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The re-integration of native woody vegetation within agricultural areas has the potential to support multifunctional productive landscapes that enhance livestock welfare and restore habitat for native wildlife. As there is minimal research on this issue in Aotearoa New Zealand, this study aimed to identify species of native woody vegetation and propose spatial configurations and site designs to increase multifunctionality on a case study site. The three components of a multifunctional agricultural landscape focused on in this study were (1) enhancing foraging opportunities for livestock, (2) optimizing shade and shelter, and (3) establishing native bush bird habitat. During the first phase, sixty-three suitable species were identified and assigned scores based on the primary objectives and site constraints. This produced four optimized plant lists, one each for the three multifunctional components identified above and one combined multifunctional list incorporating those scores with additional environment and soil scores. The second phase used design thinking methodology to strategically locate these plants within an established case study site. Nine different planting configurations (three for each multifunctional component) were proposed and then, informed by site-specific opportunities and constraints, located on the case study site to produce three individual site designs. Finally, these three site designs were combined to propose an exemplar of a multifunctional agricultural landscape. The results indicate that reintegrating native woody vegetation has the potential to contribute toward multifunctional agricultural landscapes, proposing species and spatial layouts from which further investigation into livestock foraging, increased shade and shelter, and restoration of bush bird habitat can follow. This research advances sustainable land management practices by offering valuable insights into future agricultural landscape design.

The net energy (NE) system takes into account the metabolic utilisation of energy and has been proposed as a superior system for characterising the energy value of feeds. In growing pigs, the inefficiency of ME utilisation for NE (or the heat increment, HI) is dependent on many factors, among them the genotype, which implies that published NE prediction equations may not apply across all genotypes. We conducted a study to investigate the effect of two genotypes (Yorkshire-Hampshire♀ × Duroc♂; YH × D) and Large white♀ × Landrace♂; LW × LR) on heat production (HP) and NE value of a corn soybean meal-based diet fed to growing pigs. The diet met or exceeded the nutrient specifications of 20-50 kg b.w. pigs according to NRC (1998). A total of sixteen barrows were used, eight of each genotype (initial b.w. of 20.1 ± 1.1 and 19.0 ± 0.9 kg for YH ×D and LW × LR, respectively). Pigs were initially fed at 550 kcal/kg b.w.-0.60/day (high ME intake) for determination of DE and ME in metabolism crates. Thereafter, HP was measured using an indirect calorimeter at either high ME or 330 kcal/kg b.w.-0.60/day (low ME intake) to estimate fasting HP (FHP) by regression. Pigs were allowed a 3-d adaptation period at low ME intake before measurement of HP. Irrespective of the genotype, a reduction of ME intake resulted in a decrease (P < 0.0001) of HP (352 for high ME vs. 292 kcal/kg b.w.-0.60/day for low ME). Pigs of LW × LR tended (P = 0.07) to have higher HP than those of YH× D and their estimated FHP was 175 and 103 kcal/kg b.w.-0.60/day, respectively. The determined diet NE value was lower for the YHxD genotype (2,307 vs. 2633 kcal/kg DMI, P = 0.01) than for the LW × LR genotype. Pigs of LW × LR genotype showed lower (179 vs. 226 kcal/kg b.w.-0.60/day, P = 0.003) HI than YH × D genotype and were determined to retain less energy as protein (100 vs. 123 kcal/kg b.w.-0.60/day, P =0.04) and more energy as fat (73 vs. 42 kcal/kg b.w.-0.60/day, P = 0.04). The diet NE value was 96% (LW × LR) and 81% (YH × D) of the predicted NE from published equations. In conclusion, a corn-soybean meal fed at equal amounts resulted in different HP and NE value depending on genotype.

γ-aminobutyric acid (GABA) is an amino acid used for mitigating the detrimental effects of heat stress in broilers. In addition, a growing body of literature suggests that the in ovo feeding of various nutrients can enhance the post-hatch thermotolerance of broilers. Therefore, we hypothesized that the supplementation of GABA during incubation might have positive effects in heat-stressed broilers. Chicks hatched from eggs were divided into three groups described as follows: chicks hatched from eggs incubated at normal temperature and then raised under thermoneutral temperature (CON); chicks hatched from eggs incubated at normal temperature but raised under cyclic heat stress (HS) (CON+HS); and chicks hatched from eggs injected with 60 mg of GABA dissolved in 0.6 mL of distilled water but raised under cyclic HS (G10+HS). The HS was applied between 28 and 31 days of age with ambient temperatures raised from 22 ± 1 °C to 33 ± 1 °C for 6 h daily. Compared to the CON group, average daily weight gain was significantly lower in the CON+HS but not in the G10+HS group. Feed intake was significantly decreased in both the CON+HS and G10+HS groups. Compared to the CON group, plasma corticosterone levels were significantly increased in the CON+HS group, but not the G10+HS group. Hepatic mRNA levels of the acetyl-CoA carboxylase gene (ACC) were significantly reduced in the G10+HS group compared to the CON group. In addition, positive Pearson correlation coefficients were found in mRNA levels between fatty acid synthase (FAS) and nicotinamide adenine dinucleotide phosphate oxidase 1 (NOX1) (r = 0.55, p < 0.05), NOX1 and NOX4 (r = 0.65, p < 0.01), and catalase (CAT) and superoxide dismutase (SOD) (r = 0.62, p < 0.05). Taken together, the results suggest that this study can serve as a basis for future work focusing on the in ovo feeding of GABA as a technique to combat heat stress in broilers.

In order to meet consumer needs, the livestock industry is increasingly seeking natural feed additives with the ability to improve the efficiency of nutrient utilization, alternatives to antibiotics, and mitigate methane emissions in ruminants. Chitosan (CHI) is a polysaccharide with antimicrobial capability against protozoa and Gram-positive and -negative bacteria, fungi, and yeasts while naringin (NA) is a flavonoid with antimicrobial and antioxidant properties. First, an in vitro gas production experiment was performed adding 0, 1.5, 3.0 g/kg of CHI and NA under a completely randomized design. The substrate containing forage and concentrate in a 70:30 ratio on a dry matter (DM) basis. Compounds increased the concentration of propionic acid, and a significant reduction in methane production was observed with the inclusion of CHI at 1.5 g/kg in in vitro experiments (p < 0.001). In a dry matter rumen degradability study for 96 h, there were no differences in potential and effective degradability. In the in vivo study, six crossbred heifers fitted with rumen cannulas were assigned to a 6 × 6 Latin square design according to the following treatments: control (CTL), no additive; chitosan (CHI1, 1.5 g/kg DMI); (CHI2, 3.0 g/kg DMI); naringin (NA1, 1.5 g/kg DMI); (NA2, 3.0 g/kg DMI) and a mixture of CHI and NA (1.5 + 1.5 g/kg DMI) given directly through the rumen cannula. Additives did not affect rumen fermentation (p > 0.05), DM intake and digestibility of (p > 0.05), and enteric methane emissions (p > 0.05). CHI at a concentration of 1.5 g/kg DM in in vitro experiments had a positive effect on fermentation pattern increasing propionate and reduced methane production. In contrast, in the in vivo studies, there was not a positive effect on rumen fermentation, nor in enteric methane production in crossbred heifers fed a basal ration of tropical grass.

This study was conducted in order to investigate whether the presence of light or different colors of light would influence the energy expenditure and behavior of broiler chickens. Eight 8-week-old broiler chickens were adapted to a respiration chamber (Length, 28.5 cm; Height, 38.5 cm; Width, 44.0 cm) for one week prior to the initiation of the experiment. In experiment 1, energy expenditure and behavior of the chickens were analyzed in the presence or absence of light for four days. Chickens were exposed to 6 cycles of 2 h light/2 h dark period per day. In experiment 2, the broiler chickens that had been used in experiment 1 were used to evaluate the effect of 4 different wavelength light-emitting diodes (LEDs) on the energy expenditure and behavior of broiler chickens. The LEDs used in this study had the following wavelength bands; white (control), red (618 to 635 nm), green (515 to 530 nm) and blue (450 to 470 nm). The chickens were randomly exposed to a 2-h LED light in a random and sequential order per day for 3 days. Oxygen consumption and carbon dioxide production of the chickens were recorded using an open-circuit calorimeter system, and energy expenditure was calculated based on the collected data. The behavior of the chickens was analyzed based on following categories i.e., resting, standing, and pecking, and closed-circuit television was used to record these behavioral postures. The analysis of data from experiment 1 showed that the energy expenditure was higher (p<0.001) in chickens under light condition compared with those under dark condition. The chickens spent more time with pecking during a light period, but they frequently exhibited resting during a dark period. Experiment 2 showed that there was no significant difference in terms of energy expenditure and behavior based on the color of light (white, red, green, and blue) to which the chickens were exposed. In conclusion, the energy expenditure and behavior of broiler chickens were found to be strongly affected by the presence of light. On the other hand, there was no discernible difference in their energy expenditure and behavior of broiler chickens exposed to the different LED lights.

Large ruminant production in developing countries is inefficient with low growth rates and likely high greenhouse gas emissions per unit of meat or milk produced. Trials conducted in Lao PDR from 2017 to 2020, studied ad libitum supplementation for 12 weeks with 20 kg high-quality molasses nutrient blocks (Four Seasons Pty Ltd., Brisbane, Australia), that were either non-medicated; fenbendazole-medicated (Panacur100®, Coopers Australia, 5 g/kg); triclabendazole-medicated (Fasinex®, Novartis Australia, 5 g/kg or 10 g/kg, respectively); or formulated with urea (8% or 10% urea, respectively). Average daily gains were determined for access to all molasses blocks and compared with access to control blocks, no supplementation, or previously determined free-grazing baseline average daily gains (55–84 g in cattle; 92–106 g in buffalo). Productivity was significantly improved following access to all molasses blocks. Average daily gains following access to 8% urea and control blocks were calculated for three age cohorts of cattle: young calves <8 m (238–298 g), growing cattle (143–214 g) and lactating cows (179–191 g). Modelling using IPCC Inventory software model V 2.69 of published data demonstrated a conservative net abatement of 350 kg CO2e was achievable over a 200-day feeding period. An additional trial of Emissions control blocks (n = 200) distributed to farmers (n = 60) and two educational institutions were conducted. Consumption rates (156 g/day) and farmer and institutional acceptance of these blocks were similar to our published findings with other molasses blocks, confirming all formulations of blocks improved animal productivity and body condition score, with healthier animals that were easier to manage. Modelling of changes in greenhouse gas emissions intensity identified an abatement of 470 kg CO2e per Emissions control blocks consumed, delivering a total project emissions abatement of 94 t CO2e. Provision of high-quality molasses blocks significantly improved smallholder large ruminant productivity and addition of greenhouse gas reducing agents is likely to achieve impressive abatement of greenhouse gas emissions due to improved efficiency of rumen fermentation and productivity.

Avaliou-se o efeito do uso de aditivos químicos nas perdas de matéria seca, no perfil fermentativo e no valor nutritivo de silagens de cana-de-açúcar. O experimento foi realizado em delineamento inteiramente casualizado com quatro repetições por tratamento (sete tratamentos). Os seguintes aditivos foram utilizados na confecção das silagens: controle (sem aditivo), L. buchneri, óxido e carbonato de cálcio em doses de 1,0 e 1,5% da massa verde e sulfato de cálcio a 1,0% da massa verde, diluídos em 40 litros de água por tonelada de forragem. As variáveis analisadas foram: perdas totais e gasosas, produção de efluente, recuperação de matéria seca, composição química e valor nutritivo. As menores perdas fermentativas e gasosas foram observadas nas silagens com óxido ou carbonato de cálcio, que resultaram em maior taxa de recuperação de matéria seca. Da mesma forma, as silagens tratadas com estes aditivos apresentaram maior teor de carboidratos solúveis residuais e de ácido lático e reduzida fermentação alcoólica. As silagens tratadas com óxido e carbonato apresentaram, no momento da abertura, maior teor de cinzas, menor concentração de componentes fibrosos e maiores coeficientes digestibilidade da matéria seca e da matéria orgânica. O teor de proteína encontrado nessas silagens foi semelhante ao observado na forragem fresca. A ensilagem de cana-de-açúcar com L. buchneri e sulfato de cálcio possibilitou a obtenção de desempenho similar ao determinado com a silagem sem aditivos. Silagens tratadas com carbonato e óxido de cálcio apresentam maior desempenho durante o processo fermentativo.The objective of this trial was to evaluate the effects of chemical additives in the dry matter losses, fermentation profile, and nutritive value of sugar cane silages. The trial was carried out in a completely randomized experimental design with four replicates per treatment. The following additives were applied to the fresh forage during the ensiling: control (without additive), L. buchneri, calcium oxide and calcium carbonate,1.0 and 1.5% (wet basis) each, and calcium sulfate 1.0% (wet basis), all of them diluted in to 40 L of water per ton of fresh forage. The variables analyzed were: total and gaseous dry matter losses, dry matter recovery, fermentation end products, and nutritive value. The use of calcium oxide or calcium carbonate were effective in reducing dry matter losses and gaseous production and had the highest dry matter recovery rate. Both silages had also low ethanol content and, as a result, had greater concentrations of residual water soluble carbohydrates and lactic acid. The addition of calcium oxide and calcium carbonate at the time of ensiling produced silages with higher nutritive value compared with all other treatments, due to the increase of ash content and dry matter and organic digestibility and also, by reducing the fiber content. The crude protein content range was similar to the values observed in the fresh forage. The treatments with L. buchneri and calcium sulfate were ineffective in altering the fermentation process of sugar cane silages and became similar to the control silages. In summary, the overall analysis pointed out that the treatment containing calcium oxide and calcium carbonate improved the fermentation and storage process.

This study investigated the metabolizable energy (ME) intake, net energy of production (NEp), heat production (HP), efficiencies of ME use for energy, lipid and protein retention as well as the performance of broiler chickens fed diets based on cassava chips or pellets with or without supplementation with an enzyme product containing xylanase, amylase, protease and phytase. The two products, cassava chips and pellets, were analysed for nutrient composition prior to feed formulation. The cassava chips and pellets contained 2.2% and 2.1% crude protein; 1.2% and 1.5% crude fat; and 75.1% and 67.8% starch, respectively. Lysine and methionine were 0.077%, 0.075%, and 0.017%, 0.020% protein material, respectively, while calculated ME was 12.6 and 11.7 MJ/kg, respectively. Feed intake to day 21 was lower (p<0.01) on the diet containing cassava chips compared to diets with cassava pellets. Enzyme supplementation increased (p<0.01) feed intake on all diets. Live weight at day 21 was significantly (p<0.01) reduced on the diet based on cassava chips compared to pellets, but an improvement (p<0.01) was noticed with the enzyme supplementation. Metabolizable energy intake was reduced (p<0.01) by both cassava chips and pellets, but was increased (p<0.01) on all diets by enzyme supplementation. The NEp was higher (p<0.01) in the maize-based diets than the diets containing cassava. Enzyme supplementation improved (p<0.01) NEp in all the diets. Heat production was highest (p<0.01) on diets containing cassava pellets than on cassava chips. It is possible to use cassava pellets in diets for broiler chickens at a level close to 50% of the diet to reduce cost of production, and the nutritive value of such diets can be improved through supplementation of enzyme products containing carbohydrases, protease, and phytase.