M. Lema

Reduction of fecal shedding of enterohemorrhagic Escherichia coli O157:H7 in lambs by feeding microbial feed supplement

Enterohemorrhagic Escherichia coli O157:H7, an emerging food-borne pathogen, has been implicated in several outbreaks in the US. Ruminants, including cattle, sheep and deer are reservoirs of E. coli O157:H7 and fecal shedding of the pathogen forms the vehicle of entry into the human food chain. We studied the efficacy of Lactobacillus acidophilus, Streptococcus faecium, a mixture of L. acidophilus and S. faecium and a mixture of L. acidophilus, S. faecium, Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum in reducing fecal shedding of E. coli O157:H7 by sheep experimentally infected with the pathogen prior to administration with the microbials. Following oral inoculation with 10(10)CFU of E. coli O157:H7, 30 Suffolk ram lambs were blocked by body weight (six blocks of five lambs each) and lambs within the block randomly assigned to five groups. The lamb groups were fed daily for 7 weeks a basal diet without microbial supplement (control) or the basal diet with L. acidophilus or with S. faecium or with a mixture of L. acidophilus and S. faecium or with a mixture of L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum. The microbial supplements contained stabilized live naturally occurring bacteria and were mixed with the diet at the rate of 6.0x10(6)CFU per kilogram of diet. Fecal samples were collected weekly and analyzed for E. coli O157:H7 using modified tryptic soy broth with novobiocin as a pre-enrichement broth and cefixim-tellurite sorbitol MacConkey agar (CT-SMAC) as a selective media. E. coli O157:H7 was confirmed by its reaction with O157 and H7 antisera. E. coli O157:H7 was shed continuously and in varying numbers in the feces throughout the 7-week experimental period by all five groups. However, lambs administered a mixture of L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum shed significantly lower (P=0.0211) average number of E. coli O157:H7 (2.3log(10)CFU per gram of feces per week) than the other lamb groups over the entire experimental period. S. faecium supplemented lambs were comparable (P=0.0884) to lambs fed a mixture of L. acidophulus and S. faecium in fecal shedding of the pathogen (3.5 versus 4.4log(10)CFU per gram of feces) but significantly lower (P=0.0001) than the control lambs (5.6log(10)CFU per gram of feces) and those supplemented with L. acidophilus (5.5log(10)CFU per gram of feces). Average daily gain (ADG) and gain to feed ratio (G:F) were significantly improved (P=0.0145) by the mixed culture microbials (163.0g and 0.33 for the control, 186.4g and 0.37 for L. acidophulus, 168.2g and 0.36 for S. faecium, 213.6g and 0.46 for L. acidophulus and S. faecium, and 219.1g and 0.44, respectively for L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum supplemented lambs. The study indicates that supplementing lambs infected with E. coli O157:H7 with S. faecium or a mixture of S. faecium, L. acidophilus, L. casei, L. fermentum and L. plantarum in the diet can reduce total number of E. coli O157:H7 shed in the feces and improve animal meat production performance as well.

Nutrient content and in vitro dry matter digestibility of silages made from various grain sorghum and sweet sorghum cultivars.

ABSTRACT In the tropics, sorghum is an important grain and forage crop. However, information on silage made from various cultivars including nutrient content and digestibility for livestock is not available. Therefore, silages made from eleven grain sorghum (Sorghum bicolor [L.] Moench) and ten sweet sorghum varieties were studied to determine the effect of sorghum variety and type on nutrient content and in vitro dry matter digestibility (IVDMD). Silage samples were analyzed for Ca, P, Mg, K, Mg, crude protein (CP), ether extract (EE), gross energy (GE), neutral-detergent fiber (NDF), acid-detergent fiber (ADF), cellulose, acid-detergent lignin (ADL) and IVDMD. Results from silage analysis revealed significant (P < 0.05) varietal differences in CP, Ca, P, Mg, K, Na, GE, ash, NDF, ADL, cellulose, hemicellulose contents and IVDMD among grain sorghum varieties. However, the silage values for EE and NDF contents were not significantly different. Similarly, sweet sorghum varieties were significantly different (P < 0.05) in all of the above variables. Among sorghums, grain sorghum silage had higher (P < 0.05) CP, Ca, P, K, Na and IVDMD and lower (P < 0.05) NDF, ADF, cellulose and GE than sweet sorghum silage.

Evaluation of Small Grain Cultivars for Forage in North Alabama

ABSTRACT Field trials were conducted in 2001 and 2002 at two locations in north Alabama to evaluate the forage yield and quality of six triticale (X Triticosecale Wittmack) cultivars (TCL105, TCL111, TX98D955, TX96VT5019, Tritical 498 and Tritical 2700), two wheat (Triticum aestivum L.) cultivars (Jackson and Roberts) and two rye (Secale cereale L.) cultivars (Maton and Oklon). The rye cultivars Maton and Oklon produced the highest (P < 0.05) forage dry matter (DM) at one of the locations in both years. At both locations, TCL105, TCL111 and Tritical 498 produced the lowest (P < 0.05) total forage DM. Crude protein, ether extract and gross energy were lower (P < 0.05) for TCL111 and TCL105. Acid-detergent fiber content was higher (P < 0.05) for TCL 105. Maton, Oklon, Tritical 2700, Tritical 498, TX96VT5019 and TX98D955 had higher (P < 0.05) in vitro dry matter digestibility than TCL105, TCL111, Jackson and Roberts. Maton, Oklon, Tritical 498, TX96VT5019, TX98D955, Roberts and Jackson were higher (P < 0.05) in P content than TCL105, TCL111 and Tritical 2700. Calcium content of TCL105, TCL111, TX96VT5019 and TX98D955 was higher (P < 0.05) than that of Maton, Oklon, Tritical 2700, Tritical 498, Jackson and Roberts. Similarly, significant differences were observed among cultivars in Mg, K, S, Zn, Fe and Cu content.

Growth Rate, Carcass Trait and Blood Chemistry of Cross-bred Meat Goats Grazing Puna Chicory, Rackmaster Refuge Mix and Sahara Bermudagrass

Abstract Lema, M., Kebe, S. and Opio, R. 2008. Growth rate, carcass trait and blood chemistry of cross-bred meat goats grazing Puna chicory, rackmaster refuge mix and Sahara bermudagrass. J. Appl. Anim. Res., 33: 1–6. A grazing trial was conducted to evaluate Puna chicory (Cichorium intybus L.), Rackmaster Refuge Mix [a blend of chicory, mustard (Sinapis alba), turnips (Brassica rapa), clover (Trifolium repens), kale (Brassica oleracea) and rape (Brassica napus)] and Sahara bermudagrass (Cynodon dactylon) as summer pasture for meat goats. Puna chicory and Rackmaster refuge were higher in crude protein (CP), net energy lactation (NE1), net energy gain (NEg), total digestible nutrient (TDN), relative feed value (RFV), Ca, P, Mg and K contents and lower (P<0.05) in ADF than Sahara bermudagrass. Puna chicory was higher (P<0.05) in P, K and Mg than Rackmaster refuge. Rackmaster refuge was higher (P<0.05) than Puna Chicory in TDN and RFV. But Puna chicory supported better performance in terms of average daily gain, live weight gain per ha, dressing percentage and carcass characteristics as compared to Sahara bermudagrass, Rackmaster refuge mix being in between. It is concluded that Puna chicory may result in improved goat productivity in terms of growth rate and chevon production if used as a summer pasture.

Growth and Carcass Characteristics of French Guinea Broilers Fed Diets with Varying Concentrations of Metabolizable Energy

ABSTRACT The potential for guinea fowl (Numida meleagris) production in the US as alternative poultry is a promising enterprise. However, scientific literature on their nutrient requirements is very limited. The objective of this study was to evaluate optimum dietary metabolizable energy (ME) for growth performance and carcass characteristics of French guinea broilers. Two hundred and twenty straight-run day old French guinea keets were randomly assigned to starter diets varying in ME concentration (2800, 2900, 3000, 3100 or 3200 ME kcal/kg diet) with identical crude protein (CP) content (23%) from hatch to 4 weeks of age (WOA). From 5-8 WOA, the diets were formulated to contain 2850, 2950, 3050, 3150 or 3250 ME kcal/kg diet, respectively, and 21% CP. Each 100 ME kcal/kg increase was associated with significant (P < 0.05) decrease in feed consumption such that birds on 2900 and 3000 ME Kcal/kg diet consumed 2.5 and 1.8% less feed than birds on 2800 and 2900 ME kcal/kg diet, respectively. Birds on 3100 and 3200 ME kcal/kg diet were more than 10% heavier (P < 0.05) than birds receiving diets of lower ME. Mean feed conversion ratio (FCR) of birds on 3100 and 3200 ME kcal/kg diet was lower (P < 0.05) than for birds on 3000 and 2900 ME kcal/kg diet. Mean eviscerated carcass weight was higher (P < 0.05) in guinea broilers receiving 3100 ME kcal/kg diet than other treatment groups. The weight of breast, thigh and drumstick of birds on 3100 and 3200 ME kcal/kg diet were not different, but were higher than all other treatment groups. While abdominal fat weight was directly proportional to dietary metabolizable energy levels, differences in weights of heart, liver and gizzard were not significant among the dietary metabolizable energy levels. Positive and highly significant correlations (P < 0.01) were noted between live weight and weight of carcass, breast, thigh and drumstick of French guinea broilers. Thus, based on this study, at 21% CP levels French guinea broilers will utilize more efficiently diets containing 3100 and 3150 ME kcal/kg diet at 0-4 and 5-8 WOA, respectively.

Lamb production and forage quality under a forage system consisting of AU Triumph tall fescue and Tifton 44 bermudagrass

The lamb production potential and forage quality of a forage system consisting of AU Triumph fescue and Tifton 44 bermudagrass was studied over a period of two consecutive years. Each spring, 60 yearling Suffolk ewes and 40 wethers were divided into two groups and allowed to graze two replicated 1ha AU Triumph paddocks continuously. At the end of the spring grazing season, both groups were transferred to two replicated 1ha Tifton 44 paddocks for summer grazing. Body weight was recorded fortnightly and composite forage samples analyzed for chemical composition, in vitro dry matter disappearance (IVDMD) and in vitro organic matter disappearance (IVOMD) at the end of the study. Mean crude protein (CP), ether extract (EE), ash, neutral-detergent fiber (NDF), acid-detergent fiber (ADF), cellulose, lignin, IVDMD and IVOMD contents of AU Triumph fescue were 13.26, 1.86, 7.38, 69.4, 36.37, 29.2, 6.81, 64.44 and 62.88%, respectively. The corresponding values for Tifton 44 bermudagrass were 7.5, 1.01, 5.2, 78.3, 41.0, 28.3, 8.8, 56.97 and 55.61%. Average daily gain (ADG) and lamb gain per hectare on AU Triumph fescue were 142.1g and 412.59kg/ha, respectively. However, lamb ADG started to decline and remained low when they were transferred from AU Triumph to Tifton 44 bermudagrass resulting in a low ADG and lamb gain per hectare of only 18.2g and 84.09kg/ha, respectively. In contrast, Tifton 44 yielded higher post grazing residual DM, suggesting that the decline in performance of the lambs grazing Tifton 44 to be related to poor forage quality rather than availability. The results indicate that low nutritive value of Tiftton 44 bermudagrass is a limiting factor to lamb production in the forage system studied. To prevent the observed decline in lamb performance, it might be necessary to fertilize Tifton 44 at a higher rate or replace it with a better quality warm season forage.

Evaluation of Cultivated Summer Pastures for Meat Goats in Tennessee

Abstract Lema, M., Kebe, S., Opio, R. and Fenderson, C. 2006. Evaluation of cultivated summer pastures for meat goats in Tennessee. J. Appl. Anim. Res., 30: 57–62. A grazing trial was conducted to evaluate Puna forage chicory (Cichorium intybus L.), hybrid Penleaf pearl millet (Pennisetum glaucum) and Sahara bermudagrass (Cynodon dactylon) as summer pasture for meat goats. Puna chicory was 28.3 and 67.7% higher (P<0.05) in crude protein (CP), 28.1 and 35.4% lower (P<0.05) in acid detergent fiber (ADF) and 40.0 and 46.0% lower (P<s0.05) in neutral detergent fiber (NDF) than Penleaf pearl millet and Sahara bermudagrass, respectively. Relative feed value (RFV), Ca, P, Mg and K contents were significantly higher (P<0.01) for Puna chicory than for Penleaf pearl millet and Sahara bermudagrass. Penleaf pearl millet was higher (P<0.01) than Sahara bermudagrass in P, K and Mg content. Puna chicory and Pearl millet produced 73 and 70% higher (P<0.05) forage CP per ha, respectively than Sahara bermudagrass. Average daily gain (ADG) and live weight gain per ha of does grazing Puna chicory were significantly higher (P<0.05) than those grazing Sahara bermudagrass does and Penleaf pearl millet. It is concluded that Puna chicory is a better fodder than Penleaf pearlmillet and Sahara bermudagrass.

Nutrient Content and In Vitro Dry Matter Digestibility of Silages Made From Various Sweet Sorghum Cultivars

Abstract Lema, M., Felix, A., Salako, S. and Bishnoi, U. 2001. Nutrient content and in vitro dry matter digestibility of silages made from various sweet sorghum cultivars. J. Appl. Anim. Sci., 20: 99–106. Sweet sorghum is an important forage crop in the tropics. Silages made from ten sweet sorghum varieties were studied to determine the effect of variety on nutrient content and in vitro dry matter digestibility (IVDMD). Results from silage analysis revealed significant (P<0.05) varietal differences in crude protein (CP), Ca, P, Mg, K, Na, gross energy (GE), ash, neutral-detergent fiber (NDF), acid-detergent lignin (ADL), cellulose, hemicelluiose contents and IVDMD among sweet sorghum varieties.

Forage Production and Quality of Triticale Cultivars in the Tennessee Valley

ABSTRACT Because of its cold tolerance and double-cropping potential, triticale can play an important role in sustainable agriculture in the Tennessee Valley by bridging the feed shortage gap in late fall and winter when other cool season grasses become dormant. Field trials were conducted in 2001 and 2002 at two locations in the Tennessee Valley to evaluate the forage yield and quality of six triticale (X Triticosecale Wittmack) cultivars (TCL105, TCL111, TX98D955, TX96VT5019, Tritical 498 and Tritical 2700). At both locations, TX98D955, TX96VT5019 and Tritical 2700 produced higher (P < 0.05) forage dry matter than the other cultivars. Crude protein and gross energy contents and in vitro dry matter digestibility were lower (P < 0.05) and acid-detergent fiber content higher (P < 0.05) for the cultivar TCL105 than the other cultivars. The cultivars TX96VT5019 and TX98D955 had higher (P < 0.05) P content and the cultivars TCL105, TCL111, TX96VT5019 and TX98D955 had higher (P < 0.05) Ca content than the rest. The cultivars TCL105 and TCL111 were higher (P < 0.05) in Mg and lower (P < 0.05) in K than the other cultivars. Sulfur was higher (P < 0.05) for Tritical 498 and Zn higher (P < 0.05) for TCL498, TX96VT5019 and TX98D955. Iron content was lower (P < 0.05) for TX96VT5019 and TX98D955 than for the other cultivars. The results of the study will provide useful guidelines for livestock producers for comparing triticale cultivars for forage in the Tennessee Valley.

Regression Analysis for Predicting AU Triumph Tall Fescue Forage Quality from Chemical Composition Data in North Alabama

Abstract Lema, M., Knox, N. and Walker, L. 2002. Ṙegression analysis for predicting AU Triumph tall fescue forage quality from chemical composition data in North Alabama. J. Appl. Anim. Res., 22: 81–90. Statistical models may be better alternatives for forage quality estimation as chemical analysis, near infrared reflectance spectroscopy (NIRS) and in vitro digestion are in most instances time-consuming, expensive and hard to obtain and some times utilize hazardous chemicals. A study was conducted to calibrate AU Triumph tall fescue (Festuca arundinacea Shreb) forage quality (WDMD, NDF, ADF and CP contents) predictive equations from chemical analysis data. AU Triumph tall fescue pasture samples collected over a 2-year period were analyzed for crude protein (CP), acid-detergent fiber (ADF), neutral-detergent fiber (NDF), ether extract (EE), acid-detergent lignin (ADL), cellulose (CEL), ash and in vitro dry matter digestibility (IVDMD). Quadratic, cubic and logarithmic relations between independent variables and quality parameter were considered and the data subjected to stepwise regression and correlation analysis. The best fitting equation to predict IVDMD and CP contained only NDF (IVDMD-154.97–1.41 NDF, R2=0.92, RMSE=1.99; CP=41.39–0.51 NDF, R2=0.87, RMSE=0.90) while the best equation to predict NDF contained only EE (NDF=86.80–19.03 EE + 2.98 EE2, R2=0.92, RMSE=1.34). Ash and CEL were the best predictors of ADF (ADF=0.47 + 0.14 Ash + 0.96 CEL, R2=0.99, RMSE=0.04). Model validation using independent samples gave correlation coefficients of validation ranging from 0.86 to 0.97. The results show that tall fescue forage quality parameters (TVDMD, NDF, ADF and CP) can be estimated with high accuracy using simple equations requiring one or two chemical determinations. These equations provide convenient alternatives to chemical analysis for estimating tall fescue forage quality in North Alabama.