Influence of maize genotypes and harvest stages on in-silo fermentation quality and nutritional value of corn silage during hot summer condition of the tropics.

The aim of the experiment was to evaluate the potential of promising summer maize genotypes and optimal stage of harvesting these genotypes for ensiling in terms of dry matter (DM), starch, and crude protein (CP) yields, silage fermentation quality, nutrients profile, total digestible nutrients, metabolizable energy (ME) content, Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate (CHO) subfractions composition, in vitro DM digestibility (DMD) and in situ starch degradation characteristics. Six maize genotypes were chosen for the study: DK9108 from Monsanto, P30Y87, P3939 from Pioneer, QPM-300 (quality protein maize) and W94 from the International Maize and Wheat Improvement Center (CIMMYT), and a local cultivar, Afgoii, from the Cereal Research Institute (Persabaq, KP). A total of 72 plots (8 m × 10 m) were blocked in three replicate fields, and within each field, each genotype was sown in four replicate plots according to a randomized complete block design. For the data analysis, the Proc-Mixed procedure of Statistical Analysis System with repeated measure analysis of variance was used. The DM yield was strongly influenced (P < 0.001) by maize genotypes, varying from 12.6 to 17.0 tons/ha. Except for total CHO and ammonia nitrogen (NH3-N), the contents of all measured chemical components varied (P < 0.001) among the genotypes. Further comparison revealed that, genotype P3939 had a higher (P < 0.05) content of CP (7.27 vs. 6.92%), starch (36.7 vs. 27.9%), DMD (65.4 vs. 60.0%), ME (2.51 vs. 2.30 Mcal/kg) and lactic acid (5.32 vs. 4.83%) and lowest content of NDF (37.3 vs. 43.1%), pH (3.7 vs. 4.10) compared to the local cultivar (Afgoii). Advancement of post-flowering maturity from 25 to 35% DM (23 to 41 days after flowering (DAF)) increased (P < 0.05) the DM yield (10.4 to 17.8 tons/ha), starch content (29.1 to 35.0%), DMD (65.3 to 67.3%) and ME (2.34 to 2.47 Mcal/kg), and decreased (P < 0.001) the contents of CP (7.42-6.73%), NDF (48.8-38.5%), pH (4.10 to 3.60), NH3-N (8.93-7.80%N) and effective degradability of starch (95.4 to 89.4). Results showed that for higher yields and silage nutritional and fermentation quality, maize crops should be harvested at whole crop DM content of 30-35% (34 to 41 DAF). It was further concluded that genotype P3939 is the most suitable summer maize genotype for silage production in terms of yields and silage nutritional and fermentation quality under the hot environmental conditions of the tropics.

Effects of selenium enrichment on fermentation characteristics, selenium content and microbial community of alfalfa silage.

BACKGROUND: Selenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage. RESULTS: In this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05). CONCLUSION: This study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.

Responses of nutrient utilization, rumen fermentation and microorganisms to different roughage of dairy buffaloes.

Dairy buffaloes are typically fed a high-forage, low-quality diet with high fiber. These conditions result in an inherent energy and protein inefficiency. In order to make full and rational use of feed resources and improve the production level and breeding efficiency of dairy buffaloes, the effects of various roughages on nutrient digestibility, ruminal fermentation parameters, and microorganisms in dairy buffaloes were studied in this experiment. Three ternary hybrid buffaloes, with an average body weight of 365 ± 22.1 kg, were selected and fitted with permanent rumen fistulas. They were fed six different diets, each consisting of 1 kg concentrate supplement and one of six types of roughage, including alfalfa hay (A diet), oat hay (O diet), whole corn silage (W diet), king grass (K diet), sugarcane shoot silage (S diet), and rice straw hay (R diet) according to an incomplete Latin square design of 3 × 6, respectively. The pre-feeding period of each period was 12 d. From day 13 to 15 was the official experimental period. During the prefeeding period, free feed intake for each roughage was determined, and during the experiment, the roughage was fed at 90% of the voluntary feed intake. Digestion and metabolism tests were carried out using the total manure collection method to determine the feed intake and fecal output of each buffalo, and to collect feed and fecal samples for chemical analysis. On day 15, rumen fluid samples were collected two hours after morning feeding to determine rumen fermentation parameters and bacterial 16 S rRNA high-throughput sequencing was performed. The results showed that DM and OM digestibility were greatest for the W diet and lowest for the S diet. The rumen pH of the O diet was significantly greater than that of the W diet. The concentration of rumen fluid NH3-N (mg/dL) increased with increased CP content. The concentration of total volatile fatty acids (mmol/L) in the rumen decreased with increased NDF content but increased with increased NFC content. The relative abundances of Bacteroidetes, Firmicutes, and Spirochaetes were 57.03-74.84%, 14.29-21.86%, and 0.44-1.43% in the different quality roughage groups. Bacteroidetes were mainly Prevotellaceae1 and Rikenellaceae RC_gut_group with relative abundances of 30.17-45.75% and 3.23-7.82%. The relative abundance of Patescibacteria and Spirochaetes decreased with increasing roughage quality. These results provide a theoretical and practical basis for evaluating the nutritional value of dairy buffalo feed, utilizing feed resources, matching rations, feeding scientifically, and protecting animal health.

Portability of genomic predictions trained on sparse factorial designs across two maize silage breeding cycles.

KEY MESSAGE: We validated the efficiency of genomic predictions calibrated on sparse factorial training sets to predict the next generation of hybrids and tested different strategies for updating predictions along generations. Genomic selection offers new prospects for revisiting hybrid breeding schemes by replacing extensive phenotyping of individuals with genomic predictions. Finding the ideal design for training genomic prediction models is still an open question. Previous studies have shown promising predictive abilities using sparse factorial instead of tester-based training sets to predict single-cross hybrids from the same generation. This study aims to further investigate the use of factorials and their optimization to predict line general combining abilities (GCAs) and hybrid values across breeding cycles. It relies on two breeding cycles of a maize reciprocal genomic selection scheme involving multiparental connected reciprocal populations from flint and dent complementary heterotic groups selected for silage performances. Selection based on genomic predictions trained on a factorial design resulted in a significant genetic gain for dry matter yield in the new generation. Results confirmed the efficiency of sparse factorial training sets to predict candidate line GCAs and hybrid values across breeding cycles. Compared to a previous study based on the first generation, the advantage of factorial over tester training sets appeared lower across generations. Updating factorial training sets by adding single-cross hybrids between selected lines from the previous generation or a random subset of hybrids from the new generation both improved predictive abilities. The CDmean criterion helped determine the set of single-crosses to phenotype to update the training set efficiently. Our results validated the efficiency of sparse factorial designs for calibrating hybrid genomic prediction experimentally and showed the benefit of updating it along generations.

Effects of inoculation and dry matter content on microbiome dynamics and metabolome profiling of sorghum silage.

Sorghum forage was ensiled for 90 days at two dry matter (DM) contents (27 vs. 39%) without or with Lactiplantibacillus plantarum inoculation. On day 90 of fermentation, silages were sampled to assess the microbial community dynamics and metabolome profile. L. plantarum inoculation improved silage quality, as shown by a lower pH and greater acetic acid concentration. Loss of DM remained unaffected by L. plantarum inoculation but was greater in low- vs. high-DM sorghum silages (14.4 vs. 6.62%). The microbiome analysis revealed that Pseudomonas congelans represented the dominant species of the epiphytic microbiota in both low- and high-DM sorghum forage before ensiling. However, L. buchneri represented the dominant species at the end of ensiling. Ensiling fermentation resulted in distinct metabolic changes in silages with varying DM content. In low-DM silages, ensiling fermentation led to the accumulation of 24 metabolites and a reduction in the relative concentration of 13 metabolites. In high-DM silages, ensiling fermentation resulted in an increase in the relative concentration of 26 metabolites but a decrease in the concentration of 8 metabolites. Compared to non-inoculated silages, L. plantarum inoculation resulted in an increased concentration of 3 metabolites and a reduced concentration of 5 metabolites in low-DM silages. Similarly, in high-DM silages, there was an elevation in the relative concentration of 3 metabolites, while a decrease in 7 other metabolites. Ten metabolites with bio-functional activity were identified, including chrysoeriol, isorhamnetin, petunidin 3-glucoside, apigenin, caffeic acid, gallic acid, p-coumaric acid, trans-cinnamic acid, herniarin, and 3,4-dihydroxy-trans-cinnamate. This study presents a comprehensive analysis of microbiome and metabolome profiling of sorghum forage during ensiling as a function of DM content and L. plantarum inoculation, with a particular emphasis on identifying metabolites that may possess bio-functional properties. KEY POINTS: • DM loss was not different by L. plantarum but higher in low- vs. high-DM silage. • L. buchneri dominated ensiling, regardless of DM level. • 10 metabolites with bio-functional activity were identified.

The use of Lentilactobacillus buchneri PJB1 and Lactiplantibacillus plantarum MTD1 on the ensiling of whole-plant corn silage, snaplage, and high-moisture corn.

Experiments were conducted over a 3-yr period to evaluate the effects of bacterial inoculants on the fermentation profile and aerobic stability of whole-plant corn silage (WPC), snaplage (SNA), and high-moisture corn (HMC). Whole-plant corn was inoculated with Lentilactobacillus buchneri PJB1 in combination with Lactiplantibacillus plantarum MTD1 or with Lpb. plantarum alone (experiments 1 and 2). Snaplage (experiment 3) and HMC (experiments 4 and 5) were inoculated with Len. buchneri in combination with Lpb. plantarum or with Len. buchneri alone. After inoculation, the feedstuffs were ensiled in 7.57-L silos and stored at 21 ± 2°C for 30 or 90 d. In experiment 5, silage was subjected to air stress for 2 h every 2 wk through 42 d and then for 2 h/wk until 90 d and had samples analyzed for their bacterial community composition by metagenomics. Overall, in all experiments, silages inoculated with Len. buchneri alone or in combination with Lpb. plantarum had more acetic acid and 1,2-propanediol and fewer yeasts than uninoculated silages. After 30 d of ensiling, inoculation with Len. buchneri alone or in combination with Lpb. plantarum did not affect the aerobic stability of SNA, but it slightly increased the stability of WPC and markedly improved the stability of HMC. After 90 d of ensiling, inoculation with Len. buchneri alone or in combination with Lpb. plantarum markedly improved the aerobic stability of WPC, SNA, and HMC. In experiment 5, inoculation increased the relative abundance (RA) of Lactobacillaceae and reduced the RA of Enterobacteriaceae and Leuconostocaceae in HMC at 30 and 90 d and the RA of Clostridiaceae in non-air-stressed HMC at 90 d. Air-stressed HMC inoculated with Len. buchneri had less lactic acid, more acetic acid and 1,2-propanediol, and markedly greater aerobic stability than uninoculated air-stressed HMC at 90 d. In conclusion, inoculation with Len. buchneri PJB1 alone or in combination with Lpb. plantarum MTD1 increased the production of acetic acid and 1,2-propanediol, inhibited yeasts development, and improved the aerobic stability of WPC, SNA, and HMC. In HMC, inoculation markedly improved aerobic stability as soon as after 30 d of ensiling, and after 90 d, inoculation improved stability even under air stress conditions.

Effects of a genetically modified corn hybrid with α-amylase and storage length on fermentation profile and starch disappearance of whole-plant corn silage and earlage.

Two experiments were conducted to evaluate the effects of a genetically modified corn hybrid with α-amylase expressed in the kernel (AMY) on fermentation profile, aerobic stability, nutrient composition, and starch disappearance of whole-plant corn silage (WPCS) and earlage. Both hybrids, AMY and an isogenic corn hybrid (ISO), were grown in 10 replicated plots (5 for WPCS and 5 for earlage). Samples of each plot were collected at harvest, homogenized, and divided into 5 subsamples which were randomly assigned to 5 storage lengths (0, 30, 60, 90, and 120 d). Both datasets (WPCS and earlage), were analyzed separately as a completely randomized block design in a factorial arrangement of treatments, with a model including the fixed effects of hybrid, storage length, and their interaction, and the random effect of block. Minor differences on fermentation profile were observed between AMY and ISO for WPCS and earlage. An interaction between hybrid and storage length was observed for DM losses in WPCS, where losses were similar at 30, 60 and 90 d, but lower for AMY compared with ISO at 120 d. No effect of hybrid was observed on yeast and mold counts for WPCS or earlage. The aerobic stability of WPCS was greater for AMY than ISO. For earlage, AMY had greater DM losses and aerobic stability than ISO. An interaction between hybrid and storage length was observed for ammonia-N in both WPCS and earlage, where ammonia-N was similar at 0 d but greater for AMY than ISO throughout later storage lengths. A similar interaction was observed for water-soluble carbohydrates (WSC) concentrations in WPCS, where ISO had greater WSC than AMY at 0 d but was similar throughout later storage lengths. However, AMY earlage had a greater WSC concentration throughout storage length, but a lesser magnitude after ensiling. Starch concentration was greater for AMY than ISO in WPCS and earlage. Greater starch disappearances at 0 h and 6 h were observed for ISO in WPCS and earlage. Minor effects on fermentation profile, microbial counts, aerobic stability and nutrient composition suggests that AMY can be ensiled for prolonged periods with no concerns for undesirable fermentation or nutrient losses. However, in situ starch disappearance was lower for AMY compared with ISO.

Forage sources in total mixed rations early in life influence performance, metabolites, and behavior of dairy calves.

The objective of this study was to evaluate effects of forage inclusion and sources on performance, metabolism, and feeding behavior of dairy calves. Forty-eight Holstein calves were blocked and randomly assigned to 1 of 4 dietary treatments according to sex and BW at 28 d of life to determine the effects of feeding forage sources (ensiled and dry), with different quality on performance, metabolites, and behavior. Treatments consisted of a no-forage coarsely ground starter (CON); or total mixed ration (TMR) containing 7.5% on a dry matter (DM) basis of Tifton hay of either medium quality (MH) or low quality (LH); or 10% on a DM basis of corn silage (CS). During the first 28 d of life, all calves received 3 L of whole milk twice daily, a commercial pelleted starter and no forage, and water ad libitum. After that, the solid diet was changed to the respective dietary treatments. Calves were gradually weaned from 52 to 56 d of age, and followed for 14 d postweaning. Individual solid feed and milk intakes were recorded daily, and BW and metabolic indicators of intermediate metabolism were recorded weekly. Behavior was recorded, and the analysis was conducted on wk 7 (preweaning) and 10 (postweaning). Solid feed intake increased at wk 7 and 8 when MH, LH, and CS were included in TMR; the same results were observed postweaning. The diets did not affect the average daily gain and BW, but the feed efficiency increased with the CON diet. The ß-hydroxybutyrate concentration was greater in calves receiving TMR-containing forage than CON diet. Furthermore, calves supplemented with forage had a greater rumination time. In conclusion, all forage sources included in the TMR showed feed intake and behavior benefits, reinforcing the need for fiber from forage in pre- and postweaning diets.

Replacing the forage portion of the ration with triticale hay improves the performance of Holstein dairy cows.

The aim of the present study was to assess the effect of replacing the forage portion (alfalfa, corn silage, and barley straw) in the diet of lactating Holstein cows with triticale hay (TH, × Triticosecale L.) on DMI, digestibility, ruminal fermentation variables, estimated microbial-N synthesis (EMNS), and milk production and composition. Eight Holstein cows were used in a replicated Latin square design (two 4 × 4 squares) with four 28-d periods and 4 treatments, including a TH-free diet (control), and diets replacing 33%, 66%, and 100% of the forage portion with TH. Cows were fed ad libitum with 10% carryover during the experimental periods. Intakes and in vivo digestibilities of dry matter, organic matter, crude protein, and ash-free neutral detergent fiber, rumen pH, ammonia-N, total and individual short-chain fatty acids, protozoa, and bacteria populations were evaluated using specific methods. Moreover, in vitro total gas and methane release and in vivo urinary purine derivatives, EMNS, milk production, and composition were measured. The results showed that TH diets lowered DMI, compared with the control. Apparent digestibilities of DM, OM, CP, and NDF increased with dietary TH inclusion. The addition of TH instead of the diet forage portion increased in vivo rumen pH; acetic, propionic, valeric, and isovaleric acids concentrations; cellulolytic bacteria number; and in vitro gas production. In vivo rumen ammonia-N, short-chain fatty acids, butyric acid, in vivo and in vitro total protozoa and Entodiniinae numbers, and in vitro methane production decreased with increasing dietary levels of TH instead of the forage portion. The dietary addition of TH did not affect milk yield, protein, and lactose, but increased fat-corrected milk, milk fat, fat-corrected milk:DMI ratio, and milk yield:DMI ratio. Milk urea N decreased, but urinary purine derivatives excretion and EMNS increased with increasing levels of TH in the diet. For variables with significant changes, except for isovaleric acid, there was a linear response of animals to increasing levels of TH in the diet. Results suggest that TH, which is grown with less water compared with alfalfa, corn forage, and straw, is a potential alternative to those forages by increasing milk production efficiency, milk fat, and decreasing methane emission.

Effects of complete substitution of dietary grain and protein sources with by-products on the production performance of mid-lactation dairy cows fed diets based on barley silage under heat-stress conditions.

This study evaluated the effects of replacing cereal grains and soybean meal with by-products (BY) on production performance, nutrient digestibility, ruminal fermentation, nutrient recovery, and eating and chewing behavior of moderate-producing dairy cows under heat-stress conditions. Twelve multiparous Holstein cows (116.7 ± 12.01 d in milk; 42.7 ± 5.06 kg/d milk yield; 665 ± 77 kg body weight; mean ± SD) were used in a replicated 3 × 3 Latin square with 28-d periods (21 d for diet adaptation and 7 d for sampling and data collection). Cows were fed a total mixed ration containing a 39.2:60.8 ratio of forage to concentrate throughout the experiment. All diets were formulated to be isoenergetic and isonitrogenous, with different concentrates. Diets were (1) control diet based on cereal grains (CON: ground corn and ground barley, plus soybean meal); (2) sugar-rich BY diet (S-BY-CM: beet pulp, citrus pulp, and liquid molasses, plus canola meal); and (3) cereal grain BY diet (CG-BY: rice bran, corn germ meal, wheat bran, barley sprout, and broken corn). Our results showed that replacing grains with BY increased neutral detergent fiber intake and digestibility but decreased starch intake, human-edible energy, and human-edible protein. Milk yield and dry matter intake (DMI) decreased more in cows fed the CG-BY diet compared with the other 2 treatments. In contrast, no significant differences were observed between the CON and S-BY-CM diets in terms of milk yield and DMI. The S-BY-CM diet increased energy-corrected milk production compared with the CG-BY diet (36.2 vs. 34.3 kg/d), but CG-BY enhanced feed conversion efficiency compared with the other 2 treatments. Although the S-BY-CM diet prolonged the eating and sorting of small particles, neither of the dietary treatments affected chewing activity or ruminal pH 4 h after feeding. Furthermore, both diets containing BY contributed to an increase in milk fat content in comparison to the CON group. Additionally, the CG-BY and S-BY-CM diets demonstrated better performance than the CON diet in terms of human-edible feed conversion efficiency for protein and energy. The results indicated that S-BY-CM can completely replace barley and corn grain in the diet of mid-lactating dairy cows exposed to heat-stress conditions without any negative effect on production and ruminal pH. However, the inclusion of CG-BY did impair DMI, milk yield, and digestibility of nutrients and is not recommended during heat-stress conditions.

Reducing dietary protein and supplementation with starch or rumen-protected methionine and its effect on performance and nitrogen efficiency in dairy cows fed a red clover and grass silage-based diet.

The increasing cost of milk production, in association with tighter manure N application regulations and challenges associated with ammonia emissions in many countries, has increased interest in feeding lower crude protein (CP) diets based on legume silages. Most studies have focused on alfalfa silage, and little information is available on low-CP diets based on red clover silage. Our objectives were to examine the effects of dietary CP content and supplementing a low-CP diet with dietary starch or rumen-protected Met (RPMet) on the performance, metabolism, and nitrogen use efficiency (NUE; milk N output/N intake) in dairy cows fed a red clover and grass silage-based diet. A total of 56 Holstein-Friesian dairy cows were blocked and randomly allocated to 1 of 4 diets over a 14-wk feeding period. Diets were based on red clover and grass silages at a ratio of 50:50 on a dry matter (DM) basis and were fed as a total mixed ration, with a 53:47 ratio of forage to concentrate (DM basis). The diets were formulated to supply a similar metabolizable protein (MP) content, and had a CP concentration of either 175 g/kg DM (control [CON]) or 150 g/kg DM (low-protein [LP]), or LP supplemented with either additional barley as a source of starch (LPSt; +64 g/kg DM) or RPMet (LPM; +0.3 g/100 g MP). At the end of the 14-wk feeding period, 20 cows (5 per treatment) continued to be fed the same diets for a further 6 d, and total urine output and fecal samples were collected. We observed that dietary treatment did not affect DM intake, with a mean of 21.5 kg/d; however, we also observed an interaction between diet and week with intake being highest in cows fed LPSt in wk 4 and CON in wk 9 and 14. Mean milk yield, 4% fat-corrected milk, and energy-corrected milk were not altered by treatment. Similarly, we found no effect of dietary treatment on milk fat, protein, or lactose content. In contrast, milk and plasma urea concentrations were highest in cows fed CON. The concentration of blood plasma ß-hydroxybutyrate was highest in cows receiving LPM and lowest in LPSt. Apparent NUE was 28.6% in cows fed CON and was higher in cows fed any of the low-protein diets (LP, LPSt, or LPM), with a mean value of 34.2%. The sum of milk fatty acids with a chain length below C16:0 was also highest in cows fed CON. We observed that dietary treatment did not affect the apparent whole-tract nutrient digestibility of organic matter, N, neutral detergent fiber, and acid detergent fiber, with mean values of 0.785, 0.659, 0.660, and 0.651 kg/kg respectively, but urinary N excretion was approximately 60 g/d lower in cows fed the low-CP diets compared with CON. We conclude that reducing the CP content of red clover and grass silage-based diets from 175 to 150 g/kg DM while maintaining MP supply did not affect performance, but reduced the urinary N excretion and improved NUE, and that supplementing additional starch or RPMet had little further effect.

Turning weeds into feed: Ensiling Calotropis gigantea (Giant milkweed) reduces its toxicity and enhances its palatability for dairy cows.

Calotropis gigantea (Giant milkweed, GM) has the potential to be utilized as a new feed additive for ruminants, however, the presence of unpalatable or toxic compounds decreases animal feed intake. This study aimed to valorize GM as a potential new feed resource through the chemical and microbial biotransformation of toxic compounds that will henceforth, make the plant palatable for cows. After GM's ensiling using fermentative bacteria, the plant was sampled for UHPLC-MS/MS to analyse the metabolomic changes. Illumina Miseq of the 16 S rRNA fragment genes and ITS1 were used to describe the microbial composition and structure colonizing GM silage and contributing to the biodegradation of toxic compounds. Microbial functions were predicted from metataxonomic data and KEGG pathways analysis. Eight Holstein dairy cows assigned in a cross-over design were supplemented with GM and GM silage to evaluate palatability and effects on milk yield and milk protein. Cows were fed their typical diet prior to the experiment (positive control). After ensiling, 23 flavonoids, 47 amino acids and derivatives increased, while the other 14 flavonoids, 9 amino acids and derivatives decreased, indicating active metabolism during the GM ensiling process. Lactobacillus buchneri, Bacteroides ovatus, and Megasphaera elsdenii were specific to ensiled GM and correlated to functional plant metabolites, while Sphingomonas paucimobilis and Staphylococcus saprophyticus were specific to non-ensiled GM and correlated to the toxic metabolite 5-hydroxymethylfurfural."Xenobiotics biodegradation and metabolism", "cancer overview" and "neurodegenerative disease" were the highly expressed microbial KEGG pathways in non-ensiled GM. Non-ensiled GM is unpalatable for cows and drastically reduces the animal's feed intake, whereas ensiled GM does not reduce feed intake, milk yield and milk protein. This study provides essential information for sustainable animal production by valorizing GM as a new feed additive.

Harvest Timing of Standing Corn Using Near-Infrared Reflectance Spectroscopy.

Harvesting corn at the proper maturity is important for managing its nutritive value as livestock feed. Standing whole-plant moisture content is commonly utilized as a surrogate for corn maturity. However, sampling whole plants is time consuming and requires equipment not commonly found on farms. This study evaluated three methods of estimating standing moisture content. The most convenient and accurate approach involved predicting ear moisture using handheld near-infrared reflectance spectrometers and applying a previously established relationship to estimate whole-plant moisture from the ear moisture. The ear moisture model was developed using a partial least squares regression model in the 2021 growing season utilizing reference data from 610 corn plants. Ear moisture contents ranged from 26 to 80 %w.b., corresponding to a whole-plant moisture range of 55 to 81 %w.b. The model was evaluated with a validation dataset of 330 plants collected in a subsequent growing year. The model could predict whole-plant moisture in 2022 plants with a standard error of prediction of 2.7 and an R2P of 0.88. Additionally, the transfer of calibrations between three spectrometers was evaluated. This revealed significant spectrometer-to-spectrometer differences that could be mitigated by including more than one spectrometer in the calibration dataset. While this result shows promise for the method, further work should be conducted to establish calibration stability in a larger geographical region.

Insights into the phage community structure and potential function in silage fermentation.

The virus that infects bacteria known as phage, plays a crucial role in the biogeochemical cycling of nutrients. However, the community structure and potential functions of phages in silage fermentation remain largely unexplored. In this study, we utilized viral metagenomics (viromics) to investigate the types, lifestyles, functions, and nutrient utilization patterns of phages in silage. Our findings indicated a high prevalence of annotated phages belonging to Caudovirales and Geplafuvirales, as well as unclassified phages in silage. The predominant host types for these phages were Campylobacterales and Enterobacterales. Virulent phages dominated the silage environment due to their broader range of hosts and enhanced survival capabilities. All identified phages present in silage were found to be non-pathogenic. Although temperate and virulent phages carried distinct genes associated with nutrient cycling processes, the shared genes (prsA) involved in carbon metabolism underscore the potential significance of phages in regulating carbon metabolism in silage. Overall, our findings provide a valuable foundation for further exploring the complex interactions between phages and microorganisms in regulating silage fermentation quality.

Bioaugmented ensiling of sweet sorghum with Pichia anomala and cellulase and improved enzymatic hydrolysis of silage via ball milling.

Sweet sorghum, as a seasonal energy crop, is rich in cellulose and hemicellulose that can be converted into biofuels. This work aims at investigating the effects of synergistic regulation of Pichia anomala and cellulase on ensiling quality and microbial community of sweet sorghum silages as a storage and pretreatment method. Furthermore, the combined pretreatment effects of ensiling and ball milling on sweet sorghum were evaluated by microstructure change and enzymatic hydrolysis. Based on membership function analysis, the combination of P. anomala and cellulase (PA + CE) significantly improved the silage quality by preserving organic components and promoting fermentation characteristics. The bioaugmented ensiling with PA + CE restructured the bacterial community by facilitating Lactobacillus and inhibiting undesired microorganisms by killer activity of P. anomala. The combined bioaugmented ensiling pretreatment with ball milling significantly increased the enzymatic hydrolysis efficiency (EHE) to 71%, accompanied by the increased specific surface area and decreased pore size/crystallinity of sweet sorghum. Moreover, the EHE after combined pretreatment was increased by 1.37 times compared with raw material. Hence, the combined pretreatment was demonstrated as a novel strategy to effectively enhance enzymatic hydrolysis of sweet sorghum.

Synergistic effects of ferulic acid esterase-producing lactic acid bacteria, cellulase and xylanase on the fermentation characteristics, fibre and nitrogen components and microbial community structure of Broussonetia papyrifera during ensiling.

BACKGROUND: The high fibre content of whole plants of Broussonetia papyrifera limits its efficient utilization. Ferulic acid esterase (FAE), in combination with xylanase, can effectively cleave the lignin-carbohydrate complex, promoting the function of cellulase. However, little is known about the impact of these additives on silage. To effectively utilize natural woody plant resources, FAE-producing Lactiplantibacillus plantarum RO395, xylanase (XY) and cellulase (CE) were used to investigate the dynamic fermentation characteristics, fibre and nitrogen components and microbial community structure during B. papyrifera ensiling. RESULTS: Broussonetia papyrifera was either not treated (CK) or treated with FAE-producing lactic acid bacteria (LP), CE, XY, LP + CE, LP + XY or LP + CE + XY for 3, 7, 15, 30 or 60 days, respectively. In comparison with those in the CK treatment, the L. plantarum and enzyme treatments (LP + CE, LP + XY and LP + XY + CE), especially the LP + XY + CE treatment, significantly increased the lactic acid concentration and decreased the pH and the contents of acid detergent insoluble protein and NH3 -N (P < 0.05). Enzyme addition improved the degradation efficiency of lignocellulose, and a synergistic effect was observed after enzyme treatment in combination with LP; in addition, the lowest acid detergent fibre, neutral detergent fibre, hemicellulose and cellulose contents were detected after the LP + CE + XY treatment (P < 0.05). Moreover, CE, XY and LP additions significantly improved the microbial community structure, increased the relative abundance of Lactiplantibacillus and Firmicutes, and effectively inhibited undesirable bacterial (Enterobacter) growth during ensiling. CONCLUSION: FAE-producing L. plantarum and the two tested enzymes exhibited synergistic effects on improving the quality of silage, which indicates that this combination can serve as an efficient method for improved B. papyrifera silage utilization. © 2023 Society of Chemical Industry.

Mixed ensiling plus nitrate destroy fiber structure of rape straw, increase degradation, and reduce methanogenesis through in vitro ruminal fermentation.

BACKGROUND: Better utilization of rape straw can provide alternative strategies for sustainable ruminant and food production. The research reported here investigated changes in the carbohydrate composition of rape straw as a result of mixed ensiling with whole-crop corn or inoculated with nitrate, and the consequent effects on ruminal fermentation through in vitro batch culture. The three treatments included: rape straw and corn silage (RSTC), and ensiling treatment of rape straw with whole-crop corn (RSIC) or with calcium nitrate inoculation (RSICN). RESULTS: Ensiling treatment of rape straw and whole-crop corn or plus nitrate enriched lactic acid bacteria and lactate. The treatments broke the fiber surface connections of rape straw, leading to higher neutral detergent soluble (NDS) content and lower fiber content. Ensiling treatments led to greater (P < 0.05) dry matter degradation (DMD), molar proportions of propionate and butyrate, relative abundance of the phylum Bacteroidetes and genus Prevotella, and lower (P < 0.05) methane production in terms of g kg-1 DMD, molar proportions of acetate, and lower acetate to propionate ratio than the RSTC treatment. The RSICN treatment led to the lowest (P < 0.05) hydrogen concentration and methane production among the three treatments. CONCLUSION: Ensiling treatments of rape straw and whole-crop corn destroy the micro-structure of rape straw, promote substrate degradation by enriching the phylum Bacteroidetes and the genus Prevotella, and decrease methane production by favoring propionate and butyrate production. Nitrate inoculation in the ensiling treatment of rape straw and whole-crop corn further decreases methane production without influencing substrate degradation by providing an additional hydrogen sink. © 2023 Society of Chemical Industry.

Toward making a high-quality silage from common reed (Phragmites australis).

The effects of the addition of molasses (5 and 10% of dry matter: DM basis; M5 and M10 respectively) with or without urea (2%; U2, U2 + M5 and U2 + M10) on chemical and mineral composition, silage quality, microbial populations, buffering capacity and fermentation/digestion characteristics of common reed (Phragmites australis) ensiled under anaerobic conditions were investigated. The additives changed the silage quality of common reed compared with the control. Crude protein content was significantly (p < 0.0001) increased in urea-containing silages, whereas ash-free neutral detergent fibre concentration decreased in M10 compared with the control (p = 0.05). Treatment with 2% urea (U2) resulted in the reduction of most measured minerals with a severe decrease in iron concentration. The amount of gas produced after 96 h of incubation was, respectively, higher for U2, M10, U2M10, U2M5 and M5 compared with the control (p < 0.0001). Although the greatest in vitro dry matter digestibility and in vitro organic matter digestibility (96 h) were observed in U2 (p < 0.0001), no significant differences were found between U2 and M10. Supplementation with 10% molasses (M10) significantly increased lactic acid concentration, aerobic stability and total bacteria compared with other treatments (p < 0.0001). Moreover, DM loss (p = 0.0004), total yeast and mould (p < 0.0001) were significantly decreased as a result of 10% molasses treatment. Overall, it can be suggested that treating silage with 10% molasses (M10) has the potential to efficiently improve the nutritive value of common reed.

Ovarian activity, hormone profile, pro-inflammatory cytokines and reproductive performance of buffalo cows fed diets with different estrogenicity.

Buffalo cows play a vital role in milk and meat production; however, they are characterised by several reproductive disorders. Feeding diets with high oestrogenic activity may be a disrupting factor. This study aimed to evaluate the effects of feeding roughages with different oestrogenic activity on the reproductive performance of early postpartum buffalo cows. A total of 30 buffalo cows were equally stratified into two experimental groups and fed either Trifolium alexandrinum (Berseem clover, phytoestrogenic roughage) or corn silage (nonoestrogenic roughage) for 90 consecutive days. After 35 days from the beginning of the feeding treatments, buffalo cows in both groups were synchronized for oestrus using a double i.m. injection of 2 mL prostaglandin F2α , 11 days apart, subsequently, overt signs of oestrus were observed and recorded. Moreover, ovarian structures, numbers and sizes of follicles and corpora lutea, were ultrasonography examined at day-12 (represents Day 35 of feeding treatment), Day 0 (day of oestrus) and Day 11 after oestrous synchronization (mid-luteal phase). Pregnancy was diagnosed 35 days postinsemination. Blood serum samples were analysed for progesterone (P4 ), estradiol (E2 ), tumor necrosis factor (TNF-α), interlukein-1ß (IL-1ß) and nitric oxide (NO). The high performance liquid chromatography-analysis of roughages showed the abundance of isoflavones in Berseem clover, with about 58 times higher concentration than that in corn silage group. During the experimental period, the numbers of ovarian follicles of all size categories were higher in the Berseem clover group than that in the corn silage group. No significant difference in the numbers of corpora lutea was observed between both experimental groups, but lower (p < 0.05) diameter of corpus luteum was observed in the Berseem clover group than that in the corn silage group. The Berseem clover group had higher (p < 0.05) overall concentrations of blood serum E2 , IL-1ß and TNF-α, but lower (p < 0.05) overall concentrations of blood serum P4 than those recorded in the corn silage group. Oestrous rate, onset of oestrus time and oestrous duration were not significantly affected by the treatment. The conception rate was significantly (p < 0.05) reduced in the Berseem clover group compared with that in the corn silage group. In conclusion, feeding roughage with a high oestrogenic activity such as Berseem clover can negatively affect the conception rate of buffalo cows. This reproductive loss seems to be associated with inadequate luteal function and P4 concentration during early pregnancy.

Impacts of red clover and sainfoin silages on the performance, nutrient utilization and milk fatty acids profile of ruminants: A meta-analysis.

Inclusion of plants rich in secondary metabolites into grass ensiling offers multiple benefits for ruminants, from improving productive performance to health-promoting effects as well as helping to reduce environment pollution. The present meta-analysis summarizes the dietary inclusion levels of red clover silage (RCS) and sainfoin silages (SS) as well as the types of silages fed to dairy cows and small ruminants. A total of 37 in vivo studies (26 articles in dairy cows and 11 articles in small ruminants) were aggregated after being strictly selected using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A mixed model methodology was used to examine our objectives. This method declares the subject 'study' as random effects and 'inclusion level' as fixed effects. Results indicated that RCS proportion was not associated with nutrient digestibility except for a quadratic effect (p < 0.05) on neutral detergent fibre digestibility. Higher RCS inclusion linearly increased (p < 0.05) nitrogen (N) intake but had no effect on dairy cows' production. Increasing RCS proportion altered milk fatty acid profile where the concentration of conjugated linolenic acid (CLA), C18:3 α-linolenic acid (ALA) and C18:0 linearly increased (p < 0.01). In small ruminants, SS proportion had no relationship with nutrient digestibility, N metabolism and growth performance (p > 0.05). However, a combination of dietary RCS + SS resulted in significantly higher (p < 0.05) CLA and ALA concentration in cow milk and average daily gain (ADG) in small ruminants compared to diets composed from either grass silage or alfalfa silage. Altogether, this meta-analysis highlights the synergistic effects of a combination of SS + RCS inclusion in improving milk fatty acids (FA) profile of dairy cows and ADG of small ruminants.