Transactions of magnesium (Mg) along the gastrointestinal tract and the effect of change in potassium (K) intake were recorded in two in vivo experiments in sheep and cattle. Additional information on the sensitivity to K intake was obtained by comparing Mg transport and electrochemical properties of isolated rumen epithelia of sheep and cattle in 4 additional in vitro experiments. The experiment described in Chapter 2, and performed in sheep housed indoors in metabolic crates, investigated the compensatory capacity of the intestine to respond to the reduction in Mg absorption from the stomach as a consequence of increase in K intake. The animals were equipped with a ruminal cannula and two intestinal cannulae (duodenum and ileum) and flow of digesta was measured by the addition of two indigestible markers, chromium ethylenediaminetetra-acetic acid (Cr-EDTA) and ytterbium acetate (Yb). The animals were infused in a Latin square design for periods of 10 days with a solution of K bicarbonate that provided between 15 and 47 g of K/day. The diet consisted of a 50:50 combination of concentrates plus lucerne hay that provided around 3.7 g of Mg per day and 15 g of K per day. After 5 days of infusion samples of feed, faeces, urine and plasma were collected and analysed for Mg and K content. After 6 days of infusion, samples of duodenal and ileal flow were obtained. The treatments reproduced the detrimental effect of K on Mg absorption, especially in the rumen; a rise in K intake from 15 to 23 g/day reduced total Mg absorption from the gastrointestinal tract from 1.36 to 1.23 g/day, further increase in K intake to 38 and 47 g/day reduced absorption to 1.12 and 1.05 g/day, an overall reduction of around 50% in Mg apparent availability. Magnesium was mainly absorbed in the stomachs and large intestine with the small intestine a site of net secretion. Most of the reduction in Mg absorption with increase in K intake occurred in the stomachs, reducing from 1.86 to 1.11 g/day. A compensatory reduction in the net secretion of Mg from the intestines (small and large) was observed. This compensation was largely due to reduction in net secretion from the small intestine, from 0.85 to 0.22 g/day, rather than an increase in net absorption from the large intestine, although both segments acted synergistically. Results also suggested significant individual variation in plasma Mg concentration, urinary Mg excretion and in the flow and absorption of Mg along the gastrointestinal tract. It was suggested that most of that variability was due to genetic factors. Differences between species (cattle and sheep) were pursued during the course of the experiment described in Chapter three. Four triple cannulated rams and 3 triple cannulated dry cows were placed in metabolic crates, fed daily fresh-cut pasture and infused, in a total randomised design that provided the equivalent of an intake of 30,40 and 50 g of K per kg dry matter intake (DMI) per day. Solutions of K (as K bicarbonate) and markers (CrEDT A and Yb acetate) were infused continuously for a period of 10 days; after 5 days of infusion samples of pasture, faeces, urine and plasma were collected and analysed for Mg and K content. After 6 days of infusion, samples of duodenal and ileal flow were obtained. Total feed offered, refusals and water consumption were recorded daily. Results showed a greater sensitivity of cattle to the increase in K supply. A rise in K supply from 30 to 40 g per kg DMI/day reduced Mg absorption by almost 50% from 0.32 to 0.16 g per kg DMI/day, whereas only the highest treatment dose (50 g of K per kg DMI/day) produced the same deleterious effect in sheep. The absorption of Mg occurred mainly in the stomachs and large intestine; in contrast the small intestine was a site of net secretion in both species. The addition of K slightly reduced the rate of Mg absorption from the rumen, especially in cattle. Similarly, net Mg secretion within the intestines increased with increasing K intake in both species, only to be counterbalanced by a greater Mg absorption from the large intestine. The large intestine in both species (sheep and cattle) reduced faecal losses of Mg but was unable to fully compensate for the reduction in Mg absorption from the stomach or the greater net Mg secretion observed at the small intestine. Differences between species in water content of the faeces were observed to be mainly related to the moisture content of the digesta that reached the ileum rather than a result of differences in absorption in the large intestine. More evidence of species differences in Mg transport and of sensitivity to K intake were obtained by using isolated rumen epithelia and the Ussing chamber technique. Transport and electrophysiological properties of the tissues were observed in standard conditions and by adding different K concentrations to the mucosal side. Under standard conditions and open-circuit voltage, sheep isolated rumen epithelia had greater transmural potential difference (PDt), and lower conductance (Gt) but similar short-circuit current (Isc) than those from cattle. These results suggested that the rumen epithelium of cattle is leakier than that of sheep. Measurement of the transport of Mg showed that isolated rumen epithelia of cattle transported more Mg and was saturated at higher Mg concentrations (12 vs 4 mM) than sheep epithelia. These differences in Mg influx (transport from mucosa to serosa) were also observed in studies of Mg transport using stable isotopes. Magnesium influx (transport from mucosa to serosa) from the isolated rumen of cattle was greater than in sheep (57.5 ± 12.72 vs. 17.3 ± 12.72 nmol.cm⁻².h⁻¹); however this was counterbalanced by a greater Mg efflux (transport from serosa to mucosa) of 48.1 ± 12.72 vs. 9.9 ± 12.72 nmol.cm⁻².h⁻¹, for cattle and sheep respectively, when mucosal K concentrations were around 25 mM. A increase in K concentration on the mucosal side enhanced transmural potential difference (PDt) and short-circuit current (Isc) to a greater extent in sheep than in cattle, suggesting a greater effect of K on sheep than on cattle epithelia. On the other hand, the transport of Mg measured by stable isotopes suggested that net absorption of Mg (7.4 ± 12.72 vs. 11.1 ± 12.72 nmol.cm⁻².h⁻¹) in sheep epithelia was similar at 25 and 50 mM of K on the mucosal side, whereas net Mg influx in cattle was largely depressed as a consequence of a reduction in Mg influx (mucosa to serosa) from 57.7 ± 12.72 to 2.9 ± 12.72 nmol.cm⁻² h⁻¹ together with a constant Mg efflux (serosa to mucosa) 48.1 ± 12.72 and 41.2 ± 12.72 nmol.cm⁻².h⁻¹, presumably leaving through a paracellular shunt. However, this finding was based on date from a small size and caution should be applied to this conclusion. In conclusion, data collected from several comparative studies suggest differences in Mg apparent availability between sheep and cattle and also a greater sensitivity of cattle to an increase in K intake. This high sensitivity to K represents a great risk of hypomagnesaemia in dairy cattle in New Zealand where high K concentration is endemic in pastures. Most importantly, these results suggest that models for Mg metabolism in cattle should be based on measurements from cattle nutritional and physiological studies rather than on extrapolation from sheep studies.

Human milk contains ~ 25 µg/mL of soluble cluster of differentiation 14 (sCD14) protein, a pattern recognition receptor (PRR) that triggers the innate immune system to respond to bacterial lipopolysaccharide (LPS). To date, the role of CD14 in the digestive tract of breast fed infants has not been well characterized and is the subject of this thesis. To investigate the biodistribution of proteins such as CD14 in vivo, a novel method for 14C radiolabeling of proteins to high specific radioactivity was developed using in vacuo methylation. Bovine serum albumin (BSA) and casein were used as test proteins to determine the following: 1) The efficacy of the in vacuo radiolabeling procedure; 2) The extent of incorporation of the 14C-label into the organs of oro-gastric gavaged 10 day old Sprague Dawley rats. [14C]BSA, [14C]casein and [14C]CD14 were prepared with specific radioactivities of 10 400, 10 800 and 163 000 dpm/µg, respectively. After feeding 6.25 µg of 14C-labeled proteins, quantifiable levels of 14C were found in the stomach, jejunum, duodenum, ileum, large intestine, intestinal luminal flushes, blood, liver, spleen and kidneys of rats. The accumulation of radiolabel in the organs of [14C]CD14 fed rats was temporally and spatially distinct from [14C]BSA and [14C]casein. Most notably, the label persisted in the stomach 480 min post-gavage. To design a neonate animal model for biodistribution, the segmental and total gastrointestinal transit times (GItt) were measured in two litters of 10 and 15 day old Sprague Dawley rat pups using barium sulfate. Ten day old rat pups that remained with and without the dam had a total gastrointestinal transit time of 13.8 ± 0.9 hr and 9.3 ± 0.7 hr, respectively. This decrease (p<0.05) in total gastrointestinal transit time in the absence of the dam was age dependent, as it was not observed (p>0.05) in the 15 day old rat pup litter. The immunological impact of an exogenous sCD14 source was examined in human peripheral blood mononuclear cells (PBMC). Pre-treatment of CD14+ monocytes with sCD14 had a protective effect, one of reducing the production of proinflammatory cytokines (TNF-α, IL-6, IL-8, IL-1β) when challenged with LPS. 14C was absorbed by neonate rats upon ingestion of [14C]CD14 and exposure to relatively high concentrations of rCD14 led to a reduction in inflammation. This may be beneficial to initial gut colonization in breast-fed newborns. / Alexander Graham Bell NSERC CGS M scholarship. Japan Society for the Promotion of Sciences, Summer in Japan Fellowship. Funded by the Canadian Institutes of Health Research, Institute of Nutrition Metabolism and Diabetes Grant #82816 “Fate and function of breast milk and recombinant human CD14 at mammary and newborn gastrointestinal mucosal epithelia”.

Human milk contains ~ 25 µg/mL of soluble cluster of differentiation 14 (sCD14) protein, a pattern recognition receptor (PRR) that triggers the innate immune system to respond to bacterial lipopolysaccharide (LPS). To date, the role of CD14 in the digestive tract of breast fed infants has not been well characterized and is the subject of this thesis. To investigate the biodistribution of proteins such as CD14 in vivo, a novel method for 14C radiolabeling of proteins to high specific radioactivity was developed using in vacuo methylation. Bovine serum albumin (BSA) and casein were used as test proteins to determine the following: 1) The efficacy of the in vacuo radiolabeling procedure; 2) The extent of incorporation of the 14C-label into the organs of oro-gastric gavaged 10 day old Sprague Dawley rats. [14C]BSA, [14C]casein and [14C]CD14 were prepared with specific radioactivities of 10 400, 10 800 and 163 000 dpm/µg, respectively. After feeding 6.25 µg of 14C-labeled proteins, quantifiable levels of 14C were found in the stomach, jejunum, duodenum, ileum, large intestine, intestinal luminal flushes, blood, liver, spleen and kidneys of rats. The accumulation of radiolabel in the organs of [14C]CD14 fed rats was temporally and spatially distinct from [14C]BSA and [14C]casein. Most notably, the label persisted in the stomach 480 min post-gavage. To design a neonate animal model for biodistribution, the segmental and total gastrointestinal transit times (GItt) were measured in two litters of 10 and 15 day old Sprague Dawley rat pups using barium sulfate. Ten day old rat pups that remained with and without the dam had a total gastrointestinal transit time of 13.8 ± 0.9 hr and 9.3 ± 0.7 hr, respectively. This decrease (p<0.05) in total gastrointestinal transit time in the absence of the dam was age dependent, as it was not observed (p>0.05) in the 15 day old rat pup litter. The immunological impact of an exogenous sCD14 source was examined in human peripheral blood mononuclear cells (PBMC). Pre-treatment of CD14+ monocytes with sCD14 had a protective effect, one of reducing the production of proinflammatory cytokines (TNF-α, IL-6, IL-8, IL-1β) when challenged with LPS. 14C was absorbed by neonate rats upon ingestion of [14C]CD14 and exposure to relatively high concentrations of rCD14 led to a reduction in inflammation. This may be beneficial to initial gut colonization in breast-fed newborns. / Alexander Graham Bell NSERC CGS M scholarship. Japan Society for the Promotion of Sciences, Summer in Japan Fellowship. Funded by the Canadian Institutes of Health Research, Institute of Nutrition Metabolism and Diabetes Grant #82816 “Fate and function of breast milk and recombinant human CD14 at mammary and newborn gastrointestinal mucosal epithelia”.

The animal phylogeny and feeding habits would affect the composition of gastrointestinal tract¡]GI tract¡^microbiota. GI tract microbiota plays an important role in host health and nutrient provision. In this study, we used PCR-DGGE and bacterial 16S rDNA sequencing to analyze the GI tract bacterial diversity of four animals with different feeding habits in Shou-Shan zoo, including one carnivore, one omnivore and two herbivores, in which one ruminant and one non-ruminant. The results show a great difference between GI tract bacterial diversity of the four animals. The abundance of GI tract bacterial diversity increased from carnivore, omnivore to herbivore. Comparing the similarity of the GI tract bacterial community structures of these four animals, the carnivore possessed the most different composition, to other animals, the next was the omnivore, while the two herbivores show the highest similarity to each other. Our results also indicated that the GI tract microbiota of these four different animals were very stable during the investigating period. We also found that two individuals of the same species had a very similar bacterial compositions in their GI tracts at different time point. This finding indicated that the bacterial compositions of GI tract in the four animals were affected mostly by the host phylogeny and their feeding habits. Moreover, according to bacterial 16S rDNA sequencing and idencification, results show that the Firmicutes were the dominant bacterial phyum in all four animals GI tracts, the amount of Bacteroides was much less than Firmicutes. This result might caused by the highly starch content in their feed. Large amount of carbohydrate-degrading, protein-degrading, lipid-degrading bacteria were found in all of these different animals. Fiber-degrading bacteria Fibrobacteres were identified in the GI tracts of the herbivores and omnivore, but not the carnivore, showing that GI tract microbiota plays an important role to provide nutrient and assist energy to the host.

Human milk contains ~ 25 µg/mL of soluble cluster of differentiation 14 (sCD14) protein, a pattern recognition receptor (PRR) that triggers the innate immune system to respond to bacterial lipopolysaccharide (LPS). To date, the role of CD14 in the digestive tract of breast fed infants has not been well characterized and is the subject of this thesis. To investigate the biodistribution of proteins such as CD14 in vivo, a novel method for 14C radiolabeling of proteins to high specific radioactivity was developed using in vacuo methylation. Bovine serum albumin (BSA) and casein were used as test proteins to determine the following: 1) The efficacy of the in vacuo radiolabeling procedure; 2) The extent of incorporation of the 14C-label into the organs of oro-gastric gavaged 10 day old Sprague Dawley rats. [14C]BSA, [14C]casein and [14C]CD14 were prepared with specific radioactivities of 10 400, 10 800 and 163 000 dpm/µg, respectively. After feeding 6.25 µg of 14C-labeled proteins, quantifiable levels of 14C were found in the stomach, jejunum, duodenum, ileum, large intestine, intestinal luminal flushes, blood, liver, spleen and kidneys of rats. The accumulation of radiolabel in the organs of [14C]CD14 fed rats was temporally and spatially distinct from [14C]BSA and [14C]casein. Most notably, the label persisted in the stomach 480 min post-gavage. To design a neonate animal model for biodistribution, the segmental and total gastrointestinal transit times (GItt) were measured in two litters of 10 and 15 day old Sprague Dawley rat pups using barium sulfate. Ten day old rat pups that remained with and without the dam had a total gastrointestinal transit time of 13.8 ± 0.9 hr and 9.3 ± 0.7 hr, respectively. This decrease (p<0.05) in total gastrointestinal transit time in the absence of the dam was age dependent, as it was not observed (p>0.05) in the 15 day old rat pup litter. The immunological impact of an exogenous sCD14 source was examined in human peripheral blood mononuclear cells (PBMC). Pre-treatment of CD14+ monocytes with sCD14 had a protective effect, one of reducing the production of proinflammatory cytokines (TNF-α, IL-6, IL-8, IL-1β) when challenged with LPS. 14C was absorbed by neonate rats upon ingestion of [14C]CD14 and exposure to relatively high concentrations of rCD14 led to a reduction in inflammation. This may be beneficial to initial gut colonization in breast-fed newborns. / Alexander Graham Bell NSERC CGS M scholarship. Japan Society for the Promotion of Sciences, Summer in Japan Fellowship. Funded by the Canadian Institutes of Health Research, Institute of Nutrition Metabolism and Diabetes Grant #82816 “Fate and function of breast milk and recombinant human CD14 at mammary and newborn gastrointestinal mucosal epithelia”.

No description available.

No description available.

Thesis (Ph. D.)--University of New South Wales, 2004. / Title from PDF title page (viewed on Mar. 25, 2006). Includes bibliographical references (p. 264-286).

Ecotoxicity testing of chemicals for environmental risk assessment is an area where a high number of vertebrates are used across a variety of industrial sectors. The application of the 3Rs in toxicity testing using fish address both the ethical and societal concerns around this issue in addition to the increasing legislative requests for the incorporation of animal alternatives. This thesis aims to highlight the potential of 3D cell culture models to "bridge the gap" between in vitro and in vivo screening procedures for testing of chemicals with the potential to persist or bioaccumulate thereby improving the predictive power of screening procedures. This thesis examines two alternative methods for their potential use as an intestinal based toxicokinetic tool for environmental risk assessment, utilising an in vitro fish cell line replacement tool (RTgutGC). In addition, for the first time a new intestinal primary cell culture based model was developed to address both intestine region specific response (pyloric, anterior, mid and posterior) and size related adaptability to toxins. Paramagnetic oximetry was used to measure oxygen content within 3D structures (spheroids) in order to better understand the microenvironment of these culture models. Using histology, immunohistochemistry, transepithelial electrical resistance (TEER), transmission electron microscopy (TEM), metabolic, fluorescence and gene expression assays, the comparability of this system to native intestinal response was established. Following exposure to carefully chosen environmental contaminants (Benzo[a]pyrene and Copper), the RTgutGC cell line demonstrated comparable responses to existing literature in terms of uptake, metabolism, DNA damage and the presence an equivalent saturable level. Primary enterocytes cultured on transwell inserts remained viable for upto six weeks, with permeability and metabolic activity comparable to native tissue (both in vitro and ex vivo). Taken in combination, these features of enterocytes represent a profile more closely representative of the intestine then the widely used "gut sac" method. With the potential advantages of incorporating complexity at differing levels (connective tissue layer, intestinal bacteria biome), the intestinal models described offer the potential to screen highly persistent toxins which may require prolonged incubation, in addition to the exploration of complex experimental designs which minimise animal usage (uptake, depuration, uptake). As a consequence, the models developed within this thesis significantly enrich the emerging fish based in vitro testing strategies.

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Agradecemos a compreensão. on 2017-09-06T16:31:12Z (GMT) / Submitted by MARINA ELIZABETH BARBOSA ANDRADE null (marina.elizabeth.15@hotmail.com) on 2017-09-06T19:11:35Z No. of bitstreams: 1 Dissertacao_Marina_Elizabeth_Barbosa_Andrade.pdf: 1979789 bytes, checksum: e5046942b9fb3e5014e6fa1eadfcd9db (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-11T19:35:47Z (GMT) No. of bitstreams: 1 andrade_meb_me_jabo.pdf: 1979789 bytes, checksum: e5046942b9fb3e5014e6fa1eadfcd9db (MD5) / Made available in DSpace on 2017-09-11T19:35:47Z (GMT). No. of bitstreams: 1 andrade_meb_me_jabo.pdf: 1979789 bytes, checksum: e5046942b9fb3e5014e6fa1eadfcd9db (MD5) Previous issue date: 2017-07-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho foi realizado utilizando informações de 7 estudos, em que foram ajustadas curvas de crescimento ao desenvolvimento dos órgãos do sistema visceral de fêmeas, machos castrados e machos inteiros da raça Saanen de 0,5 a 19,5 meses de idade. Inicialmente, foram avaliados oito modelos: Regressão linear simples; Quadrático; Monomolecular; Brody; Von Bertalanffy; Logística; Gompertz; e Richards. Os dados dos órgãos viscerais (fígado, pâncreas, baço, rúmen-retículo, omaso, abomaso, intestino delgado e intestino grosso) e tecido adiposo mesentérico (TAM), foram ajustados nos modelos usando o procedimento NLMIXED do SAS. O melhor modelo ajustado foi escolhido com base no Critério de Informações Akaike corrigido para pequenas amostras (AICc) e nos coeficientes de correlação de concordância (CCC). Após a escolha do modelo que melhor ajustou a curva de crescimento dos órgãos viscerais avaliados, modelamos a variância buscando um melhor ajuste. Os parâmetros dos modelos para cada sexo foram comparados utilizando o comando CONTRAST (p < 0,10). Em geral, o modelo que melhor descreveu o crescimento de órgãos do sistema visceral foi o logístico (menor AICc e maior CCC). Quando os órgãos foram expressos em gramas, o sexo não influenciou os parâmetros das equações para predição do crescimento dos órgãos avaliados (p > 0,10), exceto o MAT (p < 0,02); em que as fêmeas apresentaram menor taxa de deposição comparada aos machos inteiros e castrados (0,318 ± 0,034 vs 0,659 ± 0,062), e um ponto de inflexão superior ao dos machos inteiros e castrados (7,7 vs 3,7 meses). No entanto, essa diferença entre os sexos não é encontrada quando o MAT é expresso em % ao peso do corpo vazio (PCV). Independentemente do sexo, no início do crescimento, o fígado representou 2,75 ± 0,113 % do PCV, cresceu (g) a uma taxa máxima de 0,531 ± 0,062, e o ponto de inflexão de sua curva ocorreu em 1,7 meses. O trato gastrointestinal (TGI) representou 9,14 ± 0,493 % PCV, e à medida que os animais cresceram o TGI diminuiu sua porcentagem em relação ao PCV a uma taxa constante de 0,135 ± 0,046 %. Considerando o período avaliado, em geral, o rúmen-retículo e o intestino grosso aumentaram sua porcentagem em relação ao PCV e TGI, enquanto o abomaso e o intestino delgado diminuíram sua porcentagem em relação ao PCV e TGI, à medida que o animal crescia. O rúmen-retículo e o intestino grosso, que estão diretamente relacionados à digestão de alimentos sólidos, apresentaram maiores taxas de crescimento nos dois primeiros meses de vida. Os resultados evidenciaram que o sexo não afeta o crescimento de órgãos do sistema visceral (g), exceto para MAT, porém, quando olhamos em % PCV alguns órgãos mostram diferenças entre os sexos, como o fígado, abomaso, intestino delgado, intestino grosso e intestinos. O conhecimento da curva de crescimento dos órgãos viscerais pode ser muito útil para melhorar a compreensão de seu impacto sobre as exigências nutricionais desses animais, e ser utilizado para otimizar ou desenvolver um plano nutricional adequado para cada fase de crescimento, como também auxiliar os produtores a desenvolver planos estratégicos em um rebanho de caprinos, como a melhor idade para desmame e abate desses animais. / This work was performed gathering information of 7 studies, in which growth curves were fitted to the visceral organs of female, intact male, and castrated male Saanen goats from 0.5 to 19.5 months old. Initially, eight models were assessed: Monomolecular; Simple linear regression; Quadratic; Monomolecular; Brody; Von Bertalanffy; Logistics; Gompertz; and Richards. Data of the visceral organs (liver, pancreas, spleen, rumen-reticulum, omasum, abomasum, small intestine, and large intestine) and mesenteric adipose tissue (MAT) were fitted in the models using NLMIXED procedure of SAS. The best fitted model was choosing based on the Akaike Corrected Information Criterion for small samples (AICc) and values and the concordance correlation coefficient (CCC). After choosing the model that best fitted the growth curve of the evaluated visceral organs, we modelled the variance seeking a better fit. Parameters of the models for each sex were compared using the CONTRAST statement (p < 0.10). Overall, the model that best described visceral organ growth was the logistic (i.e., lower AICc and higher CCC). When organs were expressed in grams, the sex did not influence the parameters of equations to predict the growth of the evaluated organs (p > 0.10), except for TAM (p < 0.02); females presented a lower deposition rate compared to intact males and castrated males (0.318 ± 0.034 vs 0.659 ± 0.062), and a inflection point higher than intact males and castrated males (7.65 vs 3.69 months). However, this difference between the sexes is not found when TAM is expressed in % to empty body weight (EBW). Irrespective of sex, at the beginning of growth, liver stood for 2.75 ± 0.113 % of EBW, grew (g) at a maximum rate of 0.531 ± 0.062, and its inflection point of the curve occurred at 1.7 months. The gastrointestinal tract (GIT) stood for 9.14 ± 0.493 % EBW, and as the goats grew the GIT decreased its percentage in relation to the EBW at a constant rate of 0.135 ± 0.046 %. Considering the evaluated period, in general rumen-reticulum and large intestine increased their percentage in relation to EBW and GIT, whereas abomasum and small intestine decreased their percentage in relation to EBW and GIT, as animal grew. The rumen-reticulum and large intestine, which are directly related to the digestion of solid foods, presented higher growth rates in the first two months of life. The results highlighted that sex does not affect the growth of visceral organs (g), except for TAM. However, when we look at % EBW, some organs show differences between the sexes, such as the liver, abomasum, small intestine, large intestine and Intestines. Knowledge of the growth curve of the visceral organs can be very useful in improving the understanding of their impact on the nutritional requirements of these animals and can be used to optimize or develop a nutritional plan suitable for each growth phase, but also to help producers develop strategic plans for a herd of goats, such as the best age for weaning and slaughtering these animals.