性能。复合蛋白型?     

苦玄参提取物对仔猪生长性能的影响研究

[目的]试验旨在探讨苦玄参提取物对仔猪生长性能的影响,为其在动物生产中更好地应用提供参考依据。[方法]选取体重相近的28~35日龄杜×长×大三元杂交的健康断奶仔猪250头,随机分为5组(A、B、C、D、E组),每组设5个重复,每个重复10头。其中,A、B、C组依次为苦玄参提取物高、中、低3个剂量试验组,分别在基础日粮中添加3.500、1.750和0.875g/kg苦玄参提取物;D组在基础日粮中添加对照药物七补散4.0g/kg;E组为空白对照组,饲喂基础日粮,预饲期7d,正试期30d。于试验正式开始的第0天、第15天和第30天7:00分别对各组的每一头试验猪进行空腹称重,并每天记录每个组试验猪的采食量,计算平均日采食量(ADFI)、平均日增重(ADG)和料重比(F/G)。[结果]添加苦玄参提取物后,A、B、C组仔猪的体重、ADG及ADFI,与E组相比显著或极显著(P<0.05或P<0.01)增加,而料重比降低;其中苦玄参提取物中剂量组仔猪的体重、平均日增重及平均日采食量提升最明显,料重比也极显著低于D组与E组(P<0.01)。[结论]苦玄参提取物对仔猪生长具有一定的促进作用,以1.750g/kg的添加剂量添加在饲料中效果最佳。     

Strategic supplementation of cassava top silage to enhance rumen fermentation and milk production in lactating dairy cows in the tropics

High-quality protein roughage is an important feed for productive ruminants. This study examined the effects of strategic feeding of lactating cows with cassava (Manihot esculenta) top silage (CTS) on rumen fermentation, feed intake, milk yield, and quality. Four early lactating crossbred dairy cows (75% Holstein-Friesian and 25% Thai) with body weight (BW) 410?±?30 kg and milk yield 12?±?2 kg/day were randomly allotted in a 4?×?4 Latin square design to four different supplementation levels of CTS namely, 0, 0.75, 1.50, and 2.25 kg/day of dry matter (DM). Strategic supplementation of CTS significantly affected ruminal fermentation end-products, especially increased propionate production, decreased protozoal population and suppressed methane production (P?<?0.05). Increasing the CTS supplementation level substantially enhanced milk yield and the 3.5% FCM from 12.7 to 14.0 kg/day and from 14.6 to 17.2 kg/day (P?<?0.05) for non-supplemented group and for the 2.25 kg/day supplemented group, respectively. We conclude that high-quality protein roughage significantly enhances rumen fermentation end-products, milk yield, and quality in dairy cows.     

Comparison of silage and hay of dwarf Napier grass (<Emphasis Type="Italic">Pennisetum purpureum</Emphasis>) fed to Thai native beef bulls

Both quantity and quality of forages are important in dry season feeding. Eight Thai native beef bulls were arranged in a Completely randomized design to evaluate dwarf Napier namely Sweet grass (Pennisetum purpureum cv. Mahasarakham) preserved as silage or hay on feed intake, digestibility, and rumen fermentation. The animals were fed with forage ad libitum supplemented with concentrate mixture at 1.0% of BW for 21 days; data were collected during the last 7 days. The results showed that there were differences (P?<?0.05) between treatments in dry matter (DM) intake, DM digestibility, and ruminal pH, in which hay feeding gave enhanced feed intake and more favorable ruminal pH. Nevertheless, mean ruminal ammonia nitrogen, total volatile fatty acids (TVFAs), proportion of VFAs, bacterial and protozoal population, and blood urea nitrogen were similar (P?>?0.05) in animals fed silage and hay. Sweet grass is better preserved as hay rather than silage.     

Partial or total replacement of commercial concentrate with on-farm-grown mulberry forage: effects on lamb growth and feeding costs

Replacing commercial concentrate with mulberry foliage was evaluated in a feeding trial lasting 126 days. Forty-eight weaned male Pelibuey lambs (20.6?±?0.80 kg of BW) were randomly allocated to four groups: (1) supplementing the basal diet with mulberry at 1% (DM basis; M-1), (2) mulberry at 0.75% plus 0.1 kg concentrate fresh matter basis (M-0.75), (3) mulberry at 0.50% plus 0.2 kg concentrate (M-0.50) and (4) basal diet plus 0.3 kg concentrate (control; M-0). During the first 90 days, the basal diet was Pennisetum purpureum forage which was substituted by a mixture of guinea grass and sugarcane from 90 days. Average daily gain (ADG, g/day), dry matter intake (DMI) and feed conversion rate (FCR; DMI/ADG) were determined. The ADG was affected (P?<?0.01) by the diet, with the lowest obtained in M-1 lambs (71?±?6.4 g/day), whereas no differences among the other groups were observed (94?±?6.4 g DM/lamb). The DMI was higher (P?<?0.01) in M-0 (937 g DM/lamb) which concomitantly affected differences in FCR (11.9, 9.9, 10.5 and 9.7 kg DMI/kg BW gain for M-1, M-0.75, M-0.50 and M-0 lambs, respectively). Final BW at slaughtering and hot or cold carcass yields were coherent with growth rate findings. Biological yield (cold carcass weight/empty BW) was higher (P?<?0.01) in M-0.75. Without compromising animal productivity, replacing imported concentrate with mulberry reduced the feeding cost. Optimum results were obtained with M-75 diet. Further studies must be conducted for optimizing energy/protein ratios with different ingredients while increasing DMI and lamb growth rates in this tropical genotype.     

Impact of black soldier fly larval meal on growth performance,apparent digestibility,haematological and blood chemistry indices of guinea fowl starter keets under tropical conditions

In order to assess the impact of larval meal on guinea fowl, six iso-caloric and iso-nitrogenous diets were fed to day-old-keets ad libitum till 8 weeks of age. Water was also freely provided. The fishmeal (FM) component of the experimental diets was replaced with black soldier fly larval meal (BSFLM) in the following percentage ratios of 0–100%. Results showed that body weight gain significantly (P < 0.05) increased in all the BSFLM treatment groups compared to the control group. The final body weight of the birds at age 8 weeks differed significantly (P < 0.001). Dry matter intake varied (P < 0.001) slightly among the birds but never affected (P > 0.05) ME intake and faecal output as well as weight changes of the keets. Digestibility of dry matter and energy were not affected (P > 0.05) by the differences in diet. Organ and haematopoietic integrity were assured regardless of the protein types used as well as levels of inclusion. The results suggest that the replacement of fishmeal with BSFLM in so far as the economics of production is concerned could result in reduced feed cost for starter guinea keet judging from diets that contained 60–100% BSFLM.     

小麦全株青贮饲料饲喂育肥猪效果研究

为探讨小麦全株青贮饲料的饲喂方法,以汶鑫黑猪和三元(杜×长×大)杂交猪为研究对象,通过饲养对比试验,证明小麦全株青贮饲料在中国地方猪和进口三元猪上应用的可行性.选择体重相近的汶鑫黑猪120头,分别饲喂基础日粮和用14％的小麦全株青贮饲料替代基础日粮,测定平均日采食量和平均日增重;同时,选取体重相近(60±0.16 kg...     

Correlation between production performance and feeding behavior of steers on pasture during the rainy-dry transition period

The aim of this study was to evaluate the correlation between production performance and feeding behavior of steers reared on pasture during the rainy-dry transition period. Twenty-two ½ Holstein-Zebu crossbred steers at an average age of 10 months and with an average initial body weight of 234.5 ± 16.0 kg were distributed in a completely randomized design with two types of supplementation and eleven replications. Pearson’s linear correlation analysis was performed between behavioral variables and weight gain and feed conversion. Correlation coefficients were tested by the t test. The time expended feeding at the trough was positively correlated (P < 0.05) with average daily gain (ADG) and with the number of periods of permanence at the trough. Bite rate and the number of bites per day were positively correlated (P < 0.05) with ADG and negatively (P < 0.05) with feed conversion, unlike the number of bites per swallow, which was negatively correlated (P < 0.05) with ADG. There was a positive correlation (P < 0.05) between feed efficiency in dry matter and neutral detergent fiber and ADG. Feeding behavior characteristics have little association with the production performance of cattle on pasture receiving mineral or energy-protein supplementation.     

低聚木糖对生长肥育猪生长性能、胴体性状和肉品质的影响

为了研究低聚木糖(XOS)对生长肥育猪生长性能、胴体性状和肉品质的影响,试验选取平均体重为30 kg左右的三元杂交猪80头,随机分为8组,每组10头,公、母各占1/2,单栏饲养。试验设对照组、抗生素组,3065 kg阶段100、250和500 g/t XOS组,以及30100 kg阶段100、250和500 g/t XOS组。分别于试验开始和结束时记录每头猪的空腹体重及采食量,计算平均日采食量(ADFI)、平均日增重(ADG)和料重比(F/G);于试猪平均体重达100 kg时屠宰采样,测定胴体性状、肉品质和肌肉化学成分。结果表明:与对照组或抗生素组相比,饲粮添加不同剂量的XOS对生长肥育猪的ADFI、ADG、F/G、胴体性状和肉品质均无显著影响(P0.05);3065 kg阶段添加250 g/t XOS可显著增加脾脏指数以及背最长肌粗蛋白质含量(P0.05);30100 kg阶段添加500 g/t XOS可显著增加脾脏指数及背最长肌粗蛋白质含量(P0.05)。综上所述,饲粮添加不同剂量的XOS虽对生长肥育猪的ADFI、ADG、F/G、胴体性状和肉品质等指标影响不显著,但可通过增加肌肉粗蛋白质含量而改善猪肉营养价值;以30100 kg阶段添加500 g/t XOS效果较佳。