Effect of level of dietary neutral detergent fibre on the ultrastructure of M cells and mucosa integrity in rabbits’ appendix

An important constraint of in situ degradability studies is the need to analyse a high number of samples and often with insufficient amount of residue, especially after the longer incubations of high-quality forages, that impede the study of more than one nutritional component. Near-infrared spectroscopy (NIRS) has been established as a reliable method for predicting composition of many entities, including forages and other animal feedstuffs. The objective of this work was to evaluate the potential of NIRS for predicting the crude protein (CP) and neutral detergent fibre (NDF) concentration in rumen incubation residues of permanent and sown temperate pastures in a vegetative stage. In situ residues (n = 236) from four swards were scanned for their visible-NIR spectra and analysed for CP and NDF. Selected equations developed by partial least-squares multivariate regression presented high coefficients of determination (CP = 0.99, NDF = 0.95) and low standard errors (CP = 4.17 g/kg, NDF = 7.91 g/kg) in cross-validation. These errors compare favourably to the average concentrations of CP and NDF (146.5 and 711.2 g/kg, respectively) and represent a low fraction of their standard deviation (CP = 38.2 g/kg, NDF = 34.4 g/kg). An external validation was not as successful, with R2 of 0.83 and 0.82 and a standard error of prediction of 14.8 and 15.2 g/kg, for CP and NDF, respectively. It is concluded that NIRS has the potential to predict CP and NDF of in situ incubation residues of leafy pastures typical of humid temperate zones, but more robust calibrations should be developed.

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Australian and Spanish scientists are collaborating in the domestication of tedera: young Merino sheep grazing a monoculture of tedera in autumn showed preference for certain accessions but no signs of ill health

Crop and Pasture Science ◽

10.1071/cp13059 ◽

2013 ◽

Vol 64 (4) ◽

pp. 399 ◽

Cited By ~ 8

Author(s):

C. Oldham ◽

D. Real ◽

H. J. Bailey ◽

D. Thomas ◽

A. Van Burgel ◽

...

Keyword(s):

Selection Index ◽

Blood Analysis ◽

Water Soluble ◽

Soluble Carbohydrates ◽

In Vitro Digestibility ◽

Sheep Grazing ◽

Neutral Detergent Fibre ◽

Relative Preference ◽

Condition Score ◽

Acid Detergent Fibre

We hypothesised (i) that sheep grazing a monoculture of tedera (Bituminaria bituminosa (L.) C.H. Stirton var. albomarginata and var. crassiuscula) would not show signs of photosensitisation or ill health, and (ii) that when given free grazing choice they would show a repeatable preference for certain accessions of tedera related to their chemical composition. We tested this by grazing a group of young merino wethers on a monoculture containing seven accessions of tedera for 21 days. General health was assessed via daily visual checks for skin pinkness on the nose and ears, weekly measures of liveweight, condition score, and blood analysis compared with a group of control sheep fed wheaten hay ad libitum. The Chesson–Manly selection index was used to examine the relative preference of sheep for the seven accessions of tedera over the 21 days. Each accession of tedera was sampled weekly to estimate the dry matter on offer, and these samples were also analysed for crude protein, neutral detergent fibre, acid detergent fibre, in vitro digestibility, water soluble carbohydrates, minerals, and concentrations of the furanocoumarins psoralen and angelicin. None of the sheep showed any signs of ill health, with all blood parameters being within the normal reference range. All sheep gained weight and body condition over the 21 days. The difference in the rate of gain in condition score in favour of the sheep grazing tedera over the 21 days (0.014 v. 0.002 unit/sheep.day) was significant (P < 0.001). Sheep showed repeated preference for accessions T31 and T43 (α >0.143). Nutritive value of all accessions of tedera was high. However, only acid detergent fibre and neutral detergent fibre affected the relative preference of the sheep (P < 0.05) and they were only weakly correlated (r2 = 0.208 and 0.165, respectively). We conclude that there are accessions of tedera that are preferred by sheep that could be used to fill the autumn feed gap experienced in the south of Western Australia without any risk to the health of the sheep.

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Performance, carcass traits and meat quality of lambs fed with different roughage:concentrate ratios associated with variable physically effective neutral detergent fibre content

The Journal of Agricultural Science ◽

10.1017/s0021859621000459 ◽

2021 ◽

pp. 1-11

Author(s):

L. de O. Queiroz ◽

A. M. Barbosa ◽

G. B. Mourão ◽

M. A. Fonseca ◽

L. F. B. Pinto ◽

...

Keyword(s):

Fatty Acids ◽

Particle Size ◽

Meat Quality ◽

Average Daily Gain ◽

Carcass Traits ◽

Faecal Excretion ◽

Neutral Detergent Fibre ◽

Fatty Acids Profile ◽

Colour Parameter

Abstract This study evaluated the effect of roughage:concentrate (R:C) ratio associated with a variable particle size of physically effective neutral detergent fibre (peNDF8) in the forage (Tifton-85 hay) on the performance, carcass traits and meat quality of lambs. Seventy-two 4-month-old, non-castrated Santa Ines male lambs (23.5 ± 2.32 kg BW) were distributed in a completely randomized design, in a 2 × 2 factorial arrangement [two peNDF8 hay particle sizes (13 and 6 mm) and two R:C ratios (700:300 and 500:500 g/kg DM total)]. DMI, DM, NFC and TDN digestibility's, N-intake and N-faecal excretion were affected by the R:C ratio (P < 0.05). However, the N-retained was not affected by the studied variables (P > 0.05). It was observed an interaction (P < 0.05) between the peNDF8 and R:C ratios for final BW, average daily gain (ADG), colour parameters and pH 24 h. The lower roughage ratio provided greater (P < 0.05) concentrations of C14:1, C16:1–cis9, C18:1–cis9, ΣMUFA, Σn–6:Σn–3 and hypocholesterolemic/hypercholesterolemic index, enzymatic activity Δ9desaturase-C16 and -C18. Lambs fed a lower roughage diet had improved performance and feed efficiency, however, presented reduced polyunsaturated fatty acids (PUFA) concentrations in the meat, especially Σn–3 family. Higher roughage diet and larger peNDF8 particle size improved the concentrations of PUFA while decreased Σn–6:Σn–3 ratio in meat. Larger peNDF8 particle size associated with higher roughage proportion, have reduced animal performance however, it increased protein concentration, a* and C* colour parameter without affecting fatty acids profile of Longissimus lumborum muscle.

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Co-expression of vimentin and cytokeratins in M cells of rabbit intestinal lymphoid follicle-associated epithelium

The Histochemical Journal ◽

10.1007/bf01043285 ◽

1992 ◽

Vol 24 (1) ◽

pp. 33-39 ◽

Cited By ~ 53

Author(s):

Mark A. Jepson ◽

Caroline M. Mason ◽

Mark K. Bennett ◽

Nicholas L. Simmons ◽

Barry H. Hirst

Keyword(s):

Lymphoid Follicle ◽

M Cells ◽

Follicle Associated Epithelium

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Interactions of Viruses and Microparticles with Apical Plasma Membranes of M Cells: Implications for Human Immunodeficiency Virus Transmission

The Journal of Infectious Diseases ◽

10.1086/314800 ◽

1999 ◽

Vol 179 (s3) ◽

pp. S441-S443 ◽

Cited By ~ 24

Author(s):

Marian R. Neutra

Keyword(s):

Human Immunodeficiency Virus ◽

Plasma Membranes ◽

Virus Transmission ◽

Human Immunodeficiency Virus Transmission ◽

M Cells ◽

Immunodeficiency Virus

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Correlation of the startle reflex and Mauthner cell auditory responses in unrestrained goldfish

Journal of Experimental Biology ◽

10.1242/jeb.66.1.243 ◽

1977 ◽

Vol 66 (1) ◽

pp. 243-254 ◽

Cited By ~ 9

Author(s):

S. J. Zottoli

Keyword(s):

Stainless Steel ◽

Startle Reflex ◽

Sound Stimulus ◽

M Cells ◽

M Cell ◽

Mauthner Cell ◽

Auditory Responses ◽

Cell Electrode ◽

Steel Electrodes

Stainless-steel electrodes were implanted near the left or right. Mauthner cells (M-cells) of goldfish to determine if these cells can initiate the startle reflex evoked by a brief sinusoidal sound stimulus. Recordings of the M-cell extracellular spike were obtained for the duration of 10 experiments. Fish with chronic implants were allowed to free-swim and exposed to at least 10 consecutive sound stimuli consisting of 2 cycles of 200 Hz. Seventy-three startle responses were analysed. In 34 cases the implanted M-cell electrode was contralateral to the contracting musculature, and in each of these cases, a M-cell spike preceded the EMG response by 1-1-2-1 ms. In the reamining 39 cases the electrode was ipsilateral to the active musculature, and the M-cell only fired in one of these trails. There were no startle responses and no M-cell firings in an additional 52 tests. Since the M-cell activates contralateral motoneurones, the results indicate it is responsible for initiation of the startle reflex.

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Rabbit M cells and dome enterocytes are distinct cell lineages

Journal of Cell Science ◽

10.1242/jcs.114.11.2077 ◽

2001 ◽

Vol 114 (11) ◽

pp. 2077-2083

Author(s):

Hugues Lelouard ◽

Alain Sahuquet ◽

Hubert Reggio ◽

Philippe Montcourrier

Keyword(s):

Lymphoid Tissues ◽

M Cells ◽

Relative Distribution ◽

M Cell ◽

Epithelial Surface ◽

Cell Lineages ◽

Proliferative Zone ◽

Early Appearance ◽

Distinct Cell ◽

Constant Distribution

We have studied the M cell origin and differentiation pathway in rabbit gut-associated lymphoid tissues. Micro-dissected domes and epithelium isolated by ethylene diamine tetra acetic acid detachment allowed us to view the whole epithelial surface from the bottom of crypts to the top of domes. We used monoclonal antibodies specific to the apex of either M cells or dome enterocytes, lectins, and antibodies to vimentin in appendix, distal Peyer’s patches and caecal patches. The earliest vimentin-labeled M cells were observed in the BrdU-positive proliferative zone of dome-associated crypts. Gradual differentiation of the M cell vimentin cytoskeleton started at this site to progressively give rise to the first pocket-forming M cells in the upper dome. Therefore, these mitotic cells of the crypts appear as the direct precursors of M cells. In addition to an early appearance of M cell markers, a regular mosaic-like relative distribution of M cells and dome enterocytes was already detected in the vicinity of crypts, similar to that observed on the lateral surface of domes where functional M cells lie. This constant distribution implies that there is no trans-differentiation of enterocytes to M cells along the crypt-dome axis. Together, these observations provide very strong evidence in favor of an early commitment in crypts of M cell and enterocyte distinct lineages.

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