Histomorphometric changes of the fore-stomach of lambs fed with diets containing spineless cactus genotypes resistant to Dactylopius sp

Red propolis extract as a natural ionophore for confined sheep: performance and morphological and histopathological changes

This study aimed to evaluate the effect of increasing levels of red propolis extract (RPE) in the diet of confined sheep on performance and histomorphometric parameters of rumen and intestine and histopathological parameters of liver and kidney. Thirty-five male sheep (17.08 ± 2.36 kg) were used, distributed in a completely randomized design, with five treatments (0, 7, 14, 21, and 28 mL day-1 RPE) and seven replications, submitted to 68 days of experiment. At the end of the experimental period, the animals were euthanized, and samples of rumen, intestine, liver, and kidney were collected to histomorphometry and histopathology analyzes. Higher RPE inclusions (21 and 28 mL day-1) maintained dry matter intake and increased total weight (5.78 x 6.14 and 6.95 kg, respectively) gain up to 20.24%. In the rumen, the inclusion of RPE led to an increase in the thickness of the epithelium and the highest level also increased the thickness of the keratinized portion of this epithelium (21.71 x 32.15 μm). The level of 21 mL day-1 provided larger ruminal papillae (1620.68 x 1641.70 μm) and greater ruminal absorption area (561791.43 x 698288.50 μm2). In intestine 21 and 28 mL-1 of RPE provided greater mucosal thickness (468.54 x 556.20 and 534.64 μm), higher goblet cell index (23.32 x 25.82 and 25.64) and higher hepatic glycogen index (1.47 x 1.64 and 1.62), supporting higher nutrients absortion and glicogenolise and intestinal health, corroborating the weight gain indices. The inclusion of RPE did not cause renal histopathological lesions. Therefore, levels of 21 and 28 mL day-1 of RPE can be used in sheep diets, promoting greater final weight gain, causing positive histomorphological changes in the rumen, intestine and liver, without causing kidney or liver damage.

Supplementation of feedlot lambs with cactus cladodes as strategy to improve testicular function

The aim of this study was to evaluate the effects of diets containing cactus cladodes genotypes on plasma testosterone levels, testicular histopathological and histomorphometric parameters, and oxidative stress markers in lambs. Thirty-six male, intact Santa Inês lambs (22.0 ± 2.9 kg initial body weight), were to feedlot for 86 days. A completely randomized design was used with three dietary treatments (control diet with Tifton-85 hay as the only roughage; and two more diets with Miúda or OEM cactus cladodes partially replacing hay) and twelve replicates. There was no influence of the diets on the testicular weight (P = 0.414) and gonadosomatic index (P = 0.384) of lambs. The testosterone serum concentrations were almost twice as higher in lambs fed Miúda cactus cladodes compared to control treatment. There was greater incidence and severity of lesions in the testicular parenchyma of animals that received control diet: loosening of germ cell epithelium, germ cell desquamation and vacuolization of Sertoli cells. The seminiferous tubule diameter and height of the seminiferous epithelium were higher in lambs fed OEM cactus cladodes (P = 0.003). The tubular volume and Leydig cells volume were higher in animals fed with cactus cladodes (P < 0.05). The levels of malondialdehyde were higher in the lambs of control group compared to OEM group (P = 0.039) and the testicular concentration of nitric oxide was higher in control group (P = 0.009). The diet containing OEM cactus cladodes increased the levels of superoxide dismutase. Our results indicate that diets containing cactus cladodes promote antioxidant protection to the testicular parenchyma and preserve the spermatogenic process of lambs.

Kidney changes in lambs fed cactus pear varieties resistant to Dactylopius opuntiae as the only roughage

This study aimed to evaluate the effects of four varieties of cactus pear resistant to carmine cochineal as exclusive roughage for lambs on the biochemical, histopathological, and histomorphometric parameters of kidneys. Twenty-four castrated male crossbred lambs at eight months of age and an initial body weight of 21.0 ± 0.5 kg were distributed in a completely randomized design, with four treatments and six repetitions. The experimental treatments consisted of four diets containing Miúda cactus pear, IPA-Sertânia cactus pear, IPA-F21 cactus pear, or Orelha de Elefante Mexicana (OEM) cactus pear as the only roughage. Blood samples were collected every two weeks (14 d, 28 d, 42 d, and 56 d) to quantify serum urea and creatinine levels. After 72 days of the introduction of the tested diets, the animals were slaughtered and fragments of the kidneys were collected for histological analysis. The serum urea level was higher in animals fed a diet based on the Miúda variety (49.38 mg dL^-1), and the serum creatinine levels were lower in the last two collections (P = 0.009). The most frequent histopathological findings in the kidneys were calcification, congestion, glomerular atrophy, presence of luminal cellular debris, and nephrosis, regardless of the cactus pear variety. The Miúda cactus pear and OEM cactus pear varieties caused more severe damage to the nephron components, while the varieties IPA F-21 and IPA-Sertânia caused less significant injuries. The use of IPA-Sertânia and IPA F-21 cactus pear varieties is suggested in lamb's diets, due to the lower impact on the renal parenchyma. However, there was no expressive impairment of renal function, and there was no difference between the cactus pear varieties tested in this study on the weight gain of the animals, and they can all be used to feed feedlot sheep.

Lambs fed diets containing by-product from coconut processing: histomorphometry characteristics in the digestive and renal systems

This study aimed to evaluate the histological characteristics in the digestive and renal systems of lambs fed diets containing coconut by-product (CB). A total of 35 male lambs with an initial weight of 16.9 ± 2.93 kg were distributed in a completely randomized design with five levels of CB in the diet (0; 4.8; 9.6; 14.4 and 19.2% in total dry matter). Samples of the liver, kidney, rumen, and intestine were histomorphometrically evaluated, and the data were submitted to regression analysis, at a 5% error probability. The inclusion of CB linearly decreased the dry matter intake and caused a quadratic effect for the height of ruminal papillae, absorption area, epithelium thickness, as well as for average daily gain. The inclusion of CB linearly increased the mucous layer and reduced the submucosal layer, as well as promoted a decrease in goblet cells in the small intestine. The inclusion of CB did not influence hepatic glycogen; additionally, the histopathological examination did not reveal liver damage or congestion, vacuolization, and necrosis of the renal tissue. Therefore, our results indicate that CB can be included in lambs diet up to the level of 7.2% without causing changes in the histomorphometry characteristics of the gastrointestinal tract and changes in liver and kidney tissue that compromise animal performance.

Multi-Omics Reveals That the Rumen Transcriptome, Microbiome, and Its Metabolome Co-regulate Cold Season Adaptability of Tibetan Sheep

Tibetan sheep can maintain a normal life and reproduce in harsh environments under extreme cold and lack of nutrition. However, the molecular and metabolic mechanisms underlying the adaptability of Tibetan sheep during the cold season are still unclear. Hence, we conducted a comprehensive analysis of rumen epithelial morphology, epithelial transcriptomics, microbiology and metabolomics in a Tibetan sheep model. The results showed that morphological structure of rumen epithelium of Tibetan sheep in cold season had adaptive changes. Transcriptomics analysis showed that the differential genes were primarily enriched in the PPAR signaling pathway (ko03320), legionellosis (ko05134), phagosome (ko04145), arginine and proline metabolism (ko00330), and metabolism of xenobiotics by cytochrome P450 (ko00980). Unique differential metabolites were identified in cold season, such as cynaroside A, sanguisorbin B and tryptophyl-valine, which were mainly enriched in arachidonic acid metabolism, arachidonic acid metabolism and linolenic acid metabolism pathways, and had certain correlation with microorganisms. Integrated transcriptome-metabolome-microbiome analysis showed that epithelial gene-GSTM3 expression was upregulated in the metabolism of xenobiotics by the cytochrome P450 pathway during the cold season, leading to the downregulation of some harmful metabolites; TLR5 gene expression was upregulated and CD14 gene expression was downregulated in the legionellosis pathway during the cold season. This study comprehensively described the interaction mechanism between the rumen host and microbes and their metabolites in grazing Tibetan sheep during the cold season. Rumen epithelial genes, microbiota and metabolites act together in some key pathways related to cold season adaptation.

Cactus cladodes cause intestinal damage, but improve sheep performance

The objective of this study was to evaluate the effect of three varieties of cactus cladodes resistant to carmine cochineal on the animal performance and histology of the large intestine of sheep. Forty lambs (21.0 ± 2.0 kg body weight) were distributed in a completely randomized design, with four treatments and ten repetitions. The experimental treatments consisted of a control diet and three more diets in which part (750 g/kg) of the elephant grass hay, and all the corn were replaced by Miúda cactus cladodes, IPA-Sertânia cactus cladodes, or Orelha de Elefante Mexicana (O.E.M.) cactus cladodes. On the 60th day after the introduction of the tested diets, blood samples were collected to quantify serum magnesium (Mg²⁺) levels. After 63 days of experiment, the animals were slaughtered and fragments of the cecum and colon were collected for histopathological analysis. The inclusion of the Miúda and O.E.M. cactus cladodes in the diet caused inflammatory lesions in the cecum (100% of the animals) and in the colon (71.43% of the animals) of the sheep. The inflammation in the cecum caused by Miúda and O.E.M. cactus cladodes was considered accentuated (P = 0.009). Less voluntary water intake was observed for animals submitted to diets with cactus cladodes (P < 0.001), as well as higher water content in the feces (P < 0.001). The cactus cladodes, especially the Miúda and O.E.M. varieties, cause lesions in the tissue morphology of the cecum and colon of sheep, but improve productive performance.