AA父母代种蛋孵化期间失重对孵化效果的影响

为了研究肉鸡种蛋孵化过程中失重对孵化效果的影响,试验采用同一鸡场同一天入库的种蛋,按蛋重区间分成10组,每组150枚,孵化时各组保留受精蛋100枚,测定失重率、孵化率、健雏率、初生雏重。结果表明:种蛋的失重总趋势为快—慢—快,初生雏重随着蛋重的增加而增加。     

籽鹅种蛋蛋重与蛋形指数对孵化效果影响的研究

本试验旨在研究不同水平蛋重与蛋形指数对籽鹅种蛋孵化效果的影响,进而总结出种蛋筛选的最佳方案,为籽鹅个体、家系种蛋的选留及籽鹅的繁衍、孵化、生产提供科学参考。选取二年籽鹅种蛋2 469枚,蛋重为94.8~154.4 g,平均蛋重（123.3±9.5）g;蛋形指数为1.24~1.63,平均蛋形指数1.45±0.05。采用2因素4水平试验设计,将所有种蛋按蛋重与蛋形指数分成16个孵化组（蛋重与蛋形指数分别分为4个水平）,测量每枚种蛋蛋重与蛋形指数,并在蛋壳上做好编号,在相同孵化条件、同一孵化设备中进行两次孵化试验。结果表明,①蛋重<118.0 g组种蛋受精率最高,>131.9 g组次之;>131.9 g组种蛋受精蛋孵化率最高,125.0~131.9 g组次之,且受精蛋孵化率随着蛋重增大升高;125.0~131.9 g组种蛋孵化健雏率最高,>131.9 g组次之;>131.9 g组种蛋孵出鹅雏出生重最大。②蛋形指数在1.47~1.51组种蛋受精率及种蛋孵化健雏率最高,>1.51组次之;1.47~1.51组种蛋受精蛋孵化率最高,1.42~1.46组次之。分析以上结果可得出：籽鹅种蛋蛋重对种蛋受精率、受精蛋孵化率、健雏率、鹅雏出生重有显著影响（P<0.05）,以籽鹅蛋重在125.0~154.4 g为宜;蛋形指数对种蛋受精率、受精蛋孵化率、健雏率亦有显著影响（P<0.05）,对种蛋孵出鹅雏出生重无影响（P>0.05）,以蛋形指数在1.47~1.51为宜。籽鹅种蛋蛋重与蛋形指数对受精率、受精蛋孵化率、健雏率、鹅雏出生重的影响均存在交互作用。其中,蛋形指数对种蛋孵化健雏率的影响较蛋重强,其作为单一因素对鹅雏出生重无影响。以上结果表明,以蛋重或蛋形指数任一因素作为种蛋筛选的依据都不科学,应综合考虑以达到种蛋优选的目的。     

不同饲养方式对柴鸡繁殖性能的影响

试验旨在研究不同饲养方式对柴鸡繁殖性能的影响.通过对孵化场来自放养华北柴鸡和笼养华北柴鸡不同季节种蛋孵化性能调查,并进行饲养试验比较两种来源种蛋后代饲养效果.结果表明:放养鸡种蛋受精率、孵化率和健雏率极显著低于笼养鸡种蛋(P<0.01),死胚率极显著高于笼养鸡种蛋;季节显著影响种蛋受精率(P<0.05)、受精蛋孵化率(P<0.05)、入孵蛋孵化率(P<0.05)和健雏率(P<0.01);季节和种蛋来源对受精蛋孵化率、健雏率存在互作效应(P<0.05).但是,放养条件好的情况下种蛋也可以达到种鸡场种蛋一致的孵化性能效果.不同来源种蛋对雏鸡的生长性能均没有显著差异(P>0.05).放养鸡种蛋影响孵化性能,但对雏鸡饲养效果没有影响,管理条件好的放养鸡可以留作种用.     

蛋重对汶上芦花鸡孵化效果的影响

本试验探索了不同蛋重对汶上芦花鸡种蛋孵化效果的影响。将挑选的324枚健康种蛋按蛋重分为3组:Ⅰ组(39.65～44.82 g),Ⅱ组(45.07～49.44 g),Ⅲ组(50.18～56.78 g),测算种蛋3个胚龄的失重和失重率,并对孵化效果和雏鸡初生重进行分析。结果显示:Ⅲ组的受精率、受精蛋孵化率、入孵蛋孵化率最高;种蛋的失重随蛋重增加而显著增大(P0.05),但失重率无显著差异(P0.05);雏鸡初生重随着蛋重的增加而显著增大(P0.05)。汶上芦花鸡蛋重区间为50.18～56.78 g时孵化效果最好。     

孵化场如何消毒

<正>孵化场卫生状况直接影响种蛋孵化率、健雏率及雏鸡的成活率。一个合格的受精蛋孵化为健康的雏鸡,在整个孵化过程中所有与之有关的设备、用具都必须     

朝鲜鹌鹑种蛋重和蛋形指数对孵化效果的影响

选取288枚朝鲜鹌鹑种蛋,按蛋重、蛋形指数大小各分为3组,在相同条件下孵化,研究蛋重和蛋形指数对孵化效果的影响。试验结果表明:蛋重、蛋形指数对受精蛋孵化率的影响均极显著(P<0.01)。蛋形指数对健雏率的影响显著(P<0.05),蛋重对健雏率的影响不显著(P>0.05)。     

不同地区边鸡种蛋孵化效果比较

为了比较不同地区边鸡种蛋的孵化效果,试验选择山西忻州市、山西右玉县、内蒙古通辽市、内蒙古凉城县、河北张家口市、内蒙古卓资县、内蒙古包头市7个地区(7个地区按照以上顺序分别设置为试验1,2,3,4,5,6,7组)的各8只210日龄边鸡所产的种蛋各100枚,采用机器孵化法孵化种蛋,测定和计算各组种蛋的受精率、受精蛋数、破损蛋数、破损率、出雏数、入孵蛋孵化率、受精蛋孵化率、5胚龄死胎蛋数、10胚龄死胎蛋数、19胚龄死胎蛋数、入孵蛋重、5胚龄失重、5胚龄失重率、19胚龄失重、19胚龄失重率、初生重、初生重占蛋重比例,分析比较各地区边鸡种蛋孵化效果。结果表明:试验4组受精蛋数最多,受精率、出雏数、入孵蛋孵化率、受精蛋孵化率最高,破损率最低,5胚龄死胎蛋数最少,19胚龄死胎蛋数最少;试验3组破损率最低,10胚龄死胎蛋数最少;试验7组19胚龄死胎蛋数最少。试验6组种蛋的入孵蛋重最重,与试验5组差异不显著(P>0.05),而显著高于试验1,2,3,4,7组(P<0.05);试验6组5胚龄失重、19胚龄失重率、初生重最高,与试验4,5组差异不显著(P>0.05),而显著高于试验1,2,...     

孵化器开启风门时间对孵化率的影响

孵化器开启风门时间对孵化质量的影响试验使用28周龄农大3号父母代种鸡的种蛋共33600枚,放入两台相同的孵化器中各16800枚进行孵化。一台5d正常开启风门,一台10d开启风门,中间测定孵化箱内的CO2浓度。测定延期开风门对受精率、死精率、受精蛋孵化率、入孵蛋孵化率、健雏率、死胎率的影响。试验结果表明,种蛋孵化过程中10d开启风门,受精蛋孵化率和入孵蛋孵化率提高,差异极显著(P<0.01),健雏率上升,差异显著(P<0.05),受精率和早期死胚率无明显差异。     

蛋重、蛋形和蛋色对北京油鸡种蛋孵化性能的影响

研究测定了44~48周龄北京油鸡的蛋重、蛋形指数和蛋壳颜色,并分析其对种蛋孵化性能的影响。结果显示,北京油鸡蛋重、蛋形指数和蛋色均较一致;蛋重对孵化性能影响不显著(P0.05),但是随着蛋重的增加孵化性能有增加的趋势;蛋形指数对受精蛋孵化率的影响显著(P0.05),蛋形指数0.75~0.80的种蛋组显著高于其他组;蛋壳颜色对北京油鸡的受精率、受精蛋孵化率和健雏率均无影响(P0.05)。本研究结果为北京油鸡的选种提供了重要的参考依据。     

鸡胚胎期及生长发育早期对孵化绿光强度的反应

试验旨在探究孵化期单色绿光不同光照强度对鸡孵化和早期生长发育的影响。选用810个大小均匀的新浦东鸡种蛋,随机分为3组（n=270）,孵化期1~18.5 d分别在黑暗、低照度（20~50 lux）和高照度（200~300 lux）的LED单色绿光（λ=525 nm）条件下孵化,每天光照24 h,各组种蛋于第18.5天转至同一台无光出雏器中,各组温度和湿度等其他孵化条件始终保持一致。检测各组受精蛋孵化率、死胚率、初生重、10周龄体重、初生雏鸡及3周龄公鸡的血清激素浓度（甲状腺素、降钙素、生长激素、褪黑激素和骨钙素等）和血液生理生化指标（碱性磷酸酶、胰岛素样生长因子和钙等含量）。结果表明：各组种蛋的死胚数和死胚率差异较小;孵化的20.5 d低照度组和高照度组的受精蛋孵化率分别为黑暗组的2.3倍和5.2倍;孵化的21.5 d黑暗组的受精蛋孵化率为82.8%,低照度组和高照度组的孵化率分别比黑暗组高6.5%和1.9%;黑暗组的健雏率为98.6%,低照度组的健雏率比黑暗组低0.4%,而高照度组与黑暗组的健雏率接近;高照度组公雏初生重显著低于黑暗组（P<0.05）,而低照度组与黑暗组无显著差异（P>0.05）。母雏初生重趋势与公雏基本一致,高照度组母雏初生重显著低于其他两组（P<0.05）,其他两组之间无显著差异（P>0.05）;在10周龄,各组公鸡和母鸡体重无显著差异（P<0.05）;各组1日龄公雏血液生理生化和激素指标无显著差异（P>0.05）,3周龄公鸡高照度组和低照度组褪黑激素含量显著高于黑暗组（P<0.05）,其他指标无显著差异（P>0.05）。综上,在种蛋的孵化过程中,与黑暗条件下相比,给予适宜强度的单色绿光能够促进鸡胚发育,在不影响雏鸡健康的前提下使出雏时间提前,孵化期光照对后期生长发育影响较小。     

Plasma pharmacokinetics and milk levels of ceftriaxone following single intravenous administration in healthy and endometritic cows

Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition followed three-compartment open model. The values of Vd_area, AUC, t_1/2β, Cl_B, MRT and P/C ratio were 0.50 ± 0.19 L.kg⁻¹, 62.2 ± 23.3 μg.ml⁻¹.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg⁻¹.h⁻¹, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg⁻¹, 37.0 ± 17.1 μg.ml⁻¹.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg⁻¹.h⁻¹, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration. For MIC₉₀ of 0.5 μg.ml⁻¹ the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg⁻¹ repeated at 6 h intervals for the treatment of endometritis in cows.     

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (G_NPSP: Group of non-pregnant does with second sponge: n = 8; G_NPNSP: Group of non-pregnant does without second sponge: n = 6; G_PSP: Group of pregnant does with second sponge: n = 5; G_PNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (G_NPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. G_NPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or G_PSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. G_PNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle.     

Ovarian activity in F1 prepubertal ewe lambs under tropical conditions

Seventy crossbred ewe lambs, born from Pelibuey (PB) dams mated with five sire breeds: White Dorper × PB (WD × PB), Black Head Dorper × PB (BHD × PB), Ile de France × PB (Ile × PB) Katahdin × PB (KT × PB) and Pelibuey (PB × PB), were used to determine age and weight to puberty, follicular populations during prepubertal development, ovulation rate at first ovulation and function of the first corpus luteum (FCL). Ewe lambs were maintained under grazing conditions and were supplemented with 300 g head^− 1 day^− 1 of a concentrate with 14% CP and 3.0 Mcal ME kg^− 1 of DM. From 145 days of age, monthly observations were performed by endoscopy to monitor follicular populations and luteal structures. Ovarian follicles were classified according to size into small (≥ 1 and < 3 mm), medium (≥ 3 and ≤ 4 mm) and large (> 4 mm). Additionally, weekly observations by ultrasonography were performed in four ewes per genotype to assess follicular populations. Luteal function from first ovulation was determined by circulating concentrations of progesterone. Ovulation rate was not affected by genotype (P > 0.05). All breed groups had the same pattern of follicular populations, where most of follicles were small, followed by medium and a small proportion of large follicles. Maximum diameter of follicles was similar for all genotypes during prepubertal development (P > 0.05), with an average range of 3.9 ± 0.20 to 4.4 ± 0.20 mm. The BHD × PB reached puberty at the youngest age of 240.9 ± 13.0 days, compared to all other genotypes (P < 0.05), 259.1 ± 11.7 for WD × PB, 279.3 ± 9.6 for KT × PB and 289.0 ± 15.3 days for PB × PB and 308.6 ± 11.9 days for Ile × PB ewe lambs. Ile × PB had greater weight to first ovulation (31.5 ± 1.19 kg) as compared to other breed groups (P < 0.01). The largest percentage of FCL was for KT × PB ewes (100%) (P < 0.05), followed by BHD × PB (88.9%), PB × PB (83.3), WD × PB (78.6%) and Ile × PB (77.8%). There were no differences in ovulation rate attributable to type of lambing from which ewe lambs came from (P > 0.05). BHD × PB ewe lambs reached puberty at an earlier age than other in this study. KT × PB ewe lambs had the highest percentage of FCL in their first ovulation. Breed of sire Ile de France increased weight to puberty and decreased FCL at first ovulation. In conclusion, the BHD × PB ewe showed puberty at an earlier age than other genotypes, while the KT × PB had the highest percentage of functional corpus luteum in their first ovulation. Ewe lambs coming from single lambings reach puberty at a heavier weight than those coming from multiple lambings. The ovulation rate in the first ovulation of ewe lambs is not affected by genotype and type of lambing.     

Influence of dietary lysine level on whole-body protein turnover, plasma IGF-I, GH and insulin concentration in growing pigs

Four growing pigs (initial liveweight 25.9 ± 0.54 kg, final liveweight 43.0 ± 1.06 kg) were used to study the effect of dietary lysine level on nutrient digestibility, whole-body protein turnover, plasma insulin-like growth factor-I (IGF-I), growth hormone (GH), insulin, glucose, and urea nitrogen (PUN). Four diets, containing 7.0 g (L1), 9.5 g (L2), 12.0 g (L3) and 14.5 g (L4) lysine per kg diet respectively, were formulated as experimental treatments. The animals and diets were allocated in a 4 × 4 Latin square design. Nitrogen (N) metabolism and whole-body protein turnover were measured by classical method and single-dose ¹⁵N end-product method, respectively. The blood samples were taken at the end of each experimental period. Results showed that N retention (NR) and N biological value (NBV) were significantly increased from L1 to L4 (P < 0.05). However, differences in NR and NBV between L2, L3 and L4 were not significant (P > 0.05). There was no significant difference on dry matter (DM) digestibility, organic matter (OM) digestibility and N digestibility between different treatments (P > 0.05). Whole-body protein synthesis, protein degradation and protein accretion increased markedly from L1 to L2 (P < 0.05), but did not increase further from L2 to L4. Whole-body protein accretion (y, g/kg W^0.75/d) increased with dietary lysine (x, g/kg) in a quadratic manner: y = − 0.09x² + 2.12x − 5.14 (r² = 0.96, n = 4, P < 0.05).The results also showed that differences in plasma IGF-I, GH, glucose and PUN concentration between different treatments were not significant (P > 0.05). Plasma insulin concentration (y, μIU/ml) was increased with dietary lysine (x, g/kg) in a quadratic manner: y = 0.23x² − 4.10x + 32.25 (r² = 0.99, n = 4, P < 0.05), but it was not found that plasma insulin concentration was related to NR. A significant correlation was found between NR (y, g/d) and plasma IGF-I (x, ng/ml): y = − 3.1 × 10^− 3x² + 1.31x − 122.28 (r² = 0.99, n = 4, P < 0.05).It was concluded that dietary lysine level had a significant influence on NR and whole-body protein turnover but not on plasma IGF-I and GH concentration. Plasma IGF-I may be an important factor controlling N metabolism of growing pigs. Further research was needed to study the mechanism.     

Pharmacokinetics,plasma protein binding and bioavailability of moxifloxacin in Muscovy ducks after different routes of administration

In this study the disposition kinetics and plasma availability of moxifloxacin in Muscovy ducks after single intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administrations of 5 mg kg^?1 b.wt. were investigated. The concentrations of moxifloxacin in the plasma were measured using high-performance liquid chromatography (HPLC) with fluorescence detection on samples collected at frequent intervals after drug administration. Following intravenous injection, the decline in plasma drug concentration was bi-exponential with half-lives of (t_1/2α) 0.22 ± 0.10 h and (t_1/2β) 2.49 ± 0.26 h for distribution and elimination phases, respectively. The volume of distribution at steady-state (V_dss) was 1.02 ± 0.14 l kg^?1 and the total body clearance (Cl_tot) was 0.32 ± 0.11 l kg^?1 h^?1, respectively. After intramuscular and oral administration of moxifloxacin at the same dose the peak plasma concentrations (C_max) were 2.38 ± 0.43 and 2.11 ± 0.36 μg ml^?1 and were obtained at 1.47 ± 0.26 and 1.83 ± 0.16 h (T_max), respectively, the elimination half-lives (T_1/2el) were 3.14 ± 0.42 and 2.63 ± 0.44 h, respectively, and AUC_0–24 were 15.87 ± 2.35 and 14.52 ± 2.37 μg ml^?1 h^?1, respectively. The systemic bioavailabilities were 96.36 ± 11.54% and 86.79 ± 12.64%, respectively. In vitro plasma protein binding percent was 32%. We concluded that moxifloxacin might be clinically interesting alternative for the treatment of most sensitive bacterial infections in Muscovy ducks.     

Leptospirosis in Colombia: Isolation ofLeptospira SPP. from the kidneys of brown rats (Rattus Norvegicus) trapped on infected piggeries

Summary Leptospira interrogansserotypes pomonaand icterohaemorrhagiaewere isolated from the kidneys of Rattus norvegicustrapped on pomonainfected piggeries.The isolation of pomonafrom one of 111cultured kidneys, although of interest, strongly suggests that this rat does not play an important part in the epidemiology of infection by this serotype. Kidney tubular degeneration, focal mononuclear infiltrations and fibroplasia are morphological traces which remain after an attack of leptospirosis. The high percentage (48.6)of these lesions found in the rat kidneys examined does not seem to be related to serotype pomonabut to icterohaemorrhagiae.The importance of this last serotype in swine in the Cauca Valley has yet to be assessed.

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Leptospirosis En Colombia: Aislamiento DeLeptospira SPP. De Riñones De Ratas Pardas (Rattus Norvegicus) Atrapadas En Porquerizas Infectadas

Resumen Se aislóLeptospira interrogans serotipospomona eicterohaemorrhagiae de riñones deRattus norvegicus atrapadas en porquerizas infectadas porpomona. El aislamiento depomona de 1/111 riñones cultivados, aunque de interés, sugiere que esta rata no desempeña parte importante en la epidemiología de las infecciones por este serotipo.Degeneración tubular renal, infiltración mononuclear focal y fibroplasia son huellas morfológicas que quedan después de un ataque de leptospirosis. El alto porcentaje (48.6) de estas lesiones encontradas en los riñones de las ratas examinadas no parece estar relacionado con el serotipopomona sino con elicterohaemorrhagiae. La importancia de este último seroptipo en cerdos en el Valle del Cauca no se ha evaluado todavía.

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Leptospiroses En Colombie: Isolement DeLeptospira SPP. De Reins De Rats Bruns (Rattus Norvegicus) Captures Dans Des Porcheries

Résumé Les sérotypespomona eticterohaemorrhagiae deLeptospira interrogans ont été isolés de reins deRattus norvegicus capturés dans des porcheries infectées de (pomona?). L'isolement depomona sur une seule des 111 cultures de rein effectuées, bien qu'interessant, suggère fortement que ce rat ne joue pas un rôle important dans l'épidémiologie de l'infection par ce sérotype.La dégénerescence tubulaire des reins, des infiltrations ponctuelles par des monocucléaires et l'aspect fibreux constituent les traces morphologiques qui demeurent après une attaque de leptospirose. Le pourcentage élevé (48,6) de ces lésions trouvées dans les les reins des rats examinés semble être plus en rapport avec le sérotypeicterohaemorrhagiae qu'avec le sérotypepomona. L'importance du sérotypeicterohaemorrhagiae chez le porc de la Cauca Valley est encore à vérifier.

     

Filarial infection of equidae in the Tehran area of Iran

Summary Microfilariae of three genera, namelyElaeophora böhmi, Onchocerca cervicalis andParafilaria multipapillosa were recovered from blood samples of equidae in Tehran, Iran. These microfilarial infections in equidae are reported for the first time from Iran.

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Infestacion Filaroidea De Equinos En El Area De Teheran, Iran

Resumen Microfilarias de tres géneros,Elaeophora bohmi, Onchocerca cervicalis andParafilaria multipapillosa se aislaron de la sangre de equinos en el area de Teherán, Irán. Este es el primer reporte de la infestación filaroidea de equinos en Irán.

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Filariose Des Equides Dans La Region De Teheran En Iran

Résumé Les microfilaires des genresElaeophora böhmi, Onchocerca cervalis etParafilaria multipapillosa ont été trouvées dans des échantillons de sang d'équidés de la région de Téhéran en Iran. C'est la première fois qu'un tel parasitisme des équidés est constaté en Iran.

     

Serological prevalence of bovine babesiosis in Mali

Summary A serological survey of cattle in Mali was carried out to determine the prevalence of antibody activity toBabesia bovis andB. bigemina. It was found that the level ofB. bovis infection as indicated by antibody activities was too low to be of immediate concern. However, the serological prevalence ofB. bigemina was high and this may indicate a potential disease problem. It was also found that when zebu and N'Dama cattle grazed together the N'Dama were twice as likely to have positive titres toBabesia as were the zebus.

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Prevalencia Serologica De Babesiosis Bovina En Mali

Resumen Se llevó a cabo un análisis serológico en Malí, para detectar la prevalencia deBabesia bovis yBabesia bigemina. Se encontró, que la prevalencia serológica deB. bovis es baja para considerar la enfermedad una amenaza inmediata. Sinembargo, la prevalencia deB. bigemina fué alta, un problema potencial. Tambien se encontró, que cuando el ganado Cebu y N'Dama pastorea junto, el N'Dama presenta el doble de títulos serológicos deB. bigemina.

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Frequence Serologique De La Babesiose Bovine Au Mali

Résumé Une enquête sérologique sur le bétail au Mali a été effectuée pour déterminer la fréquence de l'activité des anticorps àBabesia bovis etB. bigemina. On a trouvé que le degré d'infection àB. bovis tel qu'indiqué par les réactions anticorps était trop faible pour constituer un souci immédiat. Cependant la fréquence sérologique deB. bigemina était élevée, ce qui peut indiquer un problème pathologique potentiel. On a aussi noté que lorsque les zébus et les N'Dama broûtaient ensemble, les N'Dama avaient deux fois plus de chance d'avoir des titres positifs àBabesia que ne l'avaient les zébus.

     

Effects of forage ensiling and ration fermentation on total mixed ration pH,ruminal fermentation and performance of growing Holstein‐Zebu cross steers

Our objective was to determine the effect of forage ensiling and ration fermentation on total mixed ration pH, ruminal fermentation and animal performance. Thirty Holstein‐Zebu cross steers were allotted to feeding treatments for 188 days in a randomized complete block design including: fresh grass‐total mixed ration (GTMR; pH 4.7), grass silage‐TMR (STMR; pH 4.0) and fermented‐TMR (FTMR; pH 3.5). Average daily gain for STMR was greatest during the first 3 months period; however, that for FTMR tended to be greater than GTMR during the second 3 months period (P < 0.10). During the second period dry matter intake for STMR was the greatest (P < 0.01), but feed conversion ratio (P < 0.01) and cost per gain (P < 0.01) were the least for FTMR. Protein digestibility tended (P < 0.10) to be greater for FTMR than STMR and fat digestibility was greater (P < 0.05) for GTMR and FTMR than STMR. FTMR had less (P < 0.01) ruminal NH₃‐N content than STMR. Total volatile fatty acids post‐feeding was greatest for GTMR (P < 0.01). Ruminal proportions of acetic and butyric acids were greater for FTMR than GTMR (P < 0.05); in contrast, propionic acid was greater for GTMR (P < 0.05). Utilizing silage or total ration fermentation did not negatively impact on ruminal pH. STMR and FTMRs can be used to maintain performance of growing crossbred Holstein steers.