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Prodrogues Polymères Dégradables par Polymérisation Radicalaire par Ouverture de Cycle Contrôlée par les Nitroxydes / Degradable Polymer Prodrugs by Nitroxide-Mediated Radical Ring-Opening PolymerizationGuegain, Elise 28 November 2017 (has links)
La copolymérisation radicalaire par ouverture de cycle contrôlée par les nitroxydes entre les esters méthacryliques et les acétals de cétène cycliques a permis de synthétiser des copolymères vinyliques bien contrôlés et dégradables contenant des fonctions esters le long de la chaine polymère. Plus précisément, des copolymérisations entre le 2-méthylène-4-phenyl-1,3-dioxolane (MPDL) et l’oligo(éthylène glycol) méthyl éther méthacrylate (OEGMA) ou le méthacrylate de méthyle (MMA) ont été amorcées par une alkoxyamine basée sur le nitroxyde SG1. Des copolymères de type P(OEGMA-co-MPDL) et P(MMA-co-MPDL) ont été obtenus et dégradés hydrolytiquement en conditions accélérées ou physiologiques. Leurs cinétiques de dégradation furent également comparées à celles de polyesters traditionnels (e.g., PLGA, PLA and PCL) où il a été montré que la dégradation des copolymères de P(OEGMA-co-MPDL) pouvait être ajustée par la stœchiométrie initiale en monomères et qu’elle se situait entre celles du PLA et du PCL. En revanche, les copolymères de P(MMA-co-MPDL), plus hydrophobes, ont présenté une hydrolyse très lente, bien inférieure à celle du PCL. Dans un deuxième temps, une nouvelle famille de prodrogues polymères dégradable a été synthétisé par copolymérisation radicalaire par ouverture de cycle contrôlée par les nitroxydes entre le MPDL et l’OEGMA ou le MMA, à partir d’un amorceur couplé à un principe actif (méthode du principe actif amorceur). Pour ce faire, la Gemcitabine, un principe actif anticancéreux, a été couplé à une alcoxyamine à base SG1 qui fut ensuite utilisée pour amorcer la réaction de copolymérisation. Les copolymères ainsi obtenus ont montré des propriétés de libération de la Gem et des activités cytotoxiques sur différentes lignées cellulaires en relation avec la nature de l’ester méthacrylique utilisé, la nature de la liaison entre la Gem et le copolymère ainsi que le taux de MPDL dans le copolymère. Cette étude nous a permis d’extraire des relations de type structure-activité importantes pour des développements futurs. / Nitroxide-mediated radical ring-opening copolymerization of methacrylic esters and cyclic ketene acetals was investigated and enabled the synthesis of well-defined degradable vinyl copolymers containing ester groups along the main chain, whose amount was readily adjusted by changing the initial comonomer feed. More specifically, the copolymerizations of 2-methylene-4-phenyl-1,3-dioxolane (MPDL) and either oligo(ethylene glycol) methyl ether methacrylate (OEGMA) or methyl methacrylate (MMA) were initiated by an alkoxyamine initiator based on the SG1 nitroxide. It led to a library of P(OEGMA-co-MPDL) and P(MMA-co-MPDL) materials that were hydrolytically degraded under both accelerated and physiological conditions. Their hydrolytic degradation kinetics were also benchmarked against traditional polyesters (e.g., PLGA, PLA and PCL) where P(OEGMA-co-MPDL) copolymers showed tunable degradation rates as function of the MPDL content, being in between those of PLA and PCL. Conversely, the more hydrophobic P(MMA-co-MPDL) copolymers exhibited much slower hydrolysis than that of PCL. In a second step, a new class of degradable polymer prodrugs was developed by nitroxide-mediated radical ring-opening copolymerization of MPDL with OEGMA or MMA, from a drug-bearing initiator (‘drug-initiated’ method). To do so, Gemcitabine, an anticancer drug, was derivatized with a SG1-based alkoxyamine to initiate the copolymerization reaction. The resulting degradable polymer prodrugs exhibited interesting characteristics in terms of drug release and in vitro cytotoxicity, depending on the nature of the methacrylic ester used, the nature of the linker between the drug and the polymer and the MPDL content. This study enabled us to extract important structure-activity relationships of great importance for further development.
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Pappersgarn, framtidens fiskenät? / Paper yarn, the fishing net of the future?Alkin, Linnea, Ingerholt, Saga January 2023 (has links)
Textilindustrin är i behov av nya material som kräver mindre resurser än konventionellt använda material som exempelvis syntet- och bomull. Syntetiska material har en negativ påverkan på miljön, bland annat på grund av den mängd mikroplaster som släpps ut i naturen vid produktion och användning (Nagamine, Kobayashi, Kusumi & Wada 2022). En industri där syntetiska material ligger till grund för stora problem för marint liv är fiskeindustrin. När syntetiska nät tappas, oftast tillverkade av polyamid, fortsätter de att fånga fisk som inte tas om hand. Detta fenomen kallas spökfiske och skulle kunna motverkas om de syntetiska näten ersattes med ett naturligt biologiskt nedbrytbart material. Pappersgarn är ett relativt nytt material inom textilindustrin och har många egenskaper som är önskvärda vid användning i ett fiskenät, speciellt det faktum att det är biologiskt nedbrytbart. Denna studie undersöker möjligheten att använda ett pappersgarn i fiskeutrustning, närmare bestämt en kräftmjärde. Studien undersöker tre olika pappersgarn med olika grovlek, det vill säga Tex (92, 218 och 1814). Experiment utförs på garnets draghållfasthet och nedbrytningsförmåga. Ett test i bristningsstyrka görs på nät tillverkade av garnen. Testerna visar att garn med Tex 1814 är det mest lämpliga att använda i en kräftmjärde. Detta garn hade en draghållfasthet, efter 14 dagar i naturligt havsvatten, på 10541 centinewton/tex [cN/tex]. Nätet tillverkat av samma garn hade en genomsnittlig bristningsstyrka på 136 kilopascal [kPa], vilket var över den genomsnittliga bristningsstyrkan för ett nät i polyamid. Om syntetisk fiskeutrustning skulle ersättas med biologiskt nedbrytbart pappersgarn skulle det kunna motverka spökfiske och minska mängden mikroplaster i naturen. / The textile industry is in need of new materials that use less resources than conventionally used material such as synthetics and cotton. Furthermore, synthetic materials have a negative impact on the environment partly due to the amount of micro plastics that are released in nature during production and use (Nagamine, Kobayashi, Kusumi & Wada 2022). One area where synthetic materials are causing a lot of damage is the fishing industry. Synthetic nets that are lost or dropped keep catching fish that are not taken care of. This phenomenon is called ghost fishing and could be solved if the synthetics were replaced with a natural biodegradable material. Paper yarn is a relatively new material in the textile industry and has many properties that are preferred if used in a fishing net, especially the fact that it is biodegradable. This study investigates the possibility of using a paper yarn in fishing gear, more specifically a crayfish trap. The study examines three different paper yarns with different weight, also called Tex (92, 218 and 1814). Experiments are done on the yarn's tensile strength and degradability. A bursting strength test is made on nets made out of the yarns. The tests show that yarn with Tex 1814 is the most suitable to use in a crayfish trap. This yarn had a tensile strength, after 14 days in natural seawater, of 10541 centinewton/tex [cN/tex]. The net made of the same yarn had an average bursting strength of 136 kilopascal [kPa] which was above the average bursting strength of a polyamide net. If synthetic fishing gear would be replaced with biodegradable paper yarn, this could counteract ghost fishing and reduce micro plastics ending up in nature.
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Stimulation of Microbial Protein Synthesis by Branched-Chain Volatile Fatty Acids in Dual Flow Cultures Varying in Forage and Polyunsaturated Fatty Acid ConcentrationsMitchell, Kelly Elizabeth January 2022 (has links)
No description available.
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Effects of Brevibacillus laterosporus and live yeast on rumen fermentation, nutrient digestibility and microbial protein synthesisAdeleke, Rasaq Ademola 11 1900 (has links)
This study investigated the effects of Brevibacillus laterosporus and live yeast (LY) on rumen fermentation, nutrient digestibility and microbial protein synthesis. The basal diet was a total mixed ration formulated to fulfil the minimum nutrient requirement of early lactating 600 kg Holstein cow producing 40kg of milk with 3.5 % fat and 3.3 % protein using CPM-dairy software (NRC, 2001). Treatments were: T1 (Control: basal diet with no additive), T2 (Basal diet + Brevibacillus laterosporus), T3 (Basal diet + Live yeast), and T4 (Basal diet + Brevibacillus laterosporus + Live yeast). In situ degradation, in vitro batch fermentation were performed. Data obtained were subjected to analysis of variance (ANOVA) using PROC GLM (SAS Institute, 2009). The effective dry matter (DM) degradability evaluated at low (0.02) and medium (0.05) ruminal passage rate (ED1 and ED2) were higher (p<0.05) in T1 compared to T2 and T3, but did not differ (p>0.05) between T2, T3 and T4, and between T1 and T4. When evaluated at fast passage rate (0.08) the effective DM degradability (ED3) was higher (p<0.05) in T1 compared to T3 and T4, but did not differ (p>0.05) between T1 and T2. The difference in ammonia nitrogen production was observed only between T1 and T2, and was higher (p<0.05) in T1. The total VFA’s concentration was higher (p<0.05) in T3 compared to the control.
All additives decreased the molar percentage of acetate (P<0.05). The concentration of acetate was lower (p<0.05) in T3 and T4 compared to control. Propionate concentration was higher (p<0.05) in T3 and T4 compared to other treatments and lower (p<0.05) in the control compared to the rest of treatments. Butyrate concentration was higher (p<0.05) in T2 and T4 compared to the rest of the treatments, and lower (p<0.05) in T3 than other treatments. The microbial protein synthesis measured as purine derivate done on residues was higher (p<0.05) for T3 compared to T1 and T2, but did not differ between T1, T2 and T4, and between T3 and T4. These results showed that the two additives have different individual effects on DM and CP degradability, but also associative effects in some fermentation parameters such as propionate production. / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
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Uso de Salinomicina e Virginiamicina na Alimentação de Bovinos de Corte à Pasto no Verão e no Inverno / Use of salinomycin and virginiamycin in feed for beef cattle raised on pasture in summer and winterFerreira, Sérgio Fernandes 21 June 2013 (has links)
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Previous issue date: 2013-06-21 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The aimed was to include virginiamycin and salinomycin to supplement beef cattle
growth in atropical grass base diet during rainy season. Experiment 1: A total of 45
animals, grouping on 15 maleNelore of the same contemporary group, in RBD
distribution; rotational grazing system handled (Panicum maximum cv. Massai).
Variables analyzed were SMC, DWG, biometric measurements, BCS and economic
assessment. Experiment 2: 6 fistulated animals were used, Nellore males of the same
contemporary group, distributed in LSD 3x3 replicated; rotational grazing system
handled (Brachiariadecumbens) from 14h to 10h hours and the MS. Variables analyzed
were MSC, rumen pH, ammonia, DM, NDF and ADF in siturumen degradability. For
both experiments, three treatmentswereconsisted: control, mineral supplement by
COMIGO - Cria61 - F2 (MS); virginiamycin: MS + virginiamycin (Phigrow ®) 100 mg /
animal / day; salinomycin: MS + salinomycin (Posistac ®) 108 mg / animal / day. The
results were analyzed by varianceanalysis and means were compared by Tukey test
(P>05). The group control showed greater MSC (P <0.05), the virginiamycin group
increased 25.4% in DWG (P <0.05), 0.583 kg / animal / day, compared to control (0.465
kg / animal / day), and 9.79% in relation to salinomycin (0.531 kg / animal / day) and
that higher than the control14.2%. There was a reduction of 18.7% in the CSM to
virginiamycin and salinomycin to 29.0% when comparing with the control. The
virginiamycin was handling better financial efficiency: 26% higher than the control and
8.6% higher than salinomycin, and this, 16% higher than the control. There was no
significant difference (P> 0.05) for MSC on rumen pH average(6.66, 6.61 and 6.56) and
ammonia concentration (4,207, 4,238 and 3,892 mg N-NH3 / dL ) respectively for
control, virginiamycin and salinomycin. The results for DM degradability and ADF,
showed no significant difference (P <0.05) for analyzed variables. There was statistical
differencesin NDF degradability (P> 0.05), virginiamycin had the highest degradability in
2 and 5% of passage rates, similar to control and greater than salinomycinin the 8% /
hourrate. The virginiamycin and salinomycin can be linked toSM, however do not
promote significant effects on ruminal pH, ammonia nitrogen values on DM e ADF
degradability. But virginiamycin promoted greater effective degradability of NDF.
The aimed was to include virginiamycin (VM) in two levels to energy-protein supplement
(EPS) for beef cattle growth on a basic diet of tropical grass in the dry season.
Experiment 1: A total of 45 animals were used, in groups of 15 maleNellore of the same
contemporary group, randomly distributed in RB; in rotational grazing system handled
(Tifton 85). Experiment 2: A total of 6 fistulatedNellore males of the same contemporary
group, distributed in LSD 3x3 replicated. Animals were handled in a rotational grazing
system (Brachiariadecumbens) in the dry season. Distributed into three treatments:
control, COMIGO Mineral Supplement - Production - F.10 protein-energy (PES); VM
100: PES + VM (Phigrow ®) 108 mg / animal / day; VM 200: PES + VM (Phigrow® )
216 mg / animal / day. Variables analyzed in in experiment 1 were PESC, DGW,
biometric measurements and BCS and in experiment 2, PESC, rumen pH, ammonia,
DM, NDF and ADF, in situ degradability. Results were analyzed by variance analysis
and means were compared by Tukey test (P>0.05). There was no difference in ADG,
PESC and biometric measurements (P <0.05), ADG for VM 200, 0,431, 0,391 and 100
VM control 0.398 kg / animal / day. There was no significant difference (P> 0.05) for
PESC, in the overall rumen pHaverage (7.02, 7.04 and 7.06) and ammonia
concentration (3,961, 3,876 and 4,147 mg N-NH3 / dL) respectively for control, VM 100
and VM 200 (P> 0.05). There was no significant difference (P <0.05) for any variables in
DM, NDF and ADF degradability analyses. Virginiamycin inclusion caused greater
supplementreduction on cattle on grazing pasture, and did not affect rumen pH, in
rumen ammonia, dry matter and neutral detergent fiber and aciddegradability values. / A virgianamicina é um antibiótico não ionóforo e a salinomicina um antibiótico
carboxílico poliéster ou simplesmente ionóforo, que têm sido usados como
manipuladores ruminais para obtenção de melhores índices zootécnicos. Assim,
objetivou-se avaliar os efeitos no GMD, no consumo de suplemento, nas medidas
biométricas, ECC e na eficiência econômica para 45 bovinos machos inteiros, Nelore
criados em pasto de Panicum maximum CV. Massai no verão e Cynodon spp. no
inverno; no pH ruminal, na concentração de nitrogênio amoniacal, no consumo de
suplemento, na DISMS, DISFDN e DISFDA por 6 bovinos machos Nelore fistulados no
rúmen criados em pasto de Brachiaria decumbens, com a inclusão de virginiamicina ou
salinomicina veiculadas no suplemento mineral no período das águas e no suplemento
proteico-energético no período seco do ano. Os tratamentos no período das águas
foram constituidos: controle, apenas Suplemento Mineral COMIGO – CRIA 61 – F.2
(SM); virginiamicina = SM + virginiamicina (PhiGrow®) 100 mg/animal/dia; salinomicina
= SM + salinomicina (Posistac®) 108 mg/animal/dia; e os tratamentos no período seco
foram constituidos: controle, apenas Suplemento Mineral COMIGO Produção F.10
protéico-energético (SPE); VM 100 = SPE + 108 mg/animal/dia de virginiamicina; VM
200 = SPE + 216 mg/animal/dia de virginiamicina. No período das águas o grupo
controle apresentou maior CSM (P>0,05), o grupo virginiamicina maior (P>0,05) GMD
(0,583), seguido por salinomicina (0,531) e o grupo controle (0,465 kg/animal/dia). As
medidas biométricas não apresentaram diferenças (P>0,05), sugerindo que haja uma
mudança na composição do GMD entre os diferentes tecidos. A virginiamicina foi o
tratamento de melhor eficiência financeira: 26% superior ao controle e 8,6% superior ao
salinomicina, e este, 16% superior ao controle. Para os animais fistulados não houve
diferença (P<0,05) para CSM, mas houve redução para os 3 tratamentos. Não houve
diferença significativa na média global do pH ruminal e nitrogênio amoniacal (mg NNH3/
dL). Os resultados para DISMS e DISFDA, não apresentaram diferenças (P<0,05)
para nenhuma das variáveis analisadas. Na degradabilidade da FDN houve diferenças
estatísticas (P>0,05), a virginiamicina apresentou as maiores degradabilidade efetiva
nas taxas de passagem de 2 e 5%, e semelhante ao controle e maior que salinomicina
na taxa de 8%/hora. Para o período seco não houve diferenças para GMD, CSPE e
para medidas biométricas (P<0,05), GMD para VM 200 de 0,431; VM 100 de 0,391 e
controle de 0,398 kg/animal/dia. O uso de VM ao nível de 216 mg/ animal/ dia
promoveu aumento da eficiência econômica. Para os animais fistulados não houve
diferença (P>0,05) para CSPE, na média global do pH ruminal, 7,02 para controle, 7,04
para VM 100 e 7,06 para VM 200, e nitrogênio amoniacal (mg N-NH3/ dL), 3,961 para
controle, 3,876 para VM 100 e 4,147 para VM 200 (P>0,05. Não houve diferença
significativa (P>0,05) para nenhuma das variáveis analisadas na degradabilidade da
MS, da FDN e da FDA, os valores observados sugerem que é necessário maior
número de repetições para situações similares às realizadas nesta experimentação.
Objetivou-se incluir a virginiamicina e a salinomicina ao suplemento para bovinos de
corte em crescimento com dieta base de gramínea tropical no período das águas.
Experimento 1: foram utilizados 45 animais, grupos de 15 animais machos Nelore de
mesmo grupo contemporâneo, distribuídos em DBC; manejados em sistema de lotação
rotacionada (Panicum maximum cv. Massai). As variáveis analisadas foram o CSM,
GMD, medidas biométricas, ECC e apreciação econômica. Experimento 2: foram
utilizados 6 animais fistulados no rúmen, machos Nelore de mesmo grupo
contemporâneo, distribuídos em DQL 3x3 replicado; manejados em sistema de lotação
rotacionada (Brachiaria decumbens) das 14 às 10 horas e ao SM. As variáveis
analisadas foram o CSM, pH ruminal, nitrogênio amoniacal, degradabilidade ruminal in
situ da MS, FDN e FDA. Para ambos os experimentos, foram constituídos três
tratamentos: controle, apenas suplemento mineral COMIGO – Cria 61 – F2 (SM);
virginiamicina: SM + virginiamicina (Phigrow®) 100 mg/animal/dia; salinomicina: SM +
salinomicina (Posistac®) 108 mg/animal/dia. Os resultados foram interpretados por
meio de análise de variância e as médias comparadas pelo teste de Tukey (P>0,05). O
grupo controle apresentou maior CSM (P<0,05), o grupo virginiamicina acréscimo de
25,4% no GMD (P<0,05), 0,583 kg/ animal/ dia, em relação ao controle (0,465 kg/
animal/ dia), e 9,79% em relação ao salinomicina (0,531 kg/animal/dia), e este 14,2%
superior ao controle. Houve redução de 18,7% no CSM para virginiamicina e 29,0%
para salinomicina ao comparar com o controle. A virginiamicina foi o tratamento de
melhor eficiência financeira: 26% superior ao controle e 8,6% superior ao salinomicina,
e este, 16% superior ao controle. Não houve diferença significativa (P>0,05) para CSM,
na média do pH ruminal (6,66, 6,61 e 6,56) e da concentração de nitrogênio amoniacal
(4,207, 4,238 e 3,892 mg N-NH3/ dL) respectivamente para controle, virginiamicina e
salinomicina. Os resultados para a degradabilidade da MS e FDA, não apresentaram
diferença significativa (P<0,05) para as variáveis analisadas. Na degradabilidade da
FDN houve diferenças estatísticas (P>0,05), a virginiamicina apresentou as maiores
degradabilidade efetiva nas taxas de passagem de 2 e 5%, e semelhante ao controle e
maior que salinomicina na taxa de 8%/hora. A virginiamicina e a salinomicina, podem
ser veiculados ao SM, contudo não promovem efeitos significativos nos valores do pH
ruminal, do nitrogênio amoniacal, na degradabilidade da MS e da FDA. Mas a
virginiamicina promoveu maior degradabilidade efetiva da FDN.
Objetivou-se incluir em dois níveis a virginiamicina (VM), ao suplemento proteicoenergético
(SPE) para bovinos de corte em crescimento com dieta base de gramínea
tropical no período seco do ano. Experimento 1: Foram utilizados 45 animais, grupos
de 15 animais machos Nelore de mesmo grupo contemporâneo, distribuídos
aleatoriamente em DBC; manejados em sistema de lotação rotacionada (Tifton 85).
Experimento 2: Foram utilizados 6 animais fistulados no rúmen, machos Nelore de
mesmo grupo contemporâneo, distribuídos em DQL 3x3 replicado. Os animais foram
manejados em sistema de lotação rotacionada (Brachiaria decumbens) diferida no
período seco do ano. Foram constituídos três tratamentos: controle: apenas
Suplemento Mineral COMIGO – Produção – F.10 proteico-energético (SPE); VM 100:
SPE + VM (Phigrow®) 108 mg/animal/dia; VM 200: SPE + VM (Phigrow®) 216
mg/animal/dia. As variáveis analisadas foram o CSPE, GMD, medidas biométricas e
ECC no experimento 1 e o CSM, pH ruminal, nitrogênio amoniacal, degradabilidade
ruminal in situ da MS, FDN e FDA no experimento 2. Os resultados foram interpretados
por meio de análise de variância e as médias comparadas pelo teste de Tukey
(P>0,05). Não houve diferença para GMD, CSPE e para medidas biométricas (P<0,05),
GMD para VM 200 de 0,431; VM 100 de 0,391 e controle de 0,398 kg/animal/dia. Não
houve diferença significativa (P>0,05) para CSPE, na média global do pH ruminal (7,02,
7,04 e 7,06) e da concentração de nitrogênio amoniacal (3,961; 3,876 e 4,147 mg NNH3/
dL) respectivamente para controle, VM 100 e VM 200 (P>0,05). Não houve
diferença significativa (P<0,05) para nenhuma das variáveis analisadas na
degradabilidade da MS, da FDN e da FDA. A inclusão de virginiamicina promoveu
acentuada redução no consumo do suplemento em bovinos sob pastejo diferido e não
influenciou os valores do pH ruminal, nas concentrações de nitrogênio amoniacal no
rúmen, na degradabilidade da matéria seca e das fibras em detergente neutro ou
ácido.
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Chemical composition, ruminal degradability and in vitro digestibility of dry matter and crude protein of dichrostachys cinerea and bauhinia thonningii leaves.Mahwasane, Mulalo Birgit 18 May 2018 (has links)
MSCAGR (Animal Science) / Department of Animal Science / Forage and browse legumes play an important role in sustaining livestock in small holder
farming systems in the tropics, mainly as a result of their contribution to economic and
environmental sustainability of livestock production. The study was conducted to determine the
chemical composition, ruminal degradability and in vitro digestibility of dry matter (DM) and
crude protein (CP) of Dichrostachys cinerea and Bauhinia thonningii leaves. The browse tree
leaves were harvested in the wild in Shayandima, Limpopo province. The leaves were collected,
oven-dried, milled to pass through a 1.0 mm sieve and analysed for chemical composition in the
Animal Science Nutrition Laboratory, at the University of Venda. The browse tree leaves were
analysed for DM nitrogen, neutral detergent fibre (NDF) and acid detergent fibre (ADF).
Approximately 5 g of leaf sample milled to pass through through a 1 mm sieve were placed in
nylon bags (external dimension: 6 × 12 cm, pore size of 41 μm) and incubated in duplicates for
0, 4, 8, 16, 24, 48, 72, 96 and 120 hours periods in the rumen of three cannulated Bonsmara
steers. The residues were then analysed for DM and nitrogen. Parameters to describe the
dynamics of ruminal degradability of DM and CP were obtained by fitting the data on the
exponential equation P = a + b (1 - e-ct) using NEWAY computer program, where “a” is the rapid
degradable fraction, “b” is the slow degradable fraction and “c” is the outflow rate. The in vitro
DM and CP degradability of rumen undegradable residue collected after 24 and 48 hour
incubation was determined by sequential in vitro digestion in pepsin (abomasal) and pancreatin
(small intestine) solutions. DM and CP content differed significantly (P ˂ 0.05). D. cinerea
leaves had higher levels of DM and CP content than B. thonningii leaves. DM and CP
disappearance increased (P < 0.01) as the incubation period increased. There was no
difference (P > 0.05) in soluble fraction ‘a’ and ‘b’ of DM of the two species. The CP
components for both fraction ‘a’ and ‘b’ differed significantly (P < 0.01) for CP among the two
species. There was significant difference (P < 0.01) in post-ruminal digestibility among the two
species. CP digestibility of B. thonningii and D. cinerea leaves was reduced (P < 0.01). In
conclusion, B. thonningii and D. cinerea leaves showed significant difference based on their
fermentation kinetics and in vitro digestibility, suggesting a good nutritional quality which can be
used as protein source for ruminants in dry season and supplement to low-quality diets. / NRF
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