ABSTRACT Nematode parasites have developed resistance to anthelmintics. Biological control of gas... more ABSTRACT Nematode parasites have developed resistance to anthelmintics. Biological control of gastrointestinal nematodes (GIN) in sheep is a promising non-chemical control method. Two experiments were done using Merino sheep. In each Experiment, gender, initial egg count per g (EPG) and initial live weight (BW) aided in placing animals into four groups, each of which was randomly fed with one of four treatments. Exp 1 evaluated anthelmintic effects of Bacillus thuringiensis Berliner (Bt),Clonostachys rosea f. rosea Schroers (C. rosea) and diatomaceous earth (DE) in sheep. Bacillus thuringiensis and C. rosea were fed to sheep at a rate of 1g kg-1 BW, and DE was fed at 2% of sheep diet. Relative to the control, treatments had no effect (P>0.05) on EPG, but reduced (P<0.001) larvae per gram (LPG) in faecal culture. Efficacy varied with time (P<0.001). On Day 7, Bt, C. rosea and DE had efficacies of 76, 87 and 61%, respectively. In Exp. 2, efficacy of feeding 1g kg-1 BW of C. rosea chlamydospores to sheep every day, every second day and every third day was tested. Daily feeding of fungal chlamydospores had no effect on EPG (P>0.05), but reduced (P<0.001) LPG (12±1.67) more than every second day (39±0.77) or third day (58±1.77). On Day 12, feeding daily, every second day and every third day had efficacies of 90, 63 and 49%, respectively. These studies suggest that each of Bt, C. rosea isolates and DE products has a potential to affect nematode larvae, and daily use of C. rosea had the highest effect as a biological control of nematodes in this study.
"BACKGROUND: The study was conducted to investigate the effects of season, species and PEG additi... more "BACKGROUND: The study was conducted to investigate the effects of season, species and PEG addition on gas production (GP) and GP kinetics parameters by in vitro incubating (72hrs) of five plant species from sub-humid subtropical savannah of South Africa. Plant species used were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata, of which leaves were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. Automated in vitro gas production technique was used in two experiments carried out with nine replicates. The first experiment was to test the effect of season and species, while the second experiment tested the effect of tannins using polyethylene glycol 4000 (PEG). The PEG treatment was applied to samples in early and late wet season.
RESULTS: There were wide variations among seasons and species in crude protein (CP), natural (NDF), acid detergent fibre (ADF) and condensed tannins (CT). Seasons and species affected the maximum GP and GP kinetics parameters. During the three seasons, Chromolaena odorata had the highest CP (186–226 g kg-1 DM), GP (87–104 ml g-1 DM), and GP from soluble (48–53 ml) and insoluble (40–51 ml) fractions, and S. myrtina had the lowest CP (105–129 g kg-1 DM). Acacia natalitia, D. cinerea and S. myrtina had the lowest GP (3, 5 and 2 ml) from soluble fraction during dry, early wet and late wet seasons, respectively. Dichrostachys cinerea had the lowest GP (21 and 33 ml) from insoluble fraction during dry and late wet seasons, respectively, and A. nilotica (6 ml) in early wet season. The maximum GP, its degradation rate and GP soluble fraction were positively correlated to CP without (0.82, 0.74 and 0.82, respectively) and with (0.77, 0.79 and 0.80, respectively) PEG. With PEG, GP from soluble fraction was negatively correlated to NDF, ADL and CT; and without PEG, negatively correlated to CT.
CONCLUSION: Seasons and species affected the gas production parameters. The addition of PEG emphasizes that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata; confirming that these browse species can be used as feed supplements."
Introduction Anthelminthic have been used as effective control for nematode parasites in sheep fo... more Introduction Anthelminthic have been used as effective control for nematode parasites in sheep for decades. Parasites are developing resistance in number of countries (Schnyder et al., 2005; Cringoli et al., 2007). In addition, high costs and limited availability of anthelminthic (Akhtar and Malik, 2000), gives a clear idea that control strategies based exclusively on their use are not sustainable. Currently, screening of medicinal plants alternative is an increasing interest. The aim of this study was to evaluate the effect of ethanol extract from five medicinal plants Ananas comosus, Aloe ferox, Allium sativum, Lespedeza cuneata and Warburgia salutaris on egg production and L3 larvae of nematodes in sheep. Materials and methods This study was conducted using 48 sheep with initial live weight 33.7 ± 11kg. Animals were sorted by sex, initial eggs per gram of faeces and initial weight to six groups of eight sheep each. Each group was then randomly assigned to six treatments; combinat...
Effect of season and plant species on in sacco dry matter (DM) and crude protein (CP) degradabili... more Effect of season and plant species on in sacco dry matter (DM) and crude protein (CP) degradability of five plant species were investigated. Plant species were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata. Leaves were harvested during dry, early wet and late wet seasons, subjected to degradation in cows’ rumen using nylon bags technique. Season affected potential DM degradability and effective degradation of DM and CP. Species affected all parameters except slowly degradable fraction of CP. Interaction between season and species affected the parameters except potential and slowly degradable fraction of CP. Chromolaena odorata had highest estimated parameters of degradation among seasons compared to others. Based on potential and effective degradation, plants followed this decreasing order: C. odorata, A. nilotica, A. natalitia, S. myrtina and D. cinerea. These plants have a potential as feed supplements. Chromolaena odorata has the...
Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five... more Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five plant species from sub-humid subtropical savannah of South Africa were investigated. Leaves of Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. An in vitro technique (72hrs incubating time) was used in two experiments carried out with nine replicates (3 runs x 3 replicates). Experiment 1, tested the effects of season and browse species, while experiment 2, tested the effect of condensed tannins using PEG (4000) on an in vitro degradability of the forages. Season and species affected the true degradability (TrDeg), short chain fatty acids (SCFA) and partitioning factor (PF). TrDeg ranged from 684 to 856 g/kg dry matter (DM). Total SCFA varied (P<0.05) among seasons and browse species. Addition of PEG decreased TrDeg and PF but incr...
Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five... more Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five plant species from sub-humid subtropical savannah of South Africa were investigated. Leaves of Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. An in vitro technique (72hrs incubating time) was used in two experiments carried out with nine replicates (3 runs x 3 replicates). Experiment 1, tested the effects of season and browse species, while experiment 2, tested the effect of condensed tannins using PEG (4000) on an in vitro degradability of the forages. Season and species affected the true degradability (TrDeg), short chain fatty acids (SCFA) and partitioning factor (PF). TrDeg ranged from 684 to 856 g/kg dry matter (DM). Total SCFA varied (P<0.05) among seasons and browse species. Addition of PEG decreased TrDeg and PF but incr...
Nematode resistance to anthelmintic drugs is affecting small ruminant production in South Africa.... more Nematode resistance to anthelmintic drugs is affecting small ruminant production in South Africa. This study evaluated the effect of wattle tannins as an alternative nematode control drench. Two experiments (Exp) were conducted to determine the effect of tannin concentration (Exp 1) and frequency of dosing (Exp 2) on nematode parasites. In each experiment gender, egg count (egg per gram, EPG) and initial live weight aided in blocking sheep into groups, within which they were randomly allocated to and drenched with different tannin treatments. In experiment one, 24 sheep (16 females and 8 males, aged 8-9 months) were placed into four treatment: 0, 0.8, 1.6 and 2.4 g tannin/kg BW; they were drenched for three consecutive days in a study that lasted for 21 days. In Experiment 2, 26 sheep (11 males and 15 females aged 9 to 18 months) were placed into three treatments of 9, 9, and 8 sheep each. These treatments were drenched with 1.6 g tannins/kg BW/day for one day, two or three days for...
The potential of using fungi to prevent nematodosis caused by parasites with free-living larval s... more The potential of using fungi to prevent nematodosis caused by parasites with free-living larval stages is well documented today. In this respect Duddingtonia flagrans, a net-trapping, nematode-destroying fungus, appears to be the most promising candidate. Laboratory experiments and in-vivo studies, where fungal spores have survived passage through the gastro-intestinal tract of cattle and horses, plus field studies with cattle, horses and pigs, demonstrate significant reduction in the number of infective larvae that develop in the faecal environment. In field trials this reduction subsequently leads to reduced infectivity of herbage and also reduced worm burdens in grazing animals. A status of the present situation, primarily based upon work performed in Denmark within the last 6-8 years, plus an outlook for practical implementation of an integrated control strategy including the use of nematode-destroying fungi in the future is discussed.
ABSTRACT Nematode parasites have developed resistance to anthelmintics. Biological control of gas... more ABSTRACT Nematode parasites have developed resistance to anthelmintics. Biological control of gastrointestinal nematodes (GIN) in sheep is a promising non-chemical control method. Two experiments were done using Merino sheep. In each Experiment, gender, initial egg count per g (EPG) and initial live weight (BW) aided in placing animals into four groups, each of which was randomly fed with one of four treatments. Exp 1 evaluated anthelmintic effects of Bacillus thuringiensis Berliner (Bt),Clonostachys rosea f. rosea Schroers (C. rosea) and diatomaceous earth (DE) in sheep. Bacillus thuringiensis and C. rosea were fed to sheep at a rate of 1g kg-1 BW, and DE was fed at 2% of sheep diet. Relative to the control, treatments had no effect (P&amp;gt;0.05) on EPG, but reduced (P&amp;lt;0.001) larvae per gram (LPG) in faecal culture. Efficacy varied with time (P&amp;lt;0.001). On Day 7, Bt, C. rosea and DE had efficacies of 76, 87 and 61%, respectively. In Exp. 2, efficacy of feeding 1g kg-1 BW of C. rosea chlamydospores to sheep every day, every second day and every third day was tested. Daily feeding of fungal chlamydospores had no effect on EPG (P&amp;gt;0.05), but reduced (P&amp;lt;0.001) LPG (12±1.67) more than every second day (39±0.77) or third day (58±1.77). On Day 12, feeding daily, every second day and every third day had efficacies of 90, 63 and 49%, respectively. These studies suggest that each of Bt, C. rosea isolates and DE products has a potential to affect nematode larvae, and daily use of C. rosea had the highest effect as a biological control of nematodes in this study.
"BACKGROUND: The study was conducted to investigate the effects of season, species and PEG additi... more "BACKGROUND: The study was conducted to investigate the effects of season, species and PEG addition on gas production (GP) and GP kinetics parameters by in vitro incubating (72hrs) of five plant species from sub-humid subtropical savannah of South Africa. Plant species used were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata, of which leaves were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. Automated in vitro gas production technique was used in two experiments carried out with nine replicates. The first experiment was to test the effect of season and species, while the second experiment tested the effect of tannins using polyethylene glycol 4000 (PEG). The PEG treatment was applied to samples in early and late wet season.
RESULTS: There were wide variations among seasons and species in crude protein (CP), natural (NDF), acid detergent fibre (ADF) and condensed tannins (CT). Seasons and species affected the maximum GP and GP kinetics parameters. During the three seasons, Chromolaena odorata had the highest CP (186–226 g kg-1 DM), GP (87–104 ml g-1 DM), and GP from soluble (48–53 ml) and insoluble (40–51 ml) fractions, and S. myrtina had the lowest CP (105–129 g kg-1 DM). Acacia natalitia, D. cinerea and S. myrtina had the lowest GP (3, 5 and 2 ml) from soluble fraction during dry, early wet and late wet seasons, respectively. Dichrostachys cinerea had the lowest GP (21 and 33 ml) from insoluble fraction during dry and late wet seasons, respectively, and A. nilotica (6 ml) in early wet season. The maximum GP, its degradation rate and GP soluble fraction were positively correlated to CP without (0.82, 0.74 and 0.82, respectively) and with (0.77, 0.79 and 0.80, respectively) PEG. With PEG, GP from soluble fraction was negatively correlated to NDF, ADL and CT; and without PEG, negatively correlated to CT.
CONCLUSION: Seasons and species affected the gas production parameters. The addition of PEG emphasizes that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata; confirming that these browse species can be used as feed supplements."
Introduction Anthelminthic have been used as effective control for nematode parasites in sheep fo... more Introduction Anthelminthic have been used as effective control for nematode parasites in sheep for decades. Parasites are developing resistance in number of countries (Schnyder et al., 2005; Cringoli et al., 2007). In addition, high costs and limited availability of anthelminthic (Akhtar and Malik, 2000), gives a clear idea that control strategies based exclusively on their use are not sustainable. Currently, screening of medicinal plants alternative is an increasing interest. The aim of this study was to evaluate the effect of ethanol extract from five medicinal plants Ananas comosus, Aloe ferox, Allium sativum, Lespedeza cuneata and Warburgia salutaris on egg production and L3 larvae of nematodes in sheep. Materials and methods This study was conducted using 48 sheep with initial live weight 33.7 ± 11kg. Animals were sorted by sex, initial eggs per gram of faeces and initial weight to six groups of eight sheep each. Each group was then randomly assigned to six treatments; combinat...
Effect of season and plant species on in sacco dry matter (DM) and crude protein (CP) degradabili... more Effect of season and plant species on in sacco dry matter (DM) and crude protein (CP) degradability of five plant species were investigated. Plant species were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata. Leaves were harvested during dry, early wet and late wet seasons, subjected to degradation in cows’ rumen using nylon bags technique. Season affected potential DM degradability and effective degradation of DM and CP. Species affected all parameters except slowly degradable fraction of CP. Interaction between season and species affected the parameters except potential and slowly degradable fraction of CP. Chromolaena odorata had highest estimated parameters of degradation among seasons compared to others. Based on potential and effective degradation, plants followed this decreasing order: C. odorata, A. nilotica, A. natalitia, S. myrtina and D. cinerea. These plants have a potential as feed supplements. Chromolaena odorata has the...
Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five... more Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five plant species from sub-humid subtropical savannah of South Africa were investigated. Leaves of Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. An in vitro technique (72hrs incubating time) was used in two experiments carried out with nine replicates (3 runs x 3 replicates). Experiment 1, tested the effects of season and browse species, while experiment 2, tested the effect of condensed tannins using PEG (4000) on an in vitro degradability of the forages. Season and species affected the true degradability (TrDeg), short chain fatty acids (SCFA) and partitioning factor (PF). TrDeg ranged from 684 to 856 g/kg dry matter (DM). Total SCFA varied (P<0.05) among seasons and browse species. Addition of PEG decreased TrDeg and PF but incr...
Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five... more Effects of season, browse species and polyethylene glycol (PEG) on in vitro digestibility of five plant species from sub-humid subtropical savannah of South Africa were investigated. Leaves of Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata were harvested during dry (June/July), early wet (November/December) and late wet (February/March) seasons. An in vitro technique (72hrs incubating time) was used in two experiments carried out with nine replicates (3 runs x 3 replicates). Experiment 1, tested the effects of season and browse species, while experiment 2, tested the effect of condensed tannins using PEG (4000) on an in vitro degradability of the forages. Season and species affected the true degradability (TrDeg), short chain fatty acids (SCFA) and partitioning factor (PF). TrDeg ranged from 684 to 856 g/kg dry matter (DM). Total SCFA varied (P<0.05) among seasons and browse species. Addition of PEG decreased TrDeg and PF but incr...
Nematode resistance to anthelmintic drugs is affecting small ruminant production in South Africa.... more Nematode resistance to anthelmintic drugs is affecting small ruminant production in South Africa. This study evaluated the effect of wattle tannins as an alternative nematode control drench. Two experiments (Exp) were conducted to determine the effect of tannin concentration (Exp 1) and frequency of dosing (Exp 2) on nematode parasites. In each experiment gender, egg count (egg per gram, EPG) and initial live weight aided in blocking sheep into groups, within which they were randomly allocated to and drenched with different tannin treatments. In experiment one, 24 sheep (16 females and 8 males, aged 8-9 months) were placed into four treatment: 0, 0.8, 1.6 and 2.4 g tannin/kg BW; they were drenched for three consecutive days in a study that lasted for 21 days. In Experiment 2, 26 sheep (11 males and 15 females aged 9 to 18 months) were placed into three treatments of 9, 9, and 8 sheep each. These treatments were drenched with 1.6 g tannins/kg BW/day for one day, two or three days for...
The potential of using fungi to prevent nematodosis caused by parasites with free-living larval s... more The potential of using fungi to prevent nematodosis caused by parasites with free-living larval stages is well documented today. In this respect Duddingtonia flagrans, a net-trapping, nematode-destroying fungus, appears to be the most promising candidate. Laboratory experiments and in-vivo studies, where fungal spores have survived passage through the gastro-intestinal tract of cattle and horses, plus field studies with cattle, horses and pigs, demonstrate significant reduction in the number of infective larvae that develop in the faecal environment. In field trials this reduction subsequently leads to reduced infectivity of herbage and also reduced worm burdens in grazing animals. A status of the present situation, primarily based upon work performed in Denmark within the last 6-8 years, plus an outlook for practical implementation of an integrated control strategy including the use of nematode-destroying fungi in the future is discussed.
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RESULTS: There were wide variations among seasons and species in crude protein (CP), natural (NDF), acid detergent fibre (ADF) and condensed tannins (CT). Seasons and species affected the maximum GP and GP kinetics parameters. During the three seasons, Chromolaena odorata had the highest CP (186–226 g kg-1 DM), GP (87–104 ml g-1 DM), and GP from soluble (48–53 ml) and insoluble (40–51 ml) fractions, and S. myrtina had the lowest CP (105–129 g kg-1 DM). Acacia natalitia, D. cinerea and S. myrtina had the lowest GP (3, 5 and 2 ml) from soluble fraction during dry, early wet and late wet seasons, respectively. Dichrostachys cinerea had the lowest GP (21 and 33 ml) from insoluble fraction during dry and late wet seasons, respectively, and A. nilotica (6 ml) in early wet season. The maximum GP, its degradation rate and GP soluble fraction were positively correlated to CP without (0.82, 0.74 and 0.82, respectively) and with (0.77, 0.79 and 0.80, respectively) PEG. With PEG, GP from soluble fraction was negatively correlated to NDF, ADL and CT; and without PEG, negatively correlated to CT.
CONCLUSION: Seasons and species affected the gas production parameters. The addition of PEG emphasizes that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata; confirming that these browse species can be used as feed supplements."
RESULTS: There were wide variations among seasons and species in crude protein (CP), natural (NDF), acid detergent fibre (ADF) and condensed tannins (CT). Seasons and species affected the maximum GP and GP kinetics parameters. During the three seasons, Chromolaena odorata had the highest CP (186–226 g kg-1 DM), GP (87–104 ml g-1 DM), and GP from soluble (48–53 ml) and insoluble (40–51 ml) fractions, and S. myrtina had the lowest CP (105–129 g kg-1 DM). Acacia natalitia, D. cinerea and S. myrtina had the lowest GP (3, 5 and 2 ml) from soluble fraction during dry, early wet and late wet seasons, respectively. Dichrostachys cinerea had the lowest GP (21 and 33 ml) from insoluble fraction during dry and late wet seasons, respectively, and A. nilotica (6 ml) in early wet season. The maximum GP, its degradation rate and GP soluble fraction were positively correlated to CP without (0.82, 0.74 and 0.82, respectively) and with (0.77, 0.79 and 0.80, respectively) PEG. With PEG, GP from soluble fraction was negatively correlated to NDF, ADL and CT; and without PEG, negatively correlated to CT.
CONCLUSION: Seasons and species affected the gas production parameters. The addition of PEG emphasizes that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata; confirming that these browse species can be used as feed supplements."