Effect of forage to concentrate ratio on growth performance and feeding behavior of Thalli lambs.

The objective of the study was to evaluate the effect of forage to concentrate ratio (F:C) on growth performance and feeding behavior of Thalli lambs. For this purpose, twenty-one male Thalli lambs with initial live body weight (26.30 ± 3.02 kg) were selected and divided into three experimental groups in a randomized complete block design. The experimental duration was 12 weeks. The experimental diets were F:C (100:0), F:C (80:20), and F:C (60:40). Alfalfa hay was used as forage source. Lambs fed F:C (60:40) and F:C (80:20) diets showed higher dry matter intake (DMI), total dry matter intake (TDMI), organic matter intake (OMI), weight gain, growth rate, better feed conversion ratio, and feed efficiency as compared to the lambs fed F:C (100:0) (P < 0.05). The results also showed that crude protein (CP), ether extract (EE), and total digestible nutrient (TDN) intake were maximum in F:C (60:40)-fed lambs (P < 0.05). However, higher crude fiber (CF), neutral detergent fiber (NDF), and acid detergent fiber (ADF) intakes were seen in the F:C (100:0)-fed lambs (P < 0.05). The results of nutrient digestibilities revealed the improved OM, DM, CP, and ADF digestibilities in lambs fed with F:C (60:40) and F:C (80:20) (P < 0.05). The digestibility of NDF and CF were not affected by the all-dietary treatments (P > 0.05). Behavior results explored that eating time, and chewing time was higher in F:C (100:0)-fed lambs (P < 0.05), while standing time, lying time, and abnormal behavior were increased in lambs fed with F:C (60:40) and F:C (80:20) (P < 0.05). Based on the results, it is concluded that the addition of concentrate at 20% and 40% improves growth performance and increases DMI, TDMI, OMI, and nutrient digestibility. However, standing time, lying time, and abnormal behavior increase by feeding of the 20% and 40% concentrate. Therefore, it is suggested that the concentrate should be supplied in restricted amounts to improve lambs' welfare and normal behavior without influencing their performance.

Responses of energy balance, physiology, and production for transition dairy cows fed with a low-energy prepartum diet during hot season.

Twenty multiparous Chinese Holstein dairy cows calving in hot summer (S group), were compared with 20 similar control cows calving in cool autumn (C group). Diets were the same for both groups; prepartum diets had relatively low energy density. Average temperature-humidity index was 76.5 and 53.0 in summer and autumn, respectively. S group cows had significantly higher rectal temperatures (39.6 vs. 39.0 °C) and respiration rates (79.0 vs. 31.3 breaths/min) than C group, and consumed less feed (prepartum 8.0 vs. 12.3 kg/day, postpartum 16.3 vs. 21.2 kg/day). Calculated energy balance (EB) was -7.98 vs. -5.15 Mcal/day for S group prepartum and postpartum, respectively. In contrast, EB was 1.36 vs. -2.03 Mcal/day for C group prepartum and postpartum, respectively. S group produced significantly less milk than C group by 15.4 % (5.2 kg/day) and 26.8 % (10.2 kg/d) for milk yield and energy-corrected milk, respectively. Percentages of milk fat (3.28 vs. 4.29 %), protein (3.08 vs. 3.33 %), and solids-not-fat (8.46 vs. 8.78 %) were significantly lower for S group. Milk urea nitrogen (19.54 vs. 13.31 mg/dL) was significantly higher in S group. Significantly lower feed efficiency was observed in S group (1.56 vs. 1.66). During the entire transition period, S group had significantly lower circulating glucose levels. S group had significantly higher levels of nonesterified fatty acids (NEFA) prepartum, but after 14 days in milk, NEFA was significantly lower. We conclude that increasing dietary energy density during transition period (especially prepartum) is necessary to minimize adverse effects of hot season.

Impact of Exogenous Xylanase and Phytase, Individually or in Combination, on Performance, Digesta Viscosity and Carcass Characteristics in Broiler Birds Fed Wheat-Based Diets.

The current study was conducted to evaluate the effects of stored wheat-based diet (1.5 and 2.5 years stored wheat) with and without the supplementation of xylanase and phytase enzymes in combination or individually on performance parameters, digestibility, digesta viscosity and carcass characteristics of broilers. For this purpose, a total of 640-day-old male broilers were randomly distributed to the 64 pens, and each pen had 10 birds. Two basal isocaloric and isonitrogenous diets contained 1.5 and 2.5 years stored wheat were formulated in this experiment. In the current study, experimental feeds were prepared by supplementing exogenous enzymes in both basal diets with xylanase (500 XU), phytase (500 FTU) alone or in a combination of phytase and xylanase. Performance parameters data represents that both in starter phase and finisher phase, inclusion of exogenous enzymes xylanase and phytase in both basal diets alone or in combination enhance the feed intake, and body weight gain (p < 0.05) and improve the feed conversion ratio in overall phase (p < 0.05). Similarly, supplementation of exogenous xylanase and phytase alone or in combination enhance the nutrient digestibility and reduce the digesta viscosity (p < 0.05). Based on the results of this experiment, it is concluded that supplementation of exogenous xylanase and phytase enzymes alone or in combination in wheat-based diets (stored wheat 1.5 and 2.5 years) enhance and improves the performance of birds.

Copper Nanoparticles as Growth Promoter, Antioxidant and Anti-Bacterial Agents in Poultry Nutrition: Prospects and Future Implications.

Copper (Cu) is a vital trace mineral involved in many physiological functions of the body. In the poultry industry, copper sulfate is being used as a major source of Cu. Copper in the bulk form is less available in the body, and much of its amount excreted out with feces causing environmental pollution and economic loss. The application of nanotechnology offers promise to address these issues by making nanoparticles. Copper nanoparticles (Cu-NP) are relatively more bioavailable due to their small size and high surface to volume ratio. Although, there is limited research on the use of Cu-NP in the poultry industry. Some researchers have pointed out the importance of Cu-NP as an effective alternative of chemical, anti-bacterial agents, and growth promoters. The effect of Cu-NP depends on their size, dose rate and the synthesis method. Apart from there, high bioavailability Cu-NP exhibited positive effects on the immunity of the birds. However, some toxic effects of Cu-NP have also been reported. Further investigations are essentially required to provide mechanistic insights into the role of Cu-NP in the avian physiology and their toxicological properties. This review aims to highlight the potential effects of Cu-NP on growth, immune system, antioxidant status, nutrient digestibility, and feed conversion ratio in poultry. Moreover, we have also discussed the future implications of Cu-NP as a growth promoter and alternative anti-bacterial agents in the poultry industry.

Temporal Dynamics in Rumen Bacterial Community Composition of Finishing Steers during an Adaptation Period of Three Months.

The objective of this study was to explore whether collecting rumen samples of finishing steers at monthly intervals differed, and whether this difference or similarity varied with diets. For these purposes, 12 Chinese Holstein steers were equally divided into two groups. The dietary treatments were either standard energy and standard protein (C) or low energy and low protein (L). Rumen samples were obtained on day 30, day 60 and day 90 from both dietary treatments and were analyzed by using 16S rRNA gene sequencing. The results showed that monthly intervals had no effect on the richness and evenness of the rumen bacterial community in the two diets. However, taxonomic difference analysis (relative abundance >0.5%) revealed that the relative abundance of three phyla (Proteobacteria, Fibrobacteres and Cyanobacteria) and six genera (Rikenellaceae_RC9_gut_group, Ruminococcaceae_NK4A214_group, Fibrobacter, Eubacterium_coprostanoligenes_group, Ruminococcaceae_UCG-010 and Ruminobacter) were significantly different between monthly sampling intervals, and the difference was prominent between sampling in the first month and the subsequent two months. Moreover, the differences in abundances of phyla and genera between monthly sampling intervals were affected by diets. Analysis of similarity (ANOSIM) showed no significant differences between monthly sampling intervals in the C diet. However, ANOSIM results revealed that significant differences between the first month and second month and between the first month and third month were present in the L diet. These results indicated that temporal dynamics in rumen bacterial community composition did occur even after an adaptation period of three months. This study tracked the changes in rumen bacterial populations of finishing cattle after a shift in diet with the passage of time. This study may provide insight into bacterial adaptation time to dietary transition in finishing steers.

Dynamic Variations in Fecal Bacterial Community and Fermentation Profile of Holstein Steers in Response to Three Stepwise Density Diets.

The objective of this study was to track the dynamic variations in fecal bacterial composition and fermentation profile of finishing steers in response to three stepwise diets varied in energy and protein density. A total of 18 Holstein steers were divided into three groups in such a way that each group contained six animals and received one of three stepwise dietary treatments. Dietary treatments were C = standard energy and protein diet, H = high energy and protein diet, and L = low energy and protein diet. Animals were fattened for 11 months with a three-phase fattening strategy. Fecal samples were collected to evaluate the dynamics of fecal fermentation and bacterial composition in response to dietary treatments and fattening phases using 16S rRNA gene sequencing. Fecal acetate, propionate, and butyrate increased with increasing density of diet and as the fattening phase continued. The relative abundances of Firmicutes and Bacteroidetes dominated and showed 56.19% and 33.58%, respectively. Higher dietary density decreased the fecal bacterial diversity, Firmicutes to Bacteroidetes ratio, and the relative abundances of Ruminococcaceae_UCG-005, Rikenellaceae_RC9_gut_group, and Bacteroides, whereas higher dietary density increased the abundance of Prevotella_9. Our results indicated that both fecal fermentation profile and bacterial composition share a time-dependent variation in response to different dietary densities. This knowledge highlights that both diet and fattening phase impact fecal fermentation profile and bacterial composition, and may provide insight into strategies to reduce fecal contamination from the origin by optimizing diet and fattening time.

Effect of calcium salt of long-chain fatty acids and alfalfa supplementation on performance of Holstein bulls.

The purpose of this study was to assess the effects of calcium salt of long-chain fatty acids (CSFA) and alfalfa on beef cattle in the late fattening. 48 Holstein bulls were selected and randomly divided into 4 groups, feeding four dietary that Leymus chinensis with (LC) or with no (LN) 2.4% CSFA, and alfalfa replaced 50% Leymus chinensis with (AC) or with no (AN) 2.4% CSFA. The results indicated that alfalfa improved the feed conversion rate (P < 0.05). CSFA increased serum low density lipoprotein cholesterol, and reduced the cooking loss of Longissimus muscle (P < 0.05). CSFA and alfalfa reduced Acetate/Propionate. Alfalfa and CASF had significant additive effects on the apparent digestibility of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, organic matter and rumen fermentation for acetate, isobutyrate, butyrate, isovalerate, total volatile fatty acids (P < 0.05). CSFA increased microbial diversity index when compared with alfalfa (P < 0.05), but no significant differences were detected in bacterial genera abundances among diets. The relative abundances of rumen bacterial genera have significant correlation with apparent digestibility of nutrients, rumen fermentation characteristics and serum biochemical parameters (P < 0.05). These results comprehensively evaluated the additive effects of alfalfa and CSFA on the application in Holstein bulls.

Effects of replacing Leymus chinensis with whole-crop wheat hay on Holstein bull apparent digestibility, plasma parameters, rumen fermentation, and microbiota.

Twelve Holstein bulls were used in a 4 × 4 Latin square design to investigate the effects of using whole-crop wheat hay (WCWH) as a substitute for Leymus chinensis (LC) on apparent digestibility, plasma parameters, ruminal fermentation, and microbial communities. Experimental treatments were four proportions of WCWH, 0, 33, 67, and 100%, as a substitute for LC (WCWH0, WCWH33, WCWH67, and WCWH100, respectively). The WCWH100 group showed a higher nutritional intake of crude protein (CP) and higher apparent digestibility of organic matter (OM), CP, and ether extract (EE) than the WCWH0 group (P < 0.05). Urea N, NH3-N, isobutyrate and isovalerate levels were higher (P < 0.05) in the WCWH100 group than in the WCWH0 group. 16S rRNA high-throughput sequencing analysis revealed similarities in the community composition, species diversity and relative abundance of dominant bacteria at the phylum and genus levels among the four groups. Collectively, our data indicated that WCWH can be used to replace LC in the diet of finishing dairy bulls without having a negative impact on apparent digestibility, plasma parameters, and ruminal bacteria composition. These results offer the first deep insight into the effects of replacing LC with WCWH on the performance parameters and rumen microbiota in Holstein bulls, and may aid in ruminant farming.