• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 195
  • 28
  • 4
  • 4
  • 3
  • 1
  • 1
  • Tagged with
  • 251
  • 78
  • 69
  • 61
  • 41
  • 35
  • 33
  • 32
  • 30
  • 29
  • 29
  • 28
  • 27
  • 26
  • 25
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Metabolismo ruminal e balanço de minerais em bubalinos com diferentes níveis de ingestão de fósforo / Rumen metabolism and the mineral balance in water buffaloes with different levels of the phosphorus intake

Nedilse Helena de Souza 26 November 2004 (has links)
Quatro bubalinos adultos com fístulas ruminais foram utilizados com o objetivo de se estudar os efeitos da ingestão de níveis de fósforo sobre as características do metabolismo ruminal e digestão das rações. Foram avaliados os seguintes parâmetros: pH; concentração de amônia; volume e taxa de passagem do líquido ruminal; quantificação de minerais no conteúdo ruminal; digestibilidade com marcador (Cr2O3) e estimativa de excreção fecal de minerais. Os animais foram delineados em Quadrado Latino (4x4), com ingestão de quatro diferentes níveis de fósforo na dieta (8, 12, 15 e 18 gramas), mantendo-se a relação volumoso:concentrado foi de 85:15 e com o uso de cana de açúcar como único volumoso. Cada sub-período compreendeu 28 dias, sendo 14 de adaptação. Não houve influencia no pH,n a concentração de amônia, no volume e na taxa de passagem do líquido ruminal; nas concentrações de minerais no conteúdo ruminal (P, Ca, Mg, Na, K, S, Fe, Cu, Zn e Mn) e nos coeficientes de digestibilidade da matéria seca, fibra em detergente neutro, proteína bruta e energia bruta. Observou-se excreção linear de fósforo nas fezes em função ao fósforo ingerido da dieta, podendo ser estimada pela equação de regressão Y = 0,03 + 0,610 * X, onde Y é a quantidade de fósforo excretado nas fezes diariamente em g/kg0,75 e X é a quantidade de fósforo ingerido diariamente em g/kg0,75. / Four mature buffaloes fitted with rumen cannulas were used to study the effects of different levels of the phosphorus intake on the ruminal metabolism and the digestion in the diets. Ammonia concentration, pH, fluid and solid outflow rates, rumen volume; concentration of mineral in the ruminal content; digestibility and estimate of faecal output of minerals were determined. The animals were designed in Latin Square experiment (4x4) with each period of 28 d of duration. Treatments were applied four rations with different levels of P intake (8, 12, 15 e 18 grams). The proportion forage for concentrate was 85:15 with only using fresh chopped sugar cane. No differences were observed among the treatments in the rumen parameters evaluated and digestibility. Increasing in phosphorus intake resulted in simple linear regression equation Y = 0.03 + 0.610 * X, where P output daily (g (kg bodyweight)-0,75) was used as the dependent variable (Y) and P intake daily (g / kg-0,75) was used as the independent variable (X).
162

The Influence of Nitrogen and Phosphorus Supplements on the Composition of the Ruminal Ingesta of Sheep Grazing Desert Range Forage

Morris, James G. 01 May 1961 (has links)
Approximately 46 million acres or 88 per cent of the land area of the state of Utah has been classified by Reuss and Blanch (1951) as "range land open for grazing." Although some of this area cannot be grazed because of inaccessibility, lack of water, poison plants, and similar factors, it is estimated that some 40 million acres or 78 per cent of the total land area is available for grazing. Most of this grazing land is federally owned (73 per cent), while only 22 per cent is privately held, and 5 per cent is state owned.
163

Improvement of Nutrient Utilization Efficiency, Ruminal Fermentation and Lactational Performance of Dairy Cows by Feeding Birdsfoot Trefoil

Christensen, Rachael G. 01 May 2015 (has links)
Forages containing condensed tannins (CT) have potential to reduce the environmental impact of dairy farming. In 3 studies, I hypothesized that feeding CTcontaining birdsfoot trefoil (Lotus corniculatus, BFT) would result in improved nutrient utilization and lactational performance of dairy cows compared with control forages of the respective experiments. Improved milk components, reduction in waste N, and overall improved N efficiency were hypothesized for BFT-fed cows compared to those cows fed alfalfa hay (Study 1) or grass-based diets (Study 2). In addition, a decrease in in vitro methane production and improved rumen fermentation due to diets based on BFT pasture and concentrate supplementation compared with grass pasture-based diets was the hypothesis of the third study. Study 1 showed BFT-hay diets improved lactational performance through increased energy-corrected milk yield and increased milk protein yield, resulting in improved N utilization efficiency compared with the alfalfa hay diet. Total volatile fatty acids concentration tended to increase, and greater microbial protein yield was exhibited by cows fed BFT compared to other diets tested. Therefore, BFT can replace alfalfa hay in dairy diets and showed improved feed and N utilization efficiencies and lactational performance. Study 2 determined that pasture nutrient content increased for BFT pasture compared to the mixed grass control, contributing to increases in milk yield most weeks during the 2-year study. Energy-corrected milk yield increased most weeks by BFT-grazed cows due to increased milk yield, although milk protein concentration was similar between treatments. Cows grazing BFT pasture increased N efficiency coupled with decreased milk urea N secretion in the first, but not the second year, suggesting an environmental advantage over traditional grass-based pastures depending on the effect of growing conditions on pasture quality at time of grazing. Study 3 showed that offering BFT pasture to continuous cultures without or with barley grain or total mixed ration supplements reduced methane production and altered rumen microbial populations. The reduced methane production on the continuous cultures was likely due to direct and/or indirect effects of CT on rumen microbiota. Overall, diets including BFT showed improved nutritive, lactational, and environmental benefits by decreasing N waste and methane production over typical alfalfa hay-based dairy diets and grass pastures.
164

Assessment of Ruminal Fermentation Characteristics of Condensed Tannin-Containing Forages Using Continuous Cultures

Williams, Christina Marie 01 December 2010 (has links)
Two independent studies were conducted to assess the effects of feeding condensed tannin (CT)-containing forages to continuous cultures to evaluate their impacts on ruminal fermentation and digestibility, with an emphasis on methane (CH4) and ammonia-N (NH3-N) production. In Chapter 3, treatments consisted of: 1) 100% alfalfa hay (AH), 2) 50% AH and 50% birdsfoot trefoil hay (dry matter (DM) basis; AHBFTH), and 3) 100% birdsfoot trefoil hay (BFTH). Three replicated runs lasted 8 d each, with the first 5 d allowed for microbial adaptation to the diets, and 3 d for data collection and sampling. Methane, neutral detergent fiber (NDF) degradability, and total volatile fatty acid (VFA) production and profiles were not affected by the dietary treatments. However, NH3-N concentration and flow were reduced when replacing the AH with the BFTH. It was concluded that feeding a CT-containing diet (BFTH) increased the in vitro N utilization. In Chapter 4, five total mixed ration (TMR) diets were evaluated, each containing a different forage source as hay: 1) alfalfa (AHT), 2) cicer milkvetch (CMVHT), 3) Norcen birdsfoot trefoil (NBFTHT), 4) Oberhaunstadter birdsfoot trefoil (OBFTHT), and 5) sainfoin (SFHT). Total VFA production and acetate molar proportion were not influenced by treatments. However, molar proportion of propionate increased by the CMVHT, and decreased by the SFHT. Acetate to propionate ratio decreased with the CMVHT and the OBFTHT, but increased with the SFHT when compared to the AHT. Digestibilities of DM and NDF were not influenced by dietary treatments. Total CH4 production decreased by all treatments when compared to the AHT, whereas CH4 production expressed as mM per g of NDF digested was reduced only by the CMVHT and the OBFTHT. Ammonia-N concentration decreased when feeding the CMVHT and the SFHT. Feeding the CMVHT decreased ruminal concentration of C18:0, while ruminal C18:1 cis and trans isomers were greatest with the CMVHT. Because these effective tannin-free and tanniniferous legumes did not have negative impacts on ruminal fermentation, they can maintain potential productive performance of lactating dairy cows when fed as main forage sources in TMR diets.
165

Characterization of anthocyanidin-accumulating Lc-alfalfa for ruminants: nutritional profiles, digestibility, availability and molecular structures, and bloat characteristics

Jonker, Arjan 07 June 2011
Grazing cattle on alfalfa (Medicago sativa L.) would be economically beneficial, but its rapid initial rate of protein degradation results in pasture bloat, low efficiency of protein utilization and excessive N pollution into the environment. Introducing a gene that stimulates the accumulation of mono/polymeric anthocyanidins might reduce the ruminal protein degradation rate and reduce bloat related foam stability. The overall objective of this thesis was to evaluate newly developed anthocyanidin-accumulating Lc-alfalfa progeny for nutritional properties (composition, site of degradation and molecular structure), environmental emissions and bloat characteristics. The objective of the first study was to determine survival and phytochemical and chemical profiles of Lc-alfalfa progeny (BeavLc1, RambLc3 and RangLc4) and their non-transgenic (NT) parental cultivars (Beaver, Rambler and Rangelander). Lc-alfalfa forage accumulated enhanced amounts of anthocyanidin, with an average concentration of 197.4 µg/g DM, while proanthocyanidin (i.e. condensed tannins) were not detected. Both of these metabolites were absent in the NT-parental varieties. Lc-alfalfa progeny had ~3 % less crude protein (CP) and ~3 % more carbohydrates (CHO), which resulted in their 11 g/kg lower N:CHO ratio compared with NT-alfalfa. Total rumen-degradable N:CHO ratio based on chemical analysis was 12.9 g/kg lower in Lc-alfalfa compared with NT-alfalfa. The objective of the second study was to evaluate in vitro degradation, fermentation and microbial-N partitioning of three forage color phenotypes [green, light purple-green (LPG) and purple-green (PG)] within Lc-progeny and their parental green NT-alfalfa varieties. Purple-green-Lc alfalfa accumulated more anthocyanidin than Green-Lc with LPG-Lc intermediate. Gas, methane and ammonia accumulation rates were slower for the two purple-Lc phenotypes compared with NT-alfalfa with Green-Lc intermediate. Effective degradable DM and N were lower in the three Lc-phenotypes compared with NT-alfalfa. Anthocyanidin concentration correlated negatively with gas and methane production rates and effective degradability of DM and N. The objectives of the third study were to evaluate in situ ruminal degradation characteristics and synchronization ratios, and to model protein availability to dairy cattle and net energy for lactation of three Lc-alfalfa progenies, BeavLc1, RambLc3 and RangLc4 and the cultivar AC Grazeland (selected for a low initial rate of ruminal degradation). Anthocyanidin accumulation was on average 163.4 ìg/g DM in the three Lc-progeny while AC Grazeland did not accumulate anthocyanidin. The basic chemical composition of the original samples, soluble and potentially degradable fractions and degradation characteristics of crude protein and carbohydrates were similar in Lc-alfalfa and AC Grazeland. The undegradable in situ crude protein and neutral detergent fiber fraction were, respectively, 1.3 %CP and 4.8 %CHO lower in the three Lc-progeny compared with AC Grazeland. Lc-alfalfa had a 0.34 MJ/kg DM higher net energy for lactation and tended to have a 11.9, 6.9 and 8.4 g/kg DM higher rumen degradable protein, rumen degraded protein balance and intestinal available protein, respectively, compared with AC Grazeland,. The hourly rumen degraded protein balance included an initial and substantial peak (over-supply) of protein relative to energy which was highest in RangLc4 and lowest in RambLc3. The hourly rumen degraded protein balance between 4 and 24 h was similar and more balanced for all four alfalfa populations. The objective of the fourth study was to determine foam formation and stability in vitro from aqueous leaf extracts of three Lc-alfalfa progeny (BeavLc1, RambLc3, RangLc4), parental NT-alfalfa and AC Grazeland (bloat reduced cultivar) harvested in the field at 07:00 or 18:00 h. Anthocyanidin accumulation averaged 247.5 ìg/g DM in the leaves of the three Lc-progeny. There was an interaction between population and harvest time for the foam parameters. Initial foam volume (0 min) and final foam volume (150 min) at 07:00 h were lower for AC Grazeland compared with all other treatments and lower for RangLc4 compared with the other two Lc-progeny at 0 min and NT-alfalfa at 150 min; while from the 18:00 h harvest, initial foam volume was larger for NT-alfalfa and final foam volume was larger for RambLc3 compared with AC Grazeland, BeavLc1 and RangLc4. Foam formation correlated positively (R = 0.30 to 0.44) with leaf DM content, leaf extract protein and ethanol-film content, spectroscopic vibration intensity due to all carbohydrates (CHOVI) and amide I:amide II ratio and negatively (R = -0.33 and -0.34; P<0.05) with á-helix:â-sheet ratio and amide I:CHOVI. Final foam volume correlated negatively (R = -0.53 to -0.25; P<0.05) with leaf extract pH, spectroscopic vibration intensity due to all protein structures, structural carbohydrates (SCVI) and lipids (CH2 and CH3 asymmetric stretching) and amide I:CHOVI ratio and corelated positively (R = 0.39 to 0.44; P<0.05) with CHOVI, amideI:SCVI ratio and CHOVI:SCVI ratio. In conclusion, all Lc-alfalfa progeny and phenotypes accumulated anthocyanidin in their forage. Lc-alfalfa progeny had lower protein and higher carbohydrate content which improved the nitrogen to carbohydrate balance compared to their parental NT-alfalfa cultivars. Rate of fermentation and effective degradability in vitro reduced for both purple anthocyanidin-accumulating Lc-alfalfa phenotypes compared with NT-alfalfa. Intestinal protein availability tended to be higher and net energy for lactation was higher from Lc-alfalfa progeny for dairy cattle compared with AC Grazeland. Foaming properties were reduced in Lc-alfalfa progeny compared with parental non-transgenic alfalfa but not compared with AC Grazeland. However, differences between the Lc-alfalfa progeny and other cultivars were small. Therefore, further increases in mono/polymeric anthocyanidin accumulation in alfalfa are required in order to develop an alfalfa cultivar with superior nutritional and bloat preventing characteristics compared to currently available alfalfa cultivars.
166

Characterization of anthocyanidin-accumulating Lc-alfalfa for ruminants: nutritional profiles, digestibility, availability and molecular structures, and bloat characteristics

Jonker, Arjan 07 June 2011 (has links)
Grazing cattle on alfalfa (Medicago sativa L.) would be economically beneficial, but its rapid initial rate of protein degradation results in pasture bloat, low efficiency of protein utilization and excessive N pollution into the environment. Introducing a gene that stimulates the accumulation of mono/polymeric anthocyanidins might reduce the ruminal protein degradation rate and reduce bloat related foam stability. The overall objective of this thesis was to evaluate newly developed anthocyanidin-accumulating Lc-alfalfa progeny for nutritional properties (composition, site of degradation and molecular structure), environmental emissions and bloat characteristics. The objective of the first study was to determine survival and phytochemical and chemical profiles of Lc-alfalfa progeny (BeavLc1, RambLc3 and RangLc4) and their non-transgenic (NT) parental cultivars (Beaver, Rambler and Rangelander). Lc-alfalfa forage accumulated enhanced amounts of anthocyanidin, with an average concentration of 197.4 µg/g DM, while proanthocyanidin (i.e. condensed tannins) were not detected. Both of these metabolites were absent in the NT-parental varieties. Lc-alfalfa progeny had ~3 % less crude protein (CP) and ~3 % more carbohydrates (CHO), which resulted in their 11 g/kg lower N:CHO ratio compared with NT-alfalfa. Total rumen-degradable N:CHO ratio based on chemical analysis was 12.9 g/kg lower in Lc-alfalfa compared with NT-alfalfa. The objective of the second study was to evaluate in vitro degradation, fermentation and microbial-N partitioning of three forage color phenotypes [green, light purple-green (LPG) and purple-green (PG)] within Lc-progeny and their parental green NT-alfalfa varieties. Purple-green-Lc alfalfa accumulated more anthocyanidin than Green-Lc with LPG-Lc intermediate. Gas, methane and ammonia accumulation rates were slower for the two purple-Lc phenotypes compared with NT-alfalfa with Green-Lc intermediate. Effective degradable DM and N were lower in the three Lc-phenotypes compared with NT-alfalfa. Anthocyanidin concentration correlated negatively with gas and methane production rates and effective degradability of DM and N. The objectives of the third study were to evaluate in situ ruminal degradation characteristics and synchronization ratios, and to model protein availability to dairy cattle and net energy for lactation of three Lc-alfalfa progenies, BeavLc1, RambLc3 and RangLc4 and the cultivar AC Grazeland (selected for a low initial rate of ruminal degradation). Anthocyanidin accumulation was on average 163.4 ìg/g DM in the three Lc-progeny while AC Grazeland did not accumulate anthocyanidin. The basic chemical composition of the original samples, soluble and potentially degradable fractions and degradation characteristics of crude protein and carbohydrates were similar in Lc-alfalfa and AC Grazeland. The undegradable in situ crude protein and neutral detergent fiber fraction were, respectively, 1.3 %CP and 4.8 %CHO lower in the three Lc-progeny compared with AC Grazeland. Lc-alfalfa had a 0.34 MJ/kg DM higher net energy for lactation and tended to have a 11.9, 6.9 and 8.4 g/kg DM higher rumen degradable protein, rumen degraded protein balance and intestinal available protein, respectively, compared with AC Grazeland,. The hourly rumen degraded protein balance included an initial and substantial peak (over-supply) of protein relative to energy which was highest in RangLc4 and lowest in RambLc3. The hourly rumen degraded protein balance between 4 and 24 h was similar and more balanced for all four alfalfa populations. The objective of the fourth study was to determine foam formation and stability in vitro from aqueous leaf extracts of three Lc-alfalfa progeny (BeavLc1, RambLc3, RangLc4), parental NT-alfalfa and AC Grazeland (bloat reduced cultivar) harvested in the field at 07:00 or 18:00 h. Anthocyanidin accumulation averaged 247.5 ìg/g DM in the leaves of the three Lc-progeny. There was an interaction between population and harvest time for the foam parameters. Initial foam volume (0 min) and final foam volume (150 min) at 07:00 h were lower for AC Grazeland compared with all other treatments and lower for RangLc4 compared with the other two Lc-progeny at 0 min and NT-alfalfa at 150 min; while from the 18:00 h harvest, initial foam volume was larger for NT-alfalfa and final foam volume was larger for RambLc3 compared with AC Grazeland, BeavLc1 and RangLc4. Foam formation correlated positively (R = 0.30 to 0.44) with leaf DM content, leaf extract protein and ethanol-film content, spectroscopic vibration intensity due to all carbohydrates (CHOVI) and amide I:amide II ratio and negatively (R = -0.33 and -0.34; P<0.05) with á-helix:â-sheet ratio and amide I:CHOVI. Final foam volume correlated negatively (R = -0.53 to -0.25; P<0.05) with leaf extract pH, spectroscopic vibration intensity due to all protein structures, structural carbohydrates (SCVI) and lipids (CH2 and CH3 asymmetric stretching) and amide I:CHOVI ratio and corelated positively (R = 0.39 to 0.44; P<0.05) with CHOVI, amideI:SCVI ratio and CHOVI:SCVI ratio. In conclusion, all Lc-alfalfa progeny and phenotypes accumulated anthocyanidin in their forage. Lc-alfalfa progeny had lower protein and higher carbohydrate content which improved the nitrogen to carbohydrate balance compared to their parental NT-alfalfa cultivars. Rate of fermentation and effective degradability in vitro reduced for both purple anthocyanidin-accumulating Lc-alfalfa phenotypes compared with NT-alfalfa. Intestinal protein availability tended to be higher and net energy for lactation was higher from Lc-alfalfa progeny for dairy cattle compared with AC Grazeland. Foaming properties were reduced in Lc-alfalfa progeny compared with parental non-transgenic alfalfa but not compared with AC Grazeland. However, differences between the Lc-alfalfa progeny and other cultivars were small. Therefore, further increases in mono/polymeric anthocyanidin accumulation in alfalfa are required in order to develop an alfalfa cultivar with superior nutritional and bloat preventing characteristics compared to currently available alfalfa cultivars.
167

ALGAE OR YEAST SUPPLEMENTATION FOR LACTATING DAIRY COWS

Weatherly, Maegan E 01 January 2015 (has links)
The objective of the first study was to quantify the effects of feeding Schizochytrium sp. microalgae (SP-1, Alltech, Inc., Nicholasville, KY) on milk fat and DHA content. Eight cows were fed: 0, 100, 300, or 600 g of algae per day. Fat percentage was greater (P < 0.05) for cows on treatments 0 g and 100 g than for cows on treatments 300 g and 600 g (P < 0.05). Docosahexaenoic acid in milk was greater for cows on treatment 300 and 600 than for cows on treatment 0 and 100 (P < 0.05). The objective of the second study was to assess yeast supplementation effects on high and low forage dairy cow diets. Four cows were assigned to 1 of 4 treatments: 1) low forage (LF), 2) low forage with 10 g/d yeast (Yea-Sacc®; Alltech Inc., Nicholasville, KY; LFY), 3) high forage (HF), or 4) high forage with 10 g/d yeast (HFY). Only rumination time and DMI were influenced by treatment (P < 0.01). Dry matter intake was 17.05, 13.41, 19.44, and 20.29 ± 1.40 kg/d and rumination time was 442.88, 323.09, 433.34, and 475.50 ± 21.93 min/d for cows on the LF, LFY, HF, and HFY treatments, respectively.
168

Cinética ruminal de ovinos alimentados com bagaço do pseudofruto do caju desidratado em substituição a silagem de sorgo / Ruminal kinetic of sheep fed with bagasse pseudofruit cashew dehydrated substitution sorghum silage

Lopes, Kátia Tatiana de Lima 27 February 2014 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-16T13:14:31Z No. of bitstreams: 1 KátiaTLL_DISSERT.pdf: 805960 bytes, checksum: 7a77076eaccd692a619d926c4395a939 (MD5) / Made available in DSpace on 2017-03-16T13:14:32Z (GMT). No. of bitstreams: 1 KátiaTLL_DISSERT.pdf: 805960 bytes, checksum: 7a77076eaccd692a619d926c4395a939 (MD5) Previous issue date: 2014-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective was to evaluate the ruminal degradability of dry matter, and physicochemical parameters of the rumen fluid of sheep fed with bagasse pseudofruit cashew dehydrated replacing sorghum silage. Were used four crossbred sheep of Santa Inês x Morada Nova, fistulated in the rumen with na average weight of 30 ± 0.5 kg. Experimental tests were composed of four treatments, representing increasing levels of substitution of (BPCD) in sorghum silage, consisting of the levels of 0%, 8%, 16% and 24%, based on natural matter. We evaluated the potential degradability (PD) and effective (ED) of dry matter and the physical and chemical characteristics of rumen fluid (pH, temperature, ammonia nitrogen, methylene blue reduction time, flotation and sedimentation time, color, smell and consistency). The experimental design was a Latin square 4x4, with four substitution levels and four collection periods of rumen fluid after feeding, and the data submitted to analysis of variance and regression testing. The pH did not differ between treatments (P> 0.05). The temperature there was no significant difference (P> 0.05) on the basis of replacement levels of assessed BPCD, however, differed in terms of collection times. The ammonia nitrogen (NH3-N) presented significant difference (P <0.05); (P <0.01) according to the replacement levels BPCD and the rumen fluid sampling times after feeding. The methylene blue reduction time and flotation and sedimentation time significant differences (P <0.05); (P <0.01). The physical characteristics of rumen fluid were within the normal patterns. The potential degradability of dry matter with the addition of 24% of the cashew bagasse, has obtained value near of sorghum silage with 0% of cashew bagasse. The effective degradability of dry matter increased with the addition of BPCD, reaching higher values in the level of 24%. Results showed that the substitution of bagasse pseudofruit cashew dehydrated in sorghum silage did not affect the rumen environment, with potential degradability of dry matter silage next to the pure and higher effective degradability and can be used in up to 24% in diets for sheep / Objetivou-se avaliar a degradabilidade da matéria seca e as características físicoquímicas do ambiente ruminal de ovinos alimentados com bagaço do pseudofruto do caju desidratado em substituição a silagem de sorgo. Foram utilizados quatro ovinos mestiços de Santa Inês x Morada Nova fistulados no rúmen, com peso médio de 30 ± 0,5 kg. Os ensaios experimentais foram compostos por quatro níveis de substituição do bagaço do pseudofruto do caju desidratado (BPCD) na silagem do sorgo, constituído pelos níveis de 0%, 8%, 16% e 24%, com base na matéria natural. Foram avaliados a degradabilidade potencial (DP) e efetiva (DE) da matéria seca e as características físico-químicas do líquido ruminal (pH, temperatura, nitrogênio amoniacal, tempo de redução do azul de metileno, tempo de sedimentação e flotação, cor, odor e consistência). O delineamento experimental utilizado foi o quadrado latino 4x4, com quatro níveis de substituição do BPCD e quatro períodos de coleta do líquido ruminal após a alimentação, sendo os dados submetidos à análise de variância e teste de regressão. O pH não apresentou diferença entre os níveis de substituição (P>0,05). A temperatura não houve diferença significativa (P>0,05) em função dos níveis de substituição do BPCD avaliados, no entanto, diferiu em função dos tempos de coleta. O nitrogênio amoniacal (N-NH3) apresentou diferença significativa (P<0,05); (P<0,01) em função dos níveis de substituição do BPCD e dos tempos de coletas do líquido ruminal após a alimentação. O tempo de redução do azul de metileno e o tempo de sedimentação e flotação apresentaram diferenças significativas (P<0,05); (P<0,01). As características físicas do líquido ruminal se mostraram dentro dos padrões normais. A degradabilidade potencial da matéria seca com a substituição de 24% do bagaço de caju desidratado, obteve valor próximo ao da silagem de sorgo com 0% de bagaço de caju. A degradabilidade efetiva da matéria seca aumentou com o acréscimo do BPCD, atingindo valores superiores no nível de 24%. Os resultados demostraram que a substituição do bagaço do pseudofruto de caju desidratado na silagem de sorgo não comprometeu o ambiente ruminal, apresentando degradabilidade potencial da matéria seca próxima à da silagem de sorgo pura e degradabilidade efetiva superior, podendo ser utilizado em até 24% em dietas para ovinos / 2017-03-14
169

?leos essenciais na dieta de vacas em lacta??o / Essential oils in the diet of dairy cows

Oliveira, Hudson Bernardes Nunes January 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T12:08:09Z No. of bitstreams: 2 hudson_bernardes_nunes_oliveira.pdf: 547878 bytes, checksum: 66378b8548d84c2a55ae2734b5c7395b (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T12:08:35Z (GMT) No. of bitstreams: 2 hudson_bernardes_nunes_oliveira.pdf: 547878 bytes, checksum: 66378b8548d84c2a55ae2734b5c7395b (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T12:09:00Z (GMT) No. of bitstreams: 2 hudson_bernardes_nunes_oliveira.pdf: 547878 bytes, checksum: 66378b8548d84c2a55ae2734b5c7395b (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-01-05T12:09:00Z (GMT). No. of bitstreams: 2 hudson_bernardes_nunes_oliveira.pdf: 547878 bytes, checksum: 66378b8548d84c2a55ae2734b5c7395b (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Objetivou-se avaliar os efeitos de uma mistura comercial de ?leos essenciais (capsaicina, eugenol, cinamalde?do e carvacrol) microencapsulados, com inclus?es crescentes sobre o consumo, digestibilidade, desempenho e a composi??o do leite de 20 vacas Holandesas prim?paras. O delineamento adotado foi inteiramente casualizado, com parcelas subdivididas no tempo em esquema 4 ? 3 ? 5. A dieta experimental foi formulada para atender ?s exig?ncias dos animais e as doses de ?leos essenciais testadas foram de 0; 1,5; 3,0 e 4,5 gramas por animal ao dia. O experimento teve dura??o de 60 dias e foi divido em tr?s per?odos de 20 dias cada, com as coletas de alimentos, sobras, fezes e leite realizadas nos ?ltimos tr?s dias para posterior an?lise e c?lculos. A an?lise de vari?ncia foi realizada para todas as vari?veis usando modelo linear e, quando os efeitos foram significativos (P<0,05), o teste t-Student foi aplicado para discriminar as m?dias de quadrados m?nimos e quando n?o significativos, foi realizada uma an?lise descritiva. As correla??es existentes entre as medidas tomadas no mesmo animal e a produ??o antes do in?cio do experimento foi usada como covari?vel para verificar se a produ??o pr?via influenciou o resultado. N?o houve intera??o entre os tratamentos e os per?odos avaliados e o efeito dos tratamentos n?o foi significativo (P>0,05) para as vari?veis consumo, digestibilidade, desempenho e composi??o do leite. Mas, avaliando separadamente os per?odos testados, encontrou-se diminui??o significativa (P<0,05) na produ??o de leite e aumento nas concentra??es de s?lidos totais (ST). N?o houve diferen?a (P>0,05) para os teores de extrato seco desengordurado e contagem de c?lulas som?ticas. Concluiu-se que o composto de ?leos essenciais n?o teve intera??o com os per?odos estudados e os n?veis usados n?o influenciaram as vari?veis consumo, digestibilidade, produ??o e composi??o do leite de vacas holandesas prim?paras, indicando a necessidade de maiores estudos sobre o assunto. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Aimed to evaluate the effects of a commercial mixture of essential oils (capsaicin, eugenol, cinnamaldehyde and carvacrol) microencapsulated with increasing inclusion on intake, digestibility, performance and milk composition of primiparous Holstein cows 20.The design was completely randomized split plot with a 4 ? 3 ? 5 layout. The experimental diet was formulated to meet the requirements of the animals and the doses of essential oils tested were 0, 1.5, 3.0 and 4.5 grams per animal per day. The experiment lasted 60 days and was divided into three periods of 20 days each, with the collection of food scraps, feces and milk made in the last three days for further analysis and calculations. Analysis of variance was performed for all variables using linear model and when effects were significant (P <0.05), Student's T test was used to discriminate the least square means and when not significant, a descriptive analysis was performed.The correlations between the measures taken in the same animal and production before the start of the experiment was used as a covariate to determine whether the prior production influenced the outcome.There was no interaction between treatment and observation periods and the effect of the treatments was not significant (P> 0.05) for the variable intake, digestibility, performance and milk composition. But, evaluating separately tested periods, showed a significant decrease (P <0.05) on milk production and increased concentrations of total solids (TS).There was no difference (P> 0.05) to the levels of total solids and somatic cell count.It was concluded that the compound of essential oils had no interaction with the periods studied and the levels used did not influence variables intake, digestibility, milk production and composition of primiparous Holstein cows, indicating the need for further studies on the subject.
170

Avaliação nutricional em bovinos Nelore alimentados com dietas contendo alta concentração de amido / Nutritional evaluation in Nellore cattle fed diets containing high starch concentration

Godoi, Letícia Artuzo 22 February 2017 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-06-05T16:53:29Z No. of bitstreams: 1 texto completo.pdf: 884709 bytes, checksum: 3eb9b55934cb5ff92eca0ba053891524 (MD5) / Made available in DSpace on 2017-06-05T16:53:29Z (GMT). No. of bitstreams: 1 texto completo.pdf: 884709 bytes, checksum: 3eb9b55934cb5ff92eca0ba053891524 (MD5) Previous issue date: 2017-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Objetivou-se avaliar a digestão ruminal e intestinal de amido e demais constituintes em bovinos alimentados com dietas contendo milho em diferentes granulometrias ou grão de sorgo moído; verificar o efeito do processamento do milho sobre o pH, concentrações de nitrogênio amoniacal ruminal (NAR) e ácidos graxos voláteis (AGV); e avaliar as perdas de amido nas fezes em bovinos. Foram utilizados cinco bovinos machos não castrados da raça Nelore, fistulados no rúmen e no íleo, com peso médio inicial de 348±39,3 kg e idade média de 20±1 meses, distribuídos em delineamento experimental quadrado latino 5×5, sendo cinco dietas e cinco períodos. As dietas experimentais foram: 85% de grão de milho inteiro e 15% de pellet (MI); as demais foram compostas de 30% de silagem de milho, 10% de proteínado e 60% de milho quebrado (MQ); ou moído grosso (MG); ou moído fino (MF) ou sorgo moído fino (SF). Cada período teve duração de 21 dias, sendo 15 para adaptação e 6 dias de coleta. Do 16o ao 18o dia foi realizada coleta total de fezes e mensurado o pH ruminal, utilizando- se um bolus inserido no rúmen do animal, via fístula. Do 19o ao 21o dia foram realizadas oito coletas de digesta ruminal, omasal, ileal e fezes spot com intervalo de 9 horas, sendo o pH imediatamente mensurado. Os fluxos de matéria seca (MS) e dos constituintes das digestas omasal e ileal foram estimados utilizando o sistema de indicador duplo, sendo utilizados a fibra insolúvel em detergente neutro indigestível (FDNi) como indicador da fase sólida e o Co-EDTA para fase líquida e de pequenas partículas. Os dados foram analisados utilizando o procedimento MIXED do SAS. Todas as médias foram comparadas utilizando-se o teste Fisher, considerando 5% como nível crítico de probabilidade. Para os dados de pH ruminal, realizou-se a média pelo método de quadrados mínimos por intermédio do procedimento MIXED do SAS, estimando a área abrangida, obtendo-se o tempo e intensidade em que o pH ruminal situou-se abaixo do patamar mínimo requerido para a atividade adequada dos microrganismos ruminais. Os consumos (kg/dia) de MS, matéria orgânica (MO), fibra insolúvel em detergente neutro (FDNcp) e amido foram menores (P<0,05) para a dieta de MI e não diferiram (P>0,05) entre as demais. O consumo de proteína bruta (kg/dia) foi menor (P<0,05) para a dieta MI e maior para as dietas de MF e SF em relação às dietas de MQ e MG. As quantidades degradadas (kg/dia) no rúmen de MS foram menores (P<0,05) para a dieta de MI em relação às dietas contendo milho e sorgo moídos fino e aumentaram quantitativamente à medida que os grãos de milho foram mais processados. Quanto a MO, foram menores (P<0,05) para a dieta do MI, que não diferiu da dieta do MQ, também não houve diferença (P>0,05) entre as dietas em que o milho ou sorgo foram processados. Para o amido, não houve efeito do processamento (P>0,05) e para FDNcp foi menor (P<0,05) para a dieta MI e não diferiu (P>0,05) entre as demais. A digestibilidade aparente total (kg/dia) da MS, MO, amido e FDNcp foi menor (P < 0,05) para a dieta MI e não diferiu entre as demais formas de processamento. O valor médio de eficiência microbiana foi de 132,2 g de PBmic/kg de NDT. Não houve efeito (P>0,05) da granulometria sobre as concentrações de NAR (mg/dL) e AGV (mmol/dL), porém a granulometria alterou as proporções molares de AGV. A relação acetato:propionato foi reduzida, quando o milho é fornecido inteiro ou quando os cereais são mais intensamente processados, promovendo redução do pH ruminal, porém, não alterou significativamente o teor de amido fecal em relação aos demais processamentos. Conclui-se que a granulometria da dieta, exceto quando o milho é fornecido inteiro, não altera os consumos e a digestibilidade aparente total da maioria dos constituintes das dietas. A granulometria da dieta altera o pH ruminal, sendo menor à medida que ocorre maior processamento dos grãos. No entanto, granulometrias menores resultam em maiores digestões total e ruminal do amido e maior síntese de proteína bruta microbiana. / An experiment was developed aiming (1) to evaluate ruminal and intestinal digestion of starch and other nutrients in bulls fed diets containing corn in different grain sizes or finely ground sorghum; (2) to verify the effect of corn processing on pH, rumen ammonia nitrogen concentrations (RAN) and volatile fatty acids (VFA); (3) and to evaluate fecal starch losses of Nellore bulls. Five Nellore young bulls, fitted in the rumen and ileum, weighing, on average, 348±39.3 kg and age of 20±1 months were used. The animals were distributed in a 5×5 Latin square design, with five diets and five periods. The experimental diets were: 85% whole corn grain and 15% pellet (WC), while the other diets were composed of 30% corn silage, 10% protein supplement and 60% cracked corn (CC); or largely ground corn (CGC); or finely ground corn (FGC) or finely ground sorghum (FGS). Each period lasted 21 days, being 15 days for acclimation and 6 days for data collection. From the 16th to 18th days, total fecal collection was performed and ruminal pH was measured using a bolus inserted to ruminal fistula. From the 19th to 21th day, eight samples of ruminal, omasal, and ileal digesta were performed in a 9-h interval as well as spot samples of feces and the pH was immediately measured. The dry matter (DM) and digestible nutrients from omasal and ileal digesta were estimated using the double marker system, with indigestible neutral detergent fiber (iNDF) as solid phase marker and Co-EDTA for liquid phase and small particles. Data were analyzed using the MIXED procedure of SAS. Means were compared using Fisher test, considering 5% as the critical probability level. For the data of ruminal pH, the minimum square method was performed using the MIXED SAS procedure, estimating the area covered below the line represented by the time and intensity at which the ruminal pH was below the required minimum level for proper ruminal microorganism activity. The DM, organic matter (OM), neutral detergent fiber (NDF) and starch (kg/day) intake were lower (P<0.05) for the WC diet and they did not differ (P>0.05) among the others. The crude protein intake (kg/day) was lower (P<0.05) for the WC diet and greater for the FGC and FGS diets in relation to the BC and CGC diets. The DM degraded amount (kg/day) in the rumen was lower (P<0.05) for the WC diet in relation to diets containing corn and finely ground sorghum and it increased quantitatively as corn was processed. For OM, the degraded amount was lower (P<0.05) for WC diet, that it did not differ from the CC diet. Also, there was not difference (P>0.05) among diets which corn or sorghum were processed. For starch, there was not effect of corn processing (P>0.05) while for NDFap it was lower (P<0.05) for the WC diet and it did not differ (P>0.05) among other diets. Total apparent digestibility (kg/day) of DM, OM, starch, and NDFap was lower (P<0.05) for the WC diet and they did not differ among corn processing. The mean value of microbial efficiency was 132.2 g MCP/kg TDN. There was no effect (P>0.05) of the corn processing on the RAN (mg/dL) and VFA (mmol/dL) concentrations, but corn size altered molar VFA proportions. The acetate:propionate ratio was reduced when corn was provided as whole or when cereals were finely processed causing reduction on ruminal pH, which did not significantly alter the fecal starch content in the diets with more processed cereals. Therefore, we concluded that corn size, except for whole corn, does not alter intake and total apparent digestibility of the majority of the constituents of the diets. Also, corn processing changes ruminal pH, being smaller with greater corn processing. However, smaller grain size results in larger total and rumen starch digestion and greater microbial crude protein synthesis.

Page generated in 0.0652 seconds