Animal Production Science最新文献

The Biennial Conference of Recent Advances in Animal Nutrition – Australia was held on 27–28 July 2023. The special issue contains latest research in the field of animal nutrition across the most economically significant animal species, including poultry, pigs, sheep, cattle, companion animals and aquaculture.

This study assesses the monetary value of product quality information, specifically feedback from slaughter and production methods, within the Australian beef and sheep meat supply chains.

The primary objective was to investigate the value assigned by supply chain actors to product quality information, measured as willingness to pay for receiving it or willingness to accept payment for providing it. The study also aimed to explore how the value of this information varies based on information quality and quantity.

A contingent valuation approach was employed, utilising survey data from 104 producers. Logit models were used to identify the factors influencing meat producers’ willingness to accept payment and willingness to pay.

Over one-third of cattle and sheep producers expressed interest in receiving feedback from slaughter information and providing production methods information. Production methods information had the highest mean value at the premium information quality and quantity level, with values of AU$20.49/head in the beef industry and AU$10.13/head in the sheep industry. Conversely, feedback from slaughter information had the lowest mean value at the low information quality and quantity level, with values of AU$0.83/carcass in beef and AU$0.14/carcass in sheep. Farmers’ experience and education level significantly influenced their willingness to accept payment and willingness to pay for product quality information.

A significant proportion of producers within the Australian beef and sheep meat supply chains express a desire to provide or pay for product quality information. The value assigned to this information demonstrates a positive relationship with higher information quality and quantity. However, variations in expressed value of different information types, and the influence of farmer and farm characteristics, suggest the presence of chain failures that disrupt information valuation.

These findings have important implications for improving the performance of the red meat supply chains. Understanding the factors that influence the valuation of product quality information allows stakeholders to develop targeted strategies to enhance the efficiency and effectiveness of information exchange. This may involve addressing chain failures, and implementing measures to ensure consistent and accurate valuation of information. Ultimately, these improvements can contribute to enhanced decision-making processes and overall supply chain performance in the Australian beef and sheep meat industry.

Meat quality is increasingly being paid more attention by customers and enterprises. However, the modern pursuit of pork production has led to a decline in pork quality. Muscle fibre type is one of the important factors affecting meat quality that can be used as a key control point.

This study set out to assess the effects of dietary guanidinoacetic acid (GAA) on the growth performance, meat quality, postmortem energy metabolism, and muscle fibre types of finishing pigs.

In total, 180 healthy Duroc × Landrace × Meishan cross castrated male pigs with the similar weight (average 90 kg) were randomly divided into three treatments, with five replicates (pens) per treatment and 12 pigs per pen, including a GAA-free basal diet and basal diet with 0.05% or 0.10% GAA for 15 days.

In longissimus thoracis muscle, the results indicated that GAA supplementation decreased the drip loss and the cooking loss in 0.10% GAA group. Meanwhile, in semitendinosus muscle, 0.10% GAA addition increased pH_45 min, and decreased the cooking loss. Additionally, GAA addition increased the content of ATP and AMP in semitendinosus muscle. The mRNA expressions of MyHC-I and MyHC-IIa were increased, whereas MyHC-IIx and MyHC-IIb were decreased. Moreover, in longissimus thoracis muscle, GAA addition promoted the mRNA expressions of CaM and NFATc1; in semitendinosus muscle, dietary GAA up-regulated the CnA and NFATc1 mRNA expressions.

GAA addition improved the meat quality, enhanced postmortem energy metabolism and promoted the conversion of fast-muscle fibre to slow-muscle fibre via activating the CaN/NFAT signalling.

The addition of GAA can improve the meat quality of post-slaughter finishing pigs and provide a theoretical basis for the application of GAA in livestock production.

Supplementing a leucaena-based diet with locally available energy sources is an important strategy to extend the use of leucaena, increase liveweight (LW) gain of Bali cattle and increase profit for the smallholder.

This study was conducted to evaluate the effect of various local energy supplements in leucaena-based diets on the LW gain of Bali cattle and income-over-feed costs (IOFC).

Forty male Bali cattle were divided into five treatment groups (n = 8) and each was fed one of the following diets: (A) control diet, including leucaena ad libitum, with corn stover at 0.5% DM LW and mineral mix, (B) control + cassava meal at 1.0% DM LW, (C) control + cassava peel at 1.0% DM LW, (D) control + cassava peel and corn grain mix at 1.0% DM LW or (E) control + commercial feed at 1.0% DM LW. The experiment was run for 140 days, which included a 20-day adaptation period. Parameters measured included intake, digestibility, imbibed-water intake, LW gain, rumen and faecal parameters, feed conversion and IOFC.

Supplementation of local energy sources in combination with leucaena and corn stover diets increased LW gain of male Bali cattle above that of the control diet (P < 0.05). The bulls receiving the cassava peel and corn mix supplement had the highest LW gain (0.57 ± 0.09 kg/day), which was associated with an increase in digestible organic-matter intake (DOMI). There were no treatment differences (P > 0.05) in the rumen parameters (rumen fluid pH, rumen ammonia-N concentration and volatile fatty acids) and all parameters were optimum for rumen digestion.

The addition of local energy supplements supplied at 1% of LW improved growth rate and extended the use of a limited amount of leucaena and provided a higher IOFC.

Replacing approximately 40% of leucaena with energy sources can have three benefits, including an increase in LW gain, an increased capacity of farmers to feed more cattle per hectare and an increased income per cattle being fattened. This can increase the production scale and subsequent farmer income, provided that the energy sources are available at affordable prices and obtainable.

DNA metabarcoding strategy was used to sequence the 16S rRNA region of ruminal fluid samples from Nellore cattle fed with concentrate-rich diets in response to modulatory effect of buffering additives calcarea seaweed (Lithothamnium calcareum) and sodium bicarbonate.

Besides characterising the richness and diversity indices of rumen bacterial community, the impact of potentially acidogenic diets on rumen pH, blood parameters, and short-chain fatty acid profile (SCFA) was investigated for which four male Nellore cattle were used, distributed in a 4 × 4 Latin square (treatments × periods). Treatments comprised the same highly concentrated basal diet, and were as follows: T1, without additive (CON); T2, inclusion of 90 g of sodium bicarbonate (BIC); T3, inclusion of 90 g of L. calcareum (L90); and T4, inclusion of 45 g of L. calcareum (L45). Data were analysed in R, in which diversity and abundance at gender level were analysed using Friedman’s test, with means being adjusted by False Discovery Rate (FDR) correction. The analyses of pH, biochemical parameters and SCFA were analysed using Scott–Knott test and means were evaluated with a significance level of 10% (P < 0.10).

We identified 1474 operational taxonomic units (OTUs) belonging to 52 genera and 16 phyla of bacteria domain. The results showed that bacterial microbiota were dominated by Firmicutes (44.12%), Bacteroidetes (28.29%), and Proteobacteria (5.88%). Animals fed with L90 demonstrated greater abundance and ruminal diversity for the Prevotella genus (P < 0.07% and P < 0.09% respectively), whereas cattle supplemented with L45 demonstrated greater diversity of the Fibrobacter genus (P < 0.05). There were differences in molar proportion for acetic (P < 0.07%) and valeric (P < 0.03%) acids in the period before feeding. Higher blood lactate concentrations were observed in animals supplemented with L45 (P < 0.06%), while animals that received treatments L90 and BIC presented lower levels of blood lactate. This metabolite was lower in animals fed with 90 g of sodium bicarbonate and L. calcareum daily. These treatments also reduced the concentration of acetic acid and increased that of valeric acid, and improved ruminal diversity.

Our results supported this choice to improve ruminal function, with a great prospective of better weight-gain performance in Nellore cattle.

Adding fibre to the diet is one of the factors that help the growth and development of the digestive system of pullets during the rearing period. Insoluble-fibre inclusion enhances the grinding competence and functionality of gizzards and increases the retention time of digesta in the gastrointestinal tract.

The aim of this study was to investigate the interaction effects of insoluble fibre and the physical form of feed.

The interactive effect of two levels of sunflower hull (SH, 0 and 40 g/kg) and two feed forms (mash and pellet) on the growth of Hy-Line-W36 laying pullets from hatching until 8 weeks of age was investigated. For this purpose, 640 1-day-old chicks were randomly assigned to 64 cages.

Insoluble fibre had no effect on performance. Birds offered pelleted feed had a higher overall daily weight gain and daily feed intake than did those fed mash feed. A significant interaction between SH inclusion and feed form was observed for daily feed intake from 0 to 2 weeks. The pullets fed with mash feed without SH had a heavier weight of the gizzard than did the others. Feeding pelleted diets reduced caecum weight and the length of jejunum and ileum. Fibre inclusion resulted in a lower crypt depth in the jejunum. The jejunal villus height and muscle-layer thickness were higher in pellet-fed pullets. Feeding pelleted diets increased the tibia length and tibiotarsal index. The lowest propionate content of caecum was recorded in pellet-fed pullets without SH.

Overall, the inclusion of SH in diets had no significant effect on performance but improved the morphology of the intestine. Feeding pelleted diets improved the growth performance and intestinal morphology of pullets.

Compared to mash diets, feeding pelleted diets improved the performance. Adding fiber to the diet improves intestinal structure, which helps improve digestion and absorption of nutrients. Also, feed pelleting technology improves the effective parameters of the gastrointestinal tract in laying pullets. Also, the use of pelleted feed compared to mesh is associated with improved economic efficiency.

The proximity of rail corridors to livestock production enterprises poses potential risks to welfare and production. The association between these factors and production have been extensively investigated. This review aims to assess the potential impact on the basis of existing data in a livestock production context. Due to expansion of freight rail networks through agricultural land, there is a need to investigate potential impacts of rail (including train and track) noise, vibration and visual disturbance on the physiology and behaviour of the livestock and subsequent production traits. Additionally, the factors influencing the impact on animals were characterised broadly as noise, vibration, and visual and spatial disturbance. This information was used to develop conceptual frameworks around the contribution of rail impact on allostatic load, animal welfare and production. Placing rail noise in the context of other, known, noise impacts showed that proximity to the rail line will determine the impact of noise on the behaviour and physiology of the animal. Thresholds for noise levels should be determined on the basis of known noise thresholds, taking into account the impact of noise on allostatic load. Further research is recommended to investigate the behavioural, physiological and production impacts on livestock from proximity to rail corridors. Current literature suggests that the allostatic load will vary depending on the proximity of the animal to the source of stimulus, the type, size or level of stimuli, habituation and the individual animal variation in response to the stimuli.

Wagyu Feeder Check is a genomic-based tool designed to provide genomic estimated breeding values (GEBV) for five feedlot growth and carcase traits. At present, Wagyu Feeder Check is based on a reference population of 8316 genotyped and phenotyped Australian fullblood (FB; N = 2120) Wagyu and Wagyu-crossed (XB; N = 6196) cattle, principally Wagyu × Angus F1 animals.

We provide technical details behind the development of the Wagyu Feeder Check and validate the ability of its GEBV to predict differences in performance of Wagyu cattle in daily weight gain at feedlot, carcase weight, carcase eye muscle area, carcase marbling score and carcase rump fat at the P8 site.

Data supplied from eight commercial supply chains across Australia was used to generate GEBV using mixed-model equations that incorporated a genomic relationship matrix build with 82 504 autosomal markers. The bias, dispersion, and accuracy of the GEBV were evaluated using a four-way cross-validation scheme where, in each turn, the phenotypes from a random 1549 (or 25%) XB cattle were set as missing.

The genomic estimate of the Wagyu content in the FB and XB population averaged 99.12% and 59.55%, respectively, and with most of the non-Wagyu content associated with Angus. The estimates of heritability (± s.e.) were 0.497 ± 0.016, 0.474 ± 0.004, 0.347 ± 0.014, 0.429 ± 0.003 and 0.422 ± 0.003 for daily weight gain at feedlot, carcase weight, eye muscle area, marbling and rump fat, respectively. Averaged across the four XB validation populations, the accuracy of GEBV was 0.624, 0.634, 0.385, 0.620, and 0.526 for the same set of traits.

Genomic predictions generated by Wagyu Feeder Check can predict differences in feedlot and carcase performance of Australian Wagyu cattle. Given the large content of Angus in the XB population, further research is required to determine the predictive ability of GEBV in Wagyu × Bos indicus and Wagyu × dairy animals.

Commercial feedlot operators finishing animals with a strong Wagyu breed component will benefit from using Wagyu Feeder Check for decision making.

The Western Australian (WA) Government has set ambitious emission reduction targets and is developing strategies to reduce emissions across the state economy, including agriculture.

This study determined the product carbon footprint (CF) and total emissions of the WA beef industry, to establish a baseline for emission reduction planning.

A cradle-to-gate attributional life-cycle assessment with a reconciled livestock inventory of herd numbers and turnoff, was used. Emission reduction strategies were examined and included herd management, enteric-methane mitigation, and removals via carbon sequestration in vegetation and soils.

Modelled livestock numbers were found to be 36% higher than reported in the Australian Bureau of Statistics (ABS), resulting in an emission profile of 4.7 million tonnes (Mt) of carbon dioxide equivalent (CO₂-e) (excluding land use (LU) and direct LU change (dLUC)). This profile was 26% higher than emissions reported in state inventories. LU and dLUC were estimated to be a greenhouse-gas removal of −2.6 Mt CO₂-e, although with high uncertainty. The mean CF for WA was 15.3 kg CO₂-e per kg liveweight (LW) (excluding LU and dLUC). State-wide removals from LU and dLUC were estimated to be −8.5 kg CO₂-e/kg LW. The CF was 11.7, 19.2 and 18.2 kg CO₂-e/kg LW for the Agricultural, Kimberley and Arid regions respectively. The implementation of herd-management strategies and anti-methanogenic supplements resulted in a maximum 25% reduction.

Herd productivity and market specifications were key drivers of regional differences in CF. Opportunities exist to reduce the CF in northern herds through diverting cattle to Australian backgrounding and feedlot supply chains to reach slaughter weight at a younger age. Adoption of anti-methanogenic feed supplements were important; however, achieving major reductions in the next decade will rely on removals via carbon sequestration in soil and vegetation.

Considering the magnitude of removals and elevated uncertainty in this result, further research and new datasets are needed to refine this analysis. New datasets are required to accurately report livestock numbers and track and reduce future GHG emissions from this higher baseline. Technical, cost and adoption barriers will need to be addressed by developing actionable pathways to achieve emission reduction in the mid- to long term.