Martin Gierus | University of Natural Resources and Life Sciences, Vienna (BOKU) (original) (raw)

Papers by Martin Gierus

Animal, 2018

The present study investigated the effect of hydrothermic maize processing and supplementation of... more The present study investigated the effect of hydrothermic maize processing and supplementation of amino acids (AA) in two experiments. In total, 60 barrows and 384 broilers were fed four diets including either unprocessed (T1), or hydrothermically processed maize, that is short-(T2), or long-term conditioned (LC) (T3), and subsequently expanded maize of the same batch. Assuming a higher metabolizable energy (ME) content after processing, the fourth diet (T4) contains maize processed as treatment T3, but AA were supplemented to maintain the ideal protein value. Performance, digestibility and product quality in both species were assessed. Results show that in pigs receiving T4 the average daily feed intake was lower compared with the other treatments, whereas no difference was observed in broilers. The T3 improved the feed conversion rate compared with T1 (P < 0.10) for both species. In contrast, average daily gain (ADG) (1277 g/day for T2 and 1267 g/day for T3 v. 971 g/day for T1) was only altered in pigs. The hydrothermic maize processing increased the apparent total tract digestibility (ATTD) of dry matter, starch and ether extract after acid hydrolysis. This may be a consequence of higher ATTD of gross energy in the finishing phase for both animal species, suggesting a higher ME content in diets with processed maize. The higher ME content of diets with processed maize is supported also by measurements of product quality. Supplementation of AA in T4 enhanced the loin depth in pigs as well as the amount of breast meat in broilers. Further effects of processing maize on meat quality were the reduced yellowness and antioxidative capacity (P< 0.10) for broilers, likely due to the heat damage of xanthophylls and tocopherols. Processing also increased springiness and chewiness (P < 0.10) of the broilers breast meat, whereas the loin meat of pigs showed a decreased lightness and yellowness (P < 0.10) in meat when hydrothermic processed maize was used (for T2, T3 and T4). LC processed maize (T3) showed the lowest springiness in pork, however the supplementation of AA in T4 did not show differences between the treatments. Shown results demonstrated positive effects of hydrothermic processing of maize on animal performance and digestibility in both species. However, effects on carcass characteristics and product quality differed. The negative effects on product quality could be partly compensated with the AA supplementation, whereas a change in meat colour and reduced antioxidative capacity was observed in all groups fed hydrothermic maize processing.

Animals

Swine production is of great importance worldwide and has huge economic and commercial impact. Du... more Swine production is of great importance worldwide and has huge economic and commercial impact. Due to problems with bacterial infection, the use of antimicrobials has increased in the last decades, particularly in Latin America and Asia. This has led to concerns about antimicrobial resistance, which poses risks to human health and the environment. The use of probiotic organisms has been proposed as an alternative to this use, as these beneficial bacteria can produce antimicrobial peptides, such as bacteriocins, which allow the induction of inhibitory effects against pathogenic microorganisms. Among probiotics, some bacteria stand out with the inhibition of animal pathogens. The bacteriocin-like inhibitory substances (BLISs) of Lactococcus lactis subsp. lactis strain L2, present in its cell-free supernatant, were tested against pathogenic strains isolated from pig samples, such as Escherichia coli, Salmonella enterica, Streptococcus suis, Streptococcus dysgalactiae, Staphylococcus hy...

Fig. 1: Area of research, Inner Mongolia, P.R. China Background Increasing grazing pressure on na... more Fig. 1: Area of research, Inner Mongolia, P.R. China Background Increasing grazing pressure on native grassland in Inner Mongolia, P.R. China Overgrazing and degradation (more than 80% of the typical steppe ecosystem in Inner Mongolia is degraded). Grazing not only alters the ecological functionality of the grassland but also its value for livestock farming. Aim of the present study: Analysis of grazing-induced changes in productivity and herbage quality as well as its effect on animal performance.

Animals

Physical pellet quality and AMEN concentration are strongly related to each other in broiler feed... more Physical pellet quality and AMEN concentration are strongly related to each other in broiler feeding. A study was conducted to evaluate the relationship between dietary AMEN concentration and feed processing on pellet quality, nutrient digestibility, broiler performance, serum markers, and yield of commercial cuts. Six diets were formulated. The first diet had the recommended AMEN concentration, each further diet was calculated with 40 kcal/kg less, from 0 to −200 kcal/kg, resulting in six levels for each feed phase: starter (1–14 d), grower (15–28 d), and finisher (29–35 d). These diets were processed with and without expander conditioning prior to pelleting, using an average corn particle size of 1.6 mm, ground with a roller mill. A total of 1008 one-day-old male Ross 308 broiler chickens were placed in a 6 × 2 (6 energy levels and 2 conditionings) factorial trial with six boxes as replications, with three in each broiler performance trial period. Excreta were collected 2 days bef...

Animals

During the processing of compound feed for broilers, several changes occur that affect the physic... more During the processing of compound feed for broilers, several changes occur that affect the physical and probably the nutritional properties of pellets, influencing animal performance. The effects of mill type, particle size (PS) and expander conditioning prior to pelleting (E + P) were combined to generate pellets. A 2 × 3 × 2 factorial arrangement was designed with two mill types (a hammer mill (HM) or roller mill (RM)), three PSs (0.8, 1.2 or 1.6 mm) and two E + Ps (with or without expander processing prior to pelleting), with six replications of 12 unsexed Ross 308 broilers each. All the processing lines reduced the PS from mash to finished pellets via secondary grinding, by 2.35 times on average. However, RM grinding required less electric power (p < 0.001). The intended PS (0.8, 1.2 or 1.6 mm) did not affect this energy consumption. E + P and the PS interacted for the pellet durability index (PDI) (p = 0.006). The worst PDI in the pellets was observed when a PS of 1.6 mm wit...

Animals

In a low-fibre diet destined for broilers, the effects of two lignocellulose products and soybean... more In a low-fibre diet destined for broilers, the effects of two lignocellulose products and soybean hulls were evaluated regarding their effect on ileal morphometric parameters, caecal gene expression, foot pad dermatitis, and performance. A total of 5040-day-old broilers (Ross 308) were allotted to four treatments and fattened for 36 days applying a three-phase feeding program. The control diet consisted of corn, wheat, and soybean meal. Experimental diets were supplemented with 0.8% lignocellulose product 1, 0.8% lignocellulose product 2, or 1.6% soybean hulls. Tissue samples for caecal expression of inflammation-related genes and ileal morphometries were collected on day 21. Gizzard pH and weights were recorded, and foot pad scores were evaluated at day of slaughter (day 36). In starter (day 1–10) and finisher phase (day 28–36), no effect on the performance was observed. In grower phase (day 11–27), fibre-supplemented diets showed significantly heavier body weights and daily weight...

Journal of Animal Science, 2016

INtRODUCtION Grasslands cover about 68% of Inner Mongolia, P.R. China, and have been extensively ... more INtRODUCtION Grasslands cover about 68% of Inner Mongolia, P.R. China, and have been extensively used for pastoral sheep and cattle production for centuries (Kawamura et al., 2005). Since the 1950s, transformations in the political framework have induced a shift from nomadic to sedentary livestock keeping (Jiang et al., 2006). Besides, pastoralists currently graze their sheep and cattle only on grasslands located close to their farms and use their distant areas for haymaking. An expansion of cropland and growing human and livestock populations have greatly reduced the grassland available per animal (Tong et al., 2004; Yu et al.,

Conclusions Recent modernization processes in Oman’s mountain communities have profoundly altered... more Conclusions Recent modernization processes in Oman’s mountain communities have profoundly altered traditional goat husbandry, leading to a year-round grazing of the shrinking pasture areas. The abandonment of livestock herding due to labour shortage and of the traditional coordination of pasture use among villages amplify the degradation of the natural vegetation and therefore threaten the future of the agro-pastoral goat husbandry. Materials and methods • Semi-quantitative interviews were conducted with one adult of all goat-keeping households (HH) in three villages of the central Al-Jabal-al-Akhdar region (57°40’E, 23°02’N, 1000-2000 m a.s.l., n=28) in autumn 2006. • HH composition, goat herd sizes, and labour input into goat husbandry were quantified. • Size and stocking rates of village pastures were determined in 10 map-based key informant interviews. • In September 2007, herbaceous ground cover and dry mass (DM) were estimated in 10x10m2 plots along transects at grazed (n=14) ...

The Journal of Agricultural Science, 2013

SUMMARYThe grassland steppe of Inner Mongolia is traditionally used for sheep grazing. However, o... more SUMMARYThe grassland steppe of Inner Mongolia is traditionally used for sheep grazing. However, overgrazing reduced vegetation cover in winter, thereby increasing soil erosion and consequently, degradation of the steppe vegetation. Grazing intensity (GI) is still the most important factor in pasture management. Hence, the aim of the current study was to evaluate the effect of GI on grassland and sheep performance. A grazing experiment was conducted from July until September in 2005, 2006 and 2007 in which six different GI ranging from very light (GI 1), light (GI 2), light-moderate (GI 3), moderate (GI 4) and heavy (GI 5) to very heavy (GI 6) were tested. Each GI treatment comprised two adjacent plots that were alternately used for grazing or hay-making each year. Variables measured included herbage mass (HM) and chemical composition, digestibility of ingested organic matter (dOM), organic matter intake (OMI) and live weight gain (LWG) of sheep. The HM decreased significantly with i...

Nutrient Cycling in Agroecosystems, 2012

ABSTRACT Although a significant fraction of the global soil-atmosphere exchange of greenhouse gas... more ABSTRACT Although a significant fraction of the global soil-atmosphere exchange of greenhouse gases (GHGs) occurs in semi-arid zones little is known about the magnitude of fluxes in grazed steppe ecosystems and the interference with grazing intensity. In order to assess GHG burdens and to identify options of climate-optimized livestock farming, GHG emissions of sheep grazing in Inner Mongolia steppe were analyzed. Carbon sequestration and field-fluxes of methane (CH4) and nitrous oxide (N2O) were measured at a range of steppe sites differing in grazing intensity and management, i.e. ungrazed (UG), ungrazed with hay cutting (HC), lightly grazed (LG), moderately grazed (MG), and heavily grazed (HG). In addition, GHG emissions from enteric fermentation, manure management, and farming inputs (i.e. fossil fuels) were quantified for LG, MG, and HG. Monte Carlo simulation was used to estimate uncertainty. Sheep grazing changed the net GHG balance of the steppe from a significant sink at UG (-1476 +/- A 2481 kg CO2eq ha(-1) year(-1)) to a significant source at MG (2350 +/- A 1723 kg CO2eq ha(-1) year(-1)) and HG (3115 +/- A 2327 kg CO2eq ha(-1) year(-1)). In a similar way, the GHG intensity increased from 8.6 +/- A 79.2 kg CO2eq kg(-1) liveweight gain at LG up to 62.2 +/- A 45.8 and 62.6 +/- A 46.7 kg CO2eq kg(-1) liveweight gain at MG and HG, respectively. GHG balances were predominantly determined by CO2 from changes in topsoil organic carbon. In grazing systems, CH4 from enteric fermentation was the second most important component. The results suggest that sheep grazing under the current management changes this steppe ecosystem from a sink to a source of GHGs and that grazing exclusion holds large potential to restore soil organic carbon stocks and thus to sequester atmospheric CO2. The balance between grazing intensity and grazing exclusion predominantly determines GHG balances of grass-based sheep farming in this region. Therefore, a high proportion of ungrazed land is most important for reducing GHG balances of sheep farms. This can be either achieved by high grazing intensity on the remaining grazed land or by confined hay feeding of sheep.

Antioxidants

Reports of the underlying mechanisms of dietary grape extract (GE) in overcoming weaning challeng... more Reports of the underlying mechanisms of dietary grape extract (GE) in overcoming weaning challenges in piglets have been partly inconsistent. Furthermore, evaluations of the effects of GE at weaning in comparison to those of widely used therapeutic antibiotics have been scarce. To explore the mode of action of GE in selected tissues and plasma, we evaluated gut morphology, antioxidant and inflammation indices. Accordingly, 180 weaning piglets were allocated to three treatment groups: negative control (NC), NC and antibiotic treatment for the first 5 days of the trial (positive control, PC), and NC and GE (entire trial). The villus surface was positively affected by GE and PC on day 27/28 of the trial in the jejunum and on day 55/56 of the trial in the ileum. In the colon, NC tended (p < 0.10) to increase crypt parameters compared to PC on day 55/56. The PC group tended (p < 0.10) to increase catalase activity in the ileum and decrease Cu/Zn-SOD activity in the jejunum, both co...

Animal, 2018

The present study investigated the effect of hydrothermic maize processing and supplementation of... more The present study investigated the effect of hydrothermic maize processing and supplementation of amino acids (AA) in two experiments. In total, 60 barrows and 384 broilers were fed four diets including either unprocessed (T1), or hydrothermically processed maize, that is short-(T2), or long-term conditioned (LC) (T3), and subsequently expanded maize of the same batch. Assuming a higher metabolizable energy (ME) content after processing, the fourth diet (T4) contains maize processed as treatment T3, but AA were supplemented to maintain the ideal protein value. Performance, digestibility and product quality in both species were assessed. Results show that in pigs receiving T4 the average daily feed intake was lower compared with the other treatments, whereas no difference was observed in broilers. The T3 improved the feed conversion rate compared with T1 (P < 0.10) for both species. In contrast, average daily gain (ADG) (1277 g/day for T2 and 1267 g/day for T3 v. 971 g/day for T1) was only altered in pigs. The hydrothermic maize processing increased the apparent total tract digestibility (ATTD) of dry matter, starch and ether extract after acid hydrolysis. This may be a consequence of higher ATTD of gross energy in the finishing phase for both animal species, suggesting a higher ME content in diets with processed maize. The higher ME content of diets with processed maize is supported also by measurements of product quality. Supplementation of AA in T4 enhanced the loin depth in pigs as well as the amount of breast meat in broilers. Further effects of processing maize on meat quality were the reduced yellowness and antioxidative capacity (P< 0.10) for broilers, likely due to the heat damage of xanthophylls and tocopherols. Processing also increased springiness and chewiness (P < 0.10) of the broilers breast meat, whereas the loin meat of pigs showed a decreased lightness and yellowness (P < 0.10) in meat when hydrothermic processed maize was used (for T2, T3 and T4). LC processed maize (T3) showed the lowest springiness in pork, however the supplementation of AA in T4 did not show differences between the treatments. Shown results demonstrated positive effects of hydrothermic processing of maize on animal performance and digestibility in both species. However, effects on carcass characteristics and product quality differed. The negative effects on product quality could be partly compensated with the AA supplementation, whereas a change in meat colour and reduced antioxidative capacity was observed in all groups fed hydrothermic maize processing.

Animals

Swine production is of great importance worldwide and has huge economic and commercial impact. Du... more Swine production is of great importance worldwide and has huge economic and commercial impact. Due to problems with bacterial infection, the use of antimicrobials has increased in the last decades, particularly in Latin America and Asia. This has led to concerns about antimicrobial resistance, which poses risks to human health and the environment. The use of probiotic organisms has been proposed as an alternative to this use, as these beneficial bacteria can produce antimicrobial peptides, such as bacteriocins, which allow the induction of inhibitory effects against pathogenic microorganisms. Among probiotics, some bacteria stand out with the inhibition of animal pathogens. The bacteriocin-like inhibitory substances (BLISs) of Lactococcus lactis subsp. lactis strain L2, present in its cell-free supernatant, were tested against pathogenic strains isolated from pig samples, such as Escherichia coli, Salmonella enterica, Streptococcus suis, Streptococcus dysgalactiae, Staphylococcus hy...

Fig. 1: Area of research, Inner Mongolia, P.R. China Background Increasing grazing pressure on na... more Fig. 1: Area of research, Inner Mongolia, P.R. China Background Increasing grazing pressure on native grassland in Inner Mongolia, P.R. China Overgrazing and degradation (more than 80% of the typical steppe ecosystem in Inner Mongolia is degraded). Grazing not only alters the ecological functionality of the grassland but also its value for livestock farming. Aim of the present study: Analysis of grazing-induced changes in productivity and herbage quality as well as its effect on animal performance.

Animals

Physical pellet quality and AMEN concentration are strongly related to each other in broiler feed... more Physical pellet quality and AMEN concentration are strongly related to each other in broiler feeding. A study was conducted to evaluate the relationship between dietary AMEN concentration and feed processing on pellet quality, nutrient digestibility, broiler performance, serum markers, and yield of commercial cuts. Six diets were formulated. The first diet had the recommended AMEN concentration, each further diet was calculated with 40 kcal/kg less, from 0 to −200 kcal/kg, resulting in six levels for each feed phase: starter (1–14 d), grower (15–28 d), and finisher (29–35 d). These diets were processed with and without expander conditioning prior to pelleting, using an average corn particle size of 1.6 mm, ground with a roller mill. A total of 1008 one-day-old male Ross 308 broiler chickens were placed in a 6 × 2 (6 energy levels and 2 conditionings) factorial trial with six boxes as replications, with three in each broiler performance trial period. Excreta were collected 2 days bef...

Animals

During the processing of compound feed for broilers, several changes occur that affect the physic... more During the processing of compound feed for broilers, several changes occur that affect the physical and probably the nutritional properties of pellets, influencing animal performance. The effects of mill type, particle size (PS) and expander conditioning prior to pelleting (E + P) were combined to generate pellets. A 2 × 3 × 2 factorial arrangement was designed with two mill types (a hammer mill (HM) or roller mill (RM)), three PSs (0.8, 1.2 or 1.6 mm) and two E + Ps (with or without expander processing prior to pelleting), with six replications of 12 unsexed Ross 308 broilers each. All the processing lines reduced the PS from mash to finished pellets via secondary grinding, by 2.35 times on average. However, RM grinding required less electric power (p < 0.001). The intended PS (0.8, 1.2 or 1.6 mm) did not affect this energy consumption. E + P and the PS interacted for the pellet durability index (PDI) (p = 0.006). The worst PDI in the pellets was observed when a PS of 1.6 mm wit...

Animals

In a low-fibre diet destined for broilers, the effects of two lignocellulose products and soybean... more In a low-fibre diet destined for broilers, the effects of two lignocellulose products and soybean hulls were evaluated regarding their effect on ileal morphometric parameters, caecal gene expression, foot pad dermatitis, and performance. A total of 5040-day-old broilers (Ross 308) were allotted to four treatments and fattened for 36 days applying a three-phase feeding program. The control diet consisted of corn, wheat, and soybean meal. Experimental diets were supplemented with 0.8% lignocellulose product 1, 0.8% lignocellulose product 2, or 1.6% soybean hulls. Tissue samples for caecal expression of inflammation-related genes and ileal morphometries were collected on day 21. Gizzard pH and weights were recorded, and foot pad scores were evaluated at day of slaughter (day 36). In starter (day 1–10) and finisher phase (day 28–36), no effect on the performance was observed. In grower phase (day 11–27), fibre-supplemented diets showed significantly heavier body weights and daily weight...

Journal of Animal Science, 2016

INtRODUCtION Grasslands cover about 68% of Inner Mongolia, P.R. China, and have been extensively ... more INtRODUCtION Grasslands cover about 68% of Inner Mongolia, P.R. China, and have been extensively used for pastoral sheep and cattle production for centuries (Kawamura et al., 2005). Since the 1950s, transformations in the political framework have induced a shift from nomadic to sedentary livestock keeping (Jiang et al., 2006). Besides, pastoralists currently graze their sheep and cattle only on grasslands located close to their farms and use their distant areas for haymaking. An expansion of cropland and growing human and livestock populations have greatly reduced the grassland available per animal (Tong et al., 2004; Yu et al.,

Conclusions Recent modernization processes in Oman’s mountain communities have profoundly altered... more Conclusions Recent modernization processes in Oman’s mountain communities have profoundly altered traditional goat husbandry, leading to a year-round grazing of the shrinking pasture areas. The abandonment of livestock herding due to labour shortage and of the traditional coordination of pasture use among villages amplify the degradation of the natural vegetation and therefore threaten the future of the agro-pastoral goat husbandry. Materials and methods • Semi-quantitative interviews were conducted with one adult of all goat-keeping households (HH) in three villages of the central Al-Jabal-al-Akhdar region (57°40’E, 23°02’N, 1000-2000 m a.s.l., n=28) in autumn 2006. • HH composition, goat herd sizes, and labour input into goat husbandry were quantified. • Size and stocking rates of village pastures were determined in 10 map-based key informant interviews. • In September 2007, herbaceous ground cover and dry mass (DM) were estimated in 10x10m2 plots along transects at grazed (n=14) ...

The Journal of Agricultural Science, 2013

SUMMARYThe grassland steppe of Inner Mongolia is traditionally used for sheep grazing. However, o... more SUMMARYThe grassland steppe of Inner Mongolia is traditionally used for sheep grazing. However, overgrazing reduced vegetation cover in winter, thereby increasing soil erosion and consequently, degradation of the steppe vegetation. Grazing intensity (GI) is still the most important factor in pasture management. Hence, the aim of the current study was to evaluate the effect of GI on grassland and sheep performance. A grazing experiment was conducted from July until September in 2005, 2006 and 2007 in which six different GI ranging from very light (GI 1), light (GI 2), light-moderate (GI 3), moderate (GI 4) and heavy (GI 5) to very heavy (GI 6) were tested. Each GI treatment comprised two adjacent plots that were alternately used for grazing or hay-making each year. Variables measured included herbage mass (HM) and chemical composition, digestibility of ingested organic matter (dOM), organic matter intake (OMI) and live weight gain (LWG) of sheep. The HM decreased significantly with i...

Nutrient Cycling in Agroecosystems, 2012

ABSTRACT Although a significant fraction of the global soil-atmosphere exchange of greenhouse gas... more ABSTRACT Although a significant fraction of the global soil-atmosphere exchange of greenhouse gases (GHGs) occurs in semi-arid zones little is known about the magnitude of fluxes in grazed steppe ecosystems and the interference with grazing intensity. In order to assess GHG burdens and to identify options of climate-optimized livestock farming, GHG emissions of sheep grazing in Inner Mongolia steppe were analyzed. Carbon sequestration and field-fluxes of methane (CH4) and nitrous oxide (N2O) were measured at a range of steppe sites differing in grazing intensity and management, i.e. ungrazed (UG), ungrazed with hay cutting (HC), lightly grazed (LG), moderately grazed (MG), and heavily grazed (HG). In addition, GHG emissions from enteric fermentation, manure management, and farming inputs (i.e. fossil fuels) were quantified for LG, MG, and HG. Monte Carlo simulation was used to estimate uncertainty. Sheep grazing changed the net GHG balance of the steppe from a significant sink at UG (-1476 +/- A 2481 kg CO2eq ha(-1) year(-1)) to a significant source at MG (2350 +/- A 1723 kg CO2eq ha(-1) year(-1)) and HG (3115 +/- A 2327 kg CO2eq ha(-1) year(-1)). In a similar way, the GHG intensity increased from 8.6 +/- A 79.2 kg CO2eq kg(-1) liveweight gain at LG up to 62.2 +/- A 45.8 and 62.6 +/- A 46.7 kg CO2eq kg(-1) liveweight gain at MG and HG, respectively. GHG balances were predominantly determined by CO2 from changes in topsoil organic carbon. In grazing systems, CH4 from enteric fermentation was the second most important component. The results suggest that sheep grazing under the current management changes this steppe ecosystem from a sink to a source of GHGs and that grazing exclusion holds large potential to restore soil organic carbon stocks and thus to sequester atmospheric CO2. The balance between grazing intensity and grazing exclusion predominantly determines GHG balances of grass-based sheep farming in this region. Therefore, a high proportion of ungrazed land is most important for reducing GHG balances of sheep farms. This can be either achieved by high grazing intensity on the remaining grazed land or by confined hay feeding of sheep.

Antioxidants

Reports of the underlying mechanisms of dietary grape extract (GE) in overcoming weaning challeng... more Reports of the underlying mechanisms of dietary grape extract (GE) in overcoming weaning challenges in piglets have been partly inconsistent. Furthermore, evaluations of the effects of GE at weaning in comparison to those of widely used therapeutic antibiotics have been scarce. To explore the mode of action of GE in selected tissues and plasma, we evaluated gut morphology, antioxidant and inflammation indices. Accordingly, 180 weaning piglets were allocated to three treatment groups: negative control (NC), NC and antibiotic treatment for the first 5 days of the trial (positive control, PC), and NC and GE (entire trial). The villus surface was positively affected by GE and PC on day 27/28 of the trial in the jejunum and on day 55/56 of the trial in the ileum. In the colon, NC tended (p < 0.10) to increase crypt parameters compared to PC on day 55/56. The PC group tended (p < 0.10) to increase catalase activity in the ileum and decrease Cu/Zn-SOD activity in the jejunum, both co...