Real-Time Quantification of Crude Protein and Neutral Detergent Fibre in Pastures under Montado Ecosystem Using the Portable NIR Spectrometer

The Montado is a Mediterranean agro–forestry–pastoral ecosystem. Knowledge of pastures' nutritional value is critical for farm managers’ decision-making. Laboratory determinations are very expensive, destructive and costly, in terms of time and labour. The objective of this experimental work was to calibrate and validate a portable near-infrared spectrometer (micro-NIR) to predict the nutritive value (neutral detergent fibre, NDF and crude protein, CP) of pastures in the peak of spring 2021. Thus, a total of 87 pasture samples were collected at eight experimental fields located in the Alentejo, Southern region of Portugal. The results show good correlations between in-situ micro-NIR measurements and pasture NDF reference values (R2 of 0.73 and 0.69 for calibration and validation models, respectively), and a moderate correlation between micro-NIR measurements and pasture CP reference values (R2 of 0.51 and 0.36 for calibration and validation models, respectively). These results show the potential of this tool for the quick evaluation of pasture quality and constitute a starting point for future work, which should include the monitoring of temporal variability (throughout the entire vegetative cycle of the pasture) and spatial (with geo-referenced information) diversity of pastures characteristic of the Montado ecosystem in the Mediterranean region.

Apparent digestibility and nutritional composition of Leucaena leucocephala (Lam) leaf meal incorporated in the diets of Black Australorp and Potchefstroom Koekoek chicken breeds

The objective of the study was to determine the apparent digestibility and nutrient composition of Leucaena leucocephala leaf meal (LLM) inclusion in Black Australorp and Potchefstroom Koekoek diets. Tender and mature leaves were separately harvested from 10 individual trees and stored separately for chemical analyses. The leaves were air-dried in a well-ventilated laboratory to constant weight and milled to pass through a 1-mm sieve. A mixture of tender and mature leaves was also collected to produce a bulk leaf meal. The four iso-nitrogenous dietary treatments were 0 (control), 2.5, 5.0 and 7.5% of LLM, respectively. The apparent digestibility of two chicken breeds was also evaluated. The dry matter (DM), neutral detergent fibre (NDF), ether extract (EE), cellulose and hemicellulose of the samples did not differ between tender and mature leaves. Tender leaves had higher (P < 0.05) calcium, potassium, magnesium and sodium concentration than mature leaves. Crude protein and mimosine content were significantly (P < 0.05) higher in tender than in mature leaves. The inclusion levels of L. leucocephala leaf meal affect (P < 0.05) acid detergent fibre (ADF), neutral detergent fibre (NDF) and crude protein (CP) digestibility. Crude protein digestibility decreases as the inclusion levels of L. leucocephala increase. Both tender and mature L. leucocephala leaves have a potential nutritional value that can be used in feedstuff and can be used as a protein supplement for Black Australorp and Potchefstroom Koekoek chicken breeds.

Associative effects in diets composed of alfalfa and corn soybean concentrate fed to growing cashmere goats

The associative effects resulting from the proportions of neutral detergent fibre (NDF) and non fibre carbohydrate (NFC) were explored and assessed by in vitro gas production . Total mixed rations (TMR) composed primarily of alf a lfa and corn soybean concentrate were fed to growing cashmere goats. Treatments were defined by three proportions of NFC and NDF namely 2.00 ( TMR1), 2.35 ( TMR2), and 3.00 ( that were used to grow cashmere goats , and these TRMs were incubated for 48 h ours to evaluate their influence on associative effects. The results indicated that the associative influences of these treatments on gas production occurred within the cultures predominantly at 2 8 hours, and disappeared gradually as culture time was ex tended . TMR 2 and TMR3 incubation increased gas production compared with that observed in the other groups at all incubation times P > 0.05), and these groups exhibited positive associative effects, particularly during the early hours of incubation P <0.05 )). TMR 3 displayed the best associative effect.

In vitro and in sacco digestibility of almond hulls

The aim of this study was to determine the in vitro digestibility and in sacco disappearance of dry matter (DM) and neutral detergent fibre (NDF) in total almond hulls (TAH), pure almond hulls (PAH) or Debris. The TAH were used because there are no data on the effect of debris (non-hull material) on the nutritional value of almond hulls. Twelve samples of commercial almond hulls were used, with one subsample representing the TAH and the other subsample hand sorted to separate the hulls (PAH) from Debris. Gas production and Ankom Daisy method were used to determine in vitro digestibility, while two rumen-fistulated cows were used to measure in sacco disappearance of PAH and TAH. For in vitro digestibility, both PAH and TAH were more digestible and had greater gas production than Debris. The PAH had greater in vitro true digestibility on a DM basis and NDF digestibility at 48 and 72 h compared with TAH. Nonpareil hulls provided greater metabolizable energy (ME) concentration when compared with other almond varieties, with PAH supplying numerically more ME than TAH for both varieties. For in sacco disappearance, PAH had greater DM and NDF disappearance along with a greater rate of disappearance for NDF compared with TAH. This research demonstrated that Debris is highly indigestible; therefore, hulling, agronomic and harvesting practices should be focused on reducing Debris in commercial almond hulls to improve their nutritive value as a feedstuff for livestock.

Cultivation of housefly larvae (Musca domestica L.) as a biological method to enrich rice straw and maximise its utilisation

This study is aimed at presenting a new biological technique to enrich rice straw via the cultivation of Musca domestica (MD) and at evaluating the outcome of this technique using in vitro and in vivo studies. Rice straw was treated using molasses and water at 17.5: 0.375: 7.0 (w/v/v), respectively. The mixture was left in an open shaded area for 11 successive days to allow MD to lay eggs and produce larvae. During this time, the recorded temperature was 35.6±2.2 °C and the humidity was 49±5.7%. Rice straw treated with 4% urea (URS) and untreated rice straw (RS) were used for comparison with in vitro and in vivo MD maggot rice straw (MRS). The crude protein (CP) and ether extract (EE) contents gradually increased during the first 8 days, and then began to gradually decrease until the 11th day. In vitro studies were performed on RS, MRS and URS as a single substrate. Instead, in the in vivo studies, experimental RS was offered ad libitum to sheep, and a concentrate feed mixture was provided as pellets to cover the maintenance requirements. The volume of produced gas and the in vitro degradability of the organic matter (OM), ash-free neutral detergent fibre, and CP (P<0.05) increased with the fermentation of the mg of MRS, compared to URS, which in turn was (P<0.05) higher than that of RS incubation. The consumed MRS was significantly (P<0.05) higher than the consumed URS. At the same time, the URS consumption was highly (P<0.05) significant, compared to the RS consumption. The eating, ruminating and chewing time (min/head/d) was significantly (P<0.05) higher when RS was consumed, compared to URS and MRS. Eating a diet including MRS led to higher (P<0.05) dry matter, OM, CP, EE, neutral detergent fibre, and acid detergent fibre digestibility, than the diet containing URS, which was significantly (P<0.05) superior to the diet containing RS. The total digestible nutrients (TDN) and digestible crude protein values of the MRS-containing diet improved (P<0.05) more than that of URS, which was significantly (P<0.05) higher than RS. In short, the results indicate that MD maggots could be produced on rice straw to elevate the protein content and nutritional value of feeds. Moreover, this technique improved the feed consumption and digestion coefficients more than the treated and untreated rice straw.

Evaluation of high-concentrate diets that vary in physically effective neutral detergent fibre for finishing lambs

The objective of this research was to evaluate lamb diets with a high proportion of concentrate and various levels of physically effective neutral detergent fibre (NDF) using tropical ingredients. Four diets were formulated: D1 with 16.5% physically effective NDF (peNDF), D2 with 21.4% peNDF, D3 with 23.3% peNDF, and D4 with 24.6% peNDF. Twenty male Santa Inês lambs at four months old with an average liveweight (LW) of 18.6 ± 3.4 kg were fed for 49 days. There were no differences (P >0.05) among the diets in dry matter (DM) intake. Crude protein (CP) intake, relative to either LW or metabolic live weight (LW0.75) or LW, was greater (P ≤0.05) for D2 and D3 than for D1 or D4. Lower (P ≤0.05) NDF intake, relative to LW0.75 or LW, was lower for D1 than for the other diets. Selection indexes (SIs) were similar (P >0.05) among diets. Animals that consumed D1 had less (P ≤0.05) rumination time per bolus. Meaningful variations were not observed in performance and efficiency of finishing lambs that were related to differences in peNDF among the diets. Santa Inês lambs were able to adapt to diets with low levels of peNDF by increasing rumination time as a consequence of increased fibre consumption and greater particle size selection.

In situ rumen degradation characteristics and bacterial colonization of whole cottonseed, cottonseed hull and cottonseed meal with different gossypol content

Regarding whole cottonseed (WCS), cottonseed meal (CSM), and cottonseed hull (CSH), in situ rumen incubation was applied to determine their nutrient and gossypol degradation characteristics and bacterial colonization profile in lactating Holstein cows. Nylon bags containing the cotton by-products were incubated for 0, 6, 12, 24, 36, 48 and 72 h in the rumen, respectively. The relationship between nutrient degradability and free gossypol (FG) content were examined, and the differences in the composition and inferred gene function of the colonized microbiota were studied. As a result, CSM presented highest effective degradability of dry matter, neutral detergent fibre and acid detergent fibre, but the highest effective degradability of crude protein was found in WCS. Free gossypol disappearance rate increased significantly in the first 6 h, and it reached approximately 94% at 72 h of incubation among all samples. The level of FG did not affect nutrient degradability of cotton by-products. Significant differences were noted in attached bacterial community structure among cotton by-products after 24 h rumen incubation. Among the most abundant taxa at genus level, a greater abundance of Cercis gigantea and Succiniclasticum was observed in WCS samples, whereas the CSH and CSM samples contained a greater proportion of Prevotella 1 and Rikenellaceae RC9 gut group. The redundancy analysis revealed that the level of neutral detergent fibre, ether extract, and FG in cotton by-products were significantly positive related with the composition of the attached bacteria. Collectively, our results revealed the dynamics of degradation characteristics, and the difference in the composition of bacterial colonization. These findings are of importance for the targeted improvement of cotton by-products nutrient use efficiency in ruminants and further understanding of the gossypol degradation mechanism in the rumen.

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

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.