Assessing the impact of biosecurity practices and animal welfare in small-scale mountain dairy farming.

This study estimates the association between the level of biosecurity, animal welfare, milk quality, and economic performance on 2291 mountain dairy farms which largely differs in management and structure from large dairy operations in the lowlands mainly due to climatic and topographic constraints in mountain areas. The dairy industry's increasing emphasis on biosecurity is crucial for ensuring animal health, productivity, and disease mitigation. Therefore, in the present study the biosecurity and animal welfare status of mountain dairy farms were assessed considering the official welfare protocol for dairy cows of the Italian ClassyFarm system. Our findings reveal a suboptimal adoption of biosecurity measures, attributed to structural limitations in mountain farms and farmers' awareness gaps. Despite these challenges, the economic significance of biosecurity adoption is evident, emphasizing potential benefits for farm viability and animal health. Conversely, the study indicates a moderate to good welfare status in assessed farms, reflecting farmers' awareness of the importance of high welfare standards for dairy cows. Improved welfare positively correlates with milk sales and productivity, highlighting the economic advantages of prioritizing animal well-being. Challenges persist, particularly regarding animal housing deficiencies and related consumer concerns about animal welfare in dairy production. Therefore, targeted interventions and educational initiatives are crucial to empower farmers and promote best practices in biosecurity and animal welfare management. However, addressing resultant production cost increases necessitates society's willingness to pay more for animal-based food, emphasizing the importance of aligning economic incentives with sustainable farming practices.

Alpine grazing management, breed and diet effects on coagulation properties, composition, and microbiota of dairy cow milk by commercial mountain based herds.

Cow milk microbiota has received increased attention in recent years, not only because of its importance for human health but also because of its effect on the quality and technological properties of milk. Several studies, therefore, have investigated the effect of various production factors on the microbial composition of milk. However, most of the previous studies considered a limited number of animals from experimental or single farm, which could have biased the results. Therefore, this study aimed to understand the effect of different alpine production systems on the compositional and microbiological quality of milk, considering commercial herds with different feeding intensities and cattle breeds. The results obtained in this work indicated that the month/season of sampling (July for summer or February for winter) more than farm, breed and cow diet exerted significant effects on cow milk parameters and microbiota. In particular, significant differences were observed for urea content in milk between sampling seasons. Differences in milk fat were mainly related to breed specific effects. From a microbiological point of view, statistically significant differences were found in presumptive lactic acid bacteria counts. Based on a culture-independent method, milk obtained in February harbored the highest number of Firmicutes (e.g., Lactobacillus) and the lowest number of Actinobacteria (e.g., Corynebacterium). Moreover, bacterial richness and diversity were higher in July/summer during alpine pasture season indicating a significant effect of pasture feed on the growth of bacterial communities. The results of this study highlighted the effect of month/season mainly related to differences in feeding management (e.g., access to pasture during vegetation period, concentrates supplementation) on composition and microbiota in milk.

Exploring the heights: Impact of altitude on dairy milk composition.

The aim of the present study was to assess the impact of altitude on the quality of milk from dairy cows housed in small-scale farms in alpine areas. Therefore, a dataset comprising 5,680 bulk milk samples from 32 farms located at different geographical altitudes was considered. Milk traits such as fat, protein, lactose, free fatty acids, casein, milk urea nitrogen content, pH value, and somatic cell score were examined in the laboratories of the South Tyrolean Dairy Association using mid-infrared spectroscopy. The data were analyzed using a statistical model that considered altitude category, grazing practice, housing system, and season of milk analysis as fixed effects. The findings revealed a positive association between altitude and milk fat, free fatty acids, and somatic cell count. Conversely, lactose content, milk urea nitrogen, and pH value in milk from cows kept on farms at higher altitude (>1,200 m above sea level) showed a negative relationship with altitude. Farms located at altitudes above 1,200 m exhibited higher fat, protein, urea, and somatic cell content than farms located at lower levels. The results provide new insights into a production effect that has so far received little attention and should be considered in farm management (e.g., feeding management, breed decision) to ensure animal health and the associated animal welfare as well as the productivity of dairy cows reared in traditional small-scale mountain dairy farms.

Effect of slaughter age on environmental efficiency on beef cattle in marginal area including soil carbon sequestration: A case of study in Italian Alpine area.

The production of beef carries significant environmental repercussions on a worldwide level. Considering that the production of beef in Alpine mountainous regions, such as South Tyrol (Italy), constitutes a modest yet progressively growing segment within the local agricultural sector focus must be put on minimizing the environmental impact of producing one kilogram of meat, while also accounting for the carbon sequestered by Alpine pastures in such marginal areas. To this end 20 beef farms distributed in the South Tyrolean region (Italy) were divided based on the age at slaughter of the beef cattle: 10 farms with a slaughter age of 12 months (SA12) and 10 farms with a slaughter age of 24 months (SA24). Live cycle assessment (LCA) approach was used, and the impact was estimated using two functional units (FU): 1 kg of live weight (LW) and 1 kg of carcass weight (CW). Global warming potential (GWP100, kg CO2-eq), acidification potential (AP, g SO2-eq), and eutrophication potential (EP, g PO4-eq) were investigated. Furthermore, within the account, the carbon sequestered by pastures and permanent grassland has been included for estimated the overall carbon footprint. In terms of GWP100, the SA12 system proved to be significantly lower for both two functional units under studies, with reductions of 8.5 % and 7.4 % in terms of LW and CW, respectively, compared to the SA24 system, specifically, the SA12 system showed an environmental impact in terms of GWP100 of 19.5 ± 1.1 kg CO2-eq/kg LW, which was significantly lower than the SA24 system that exhibited a value of 22.9 ± 1.1 kg CO2-eq/kg LW (P < 0.05). When accounting for the carbon sequestered within the system, the observed values in terms of GWP100 are significantly lower for SA12 compared to SA24, 17.6 ± 1.5 vs. 20.9 ± 1.5 kg CO2-eq/Kg LW (P < 0.05), and 29.2 ± 2.5 vs. 38.7 ± 2.5 kg CO2-eq/Kg CW (P < 0.01). These differences are due to less purchase of concentrated feed and greater use of natural resources such as pastures and permanent grasslands. The research indicated that the production of beef in the Alpine region of South Tyrol predominantly occurs within extensive parameters, leading to a satisfactory environmental profile, also including the C sequestration.

Assessment of the chemical and genetic variability among accessions of Cicerbita alpina (L.) Wallr., an alpine plant with anthelmintic properties.

Cicerbita alpina (L.) Wallr, is a perennial alpine plant and a member of the Asteraceae family, typically found at altitudes above 1000 meters in the Italian Alps. Although previously utilized primarily as a local delicacy, recent studies have revealed strong antiparasitic activity through in vitro experiments. In Europe, numerous chemical drugs employed to combat nematodes - helminths that infest the digestive tract of livestock - are banned due to their environmental harm or show only reduced efficiency because of the development of resistance. Consequently, there is a growing demand for new alternative anthelmintic treatments in agricultural practices. Specialized metabolites found in the extracts of C. alpina could offer a sustainable and biological alternative to chemical drugs, specifically for nematode control. For this purpose, a unique germplasm collection originating from eight distinct natural populations in the Italian Alps was analyzed for its chemical diversity using state-of-the-art targeted LC-MS/MS spectrometry, including quantification based on multiple reaction monitoring. The predominant metabolites identified from the species were the caffeic acid derivatives chicoric acid, chlorogenic acid, and 3. 5-dicaffeoylquinic acid, the sesquiterpene lactone derivative 8-O-acetyl-15-ß-D-glucopyranosyl lactucin and the flavone glycosides, apigenin-7-O-glucoside and luteolin-7-O-glucoside, alongside their precursors apigenin and luteolin, respectively. Additionally, the genetic diversity of eighty individual plants within the germplasm collection was evaluated using ten DNA molecular markers (Simple Sequence Repeats), successfully transferred from two closely related species (Cichorium intybus and Tanacetum parthenium). This investigation unveiled a significant range of genetic diversity within the examined populations, resulting in the establishment of three distinct genetic groups. The findings were further correlated with the original ecological environment and local climate conditions spanning a biennial period, indicating substantial variations among the different accessions and the intricate interplay between genetic background and environmental factors. These results could serve as a basis for future domestication of the species through plant breeding programs ensuring product quality, but also facilitating the cultivation of C. alpina in more diverse geographic regions.

Associated risk factors for skin alterations in dairy cattle kept on small scale mountain farms.

The objective of this study was to determine the risk factors for skin alterations at herd and cow level on dairy farms with different housing systems in South Tyrol (Northern Italy). A cross-sectional study was conducted on 204 farms (111 free stalls and 93 tie stalls) from March to October 2019 assessing the level of animal welfare using resource-based and animal-based indicators. A total number of 1,891 dairy cows were evaluated, of which 43.5% were reared in tie stalls and 56.5% in free stalls. A logistic regression model identified the herd and cow level risks factors for neck and leg skin alterations in the two different systems. There was a higher prevalence for skin lesions on the neck (Odd Ratio (OR) = 2.36) and hock (OR = 2.82) for tie stalls. Irrespective of the housing system the soft-based stall mattresses had a lower prevalence for knee and hock lesions of 0.48 and 0.54, respectively, compared to wood base stalls for both knee (OR = 2.19) and hock (OR = 2.47) consecutively. The prevalence of skin alterations on the knee (OR = 0.42) and hock (OR = 0.33) decreased by the presence of sawdust as bedding material. Similarly, straw (OR = 0.61) and lime-straw-water bedding (OR = 0.59) reduced the prevalence for skin alterations on the hock. Access to pasture reduced the prevalence of skin alterations on the neck (OR = 0.34), the knee (OR = 0.77), and on the hock (OR = 0.46) regardless of the housing system. In conclusion, the assessment of risk factors of different skin alterations in different housing systems can contribute to the improvement of overall animal welfare in traditional small scale mountain dairy systems.

Ascaridia galli - An old problem that requires new solutions.

Reports of Ascaridia galli in laying hens in Europe have increased since the ban on conventional battery cages in 2012. As this parasite is transmitted directly via the faecal-oral route by parasite eggs containing a larva, it is reasonable to assume that the escalating problem is related to the increased exposure now occurring in modern welfare-friendly cage-free housing systems. On many farms, A. galli reappears in subsequent flocks, even though the birds have no access to the outdoors, biosecurity is high and empty houses are cleaned and disinfected during downtime. Since the egg production cycle lasts only ≈80 weeks and recombinant antigen production for helminth vaccines has not yet been solved, the development of a vaccine seems to be an unrealistic option. Therefore, disrupting the life cycle of the parasite by other means, including the strategic use of dewormers, appears to be the key to controlling infection. Of concern is that only one class of anthelmintics is licenced for poultry in Europe and that are usually administered indiscriminately through the birds' drinking water and often too late when the parasite is already established. If current calendar-based parasite control strategies are not changed, there is a risk that resistance to anthelmintics may develop, as has already been demonstrated with nematodes in livestock. We insist that treatments can be more effective and the risk of developing drug resistance can be mitigated if we invest in a better understanding of A. galli responses to more prudent and judicious use of anthelmintics. This review identifies knowledge gaps and highlights aspects of sustainable parasite control that require further research to support commercial egg producers.

Pattern and repeatability of ascarid-specific antigen excretion through chicken faeces, and the diagnostic accuracy of coproantigen measurements as compared with McMaster egg counts and plasma and egg yolk antibody measurements in laying hens.

BACKGROUND: A coproantigen enzyme-linked immunosorbent assay (ELISA) has recently been proposed for detecting ascarid infections in chickens. The excretion pattern of ascarid antigens through chicken faeces and the consistency of measurements over the course of infections are currently unknown. This study evaluates the pattern and repeatability of worm antigen per gram of faeces (APG) and compares the diagnostic performance of the coproantigen ELISA with a plasma and egg yolk antibody ELISA and McMaster faecal egg counts (M-FEC) at different weeks post-infection (wpi). METHODS: Faecal, blood and egg yolk samples were collected from laying hens that were orally infected with a mix of Ascaridia galli and Heterakis gallinarum eggs (N = 108) or kept as uninfected controls (N = 71). Measurements including (a) APG using a coproantigen ELISA, (b) eggs per gram of faeces (EPG) using the McMaster technique and (c) ascarid-specific IgY in plasma and in egg yolks using an ascarid-specific antibody ELISA) were performed between wpi 2 and 18. RESULTS: Time-dependent significant differences in APG between infected and non-infected laying hens were quantified. At wpi 2 (t(164) = 0.66, P = 1.00) and 4 (t(164) = -3.09, P = 0.094) no significant differences were observed between the groups, whereas infected hens had significantly higher levels of APG than controls by wpi 6 (t(164) = -6.74, P < 0.001). As indicated by a high overall repeatability estimate of 0.91 (CI = 0.89-0.93), APG could be measured consistently from the same individual. Compared to McMaster and antibody ELISA, coproantigen ELISA showed the highest overall diagnostic performance (area under curve, AUC = 0.93), although the differences were time-dependent. From wpi 6 to 18 coproantigen ELISA had an AUC > 0.95, while plasma IgY ELISA showed the highest diagnostic performance in wpi 2 (AUC = 0.95). M-FEC had the highest correlation with total worm burden, while APG had highest correlations with weights and lengths of A. galli. CONCLUSION: Ascarid antigen excretion through chicken faeces can be measured with high accuracy and repeatability using a coproantigen ELISA. The antigen excretion increases over time, and is associated with worm maturation, particularly with the size of A. galli. Our results suggest the necessity of complementary use of different diagnostic tools for a more accurate diagnosis of infections.

Quantifying methane emissions under field conditions under 2 different dairy production scenarios: Low-input versus high-input milk production.

Livestock production systems with ruminants play a relevant role in the emission of the greenhouse gas CH4, which is known to significantly contribute to global warming. Consequently, it is a major societal concern to develop strategies in mitigating such emissions. In addition to breeding toward low-emitting cows, management strategies could also help in reducing greenhouse gas emissions from dairy farms. However, information is required for appropriate decision making. To the best of our knowledge, this is the first study that considers different, already available equations to estimate CH4 emissions of small-scale dairy farms in the mountain region, which largely differ from large dairy farms in the lowlands concerning management and production. For this study, 2 different production systems, both typical for small-scale dairy farming in mountain regions, were simultaneously run over 3 yr at an experimental farm as follows: (1) a high-input production system, characterized by intensive feeding with high amounts of external concentrates and maize silage, year-round housing, and high yielding Simmental cattle breed, and (2) a low-input production system, characterized by prevailing hay and pasture feeding and silage ban, thus covering most of the energy requirements by forage harvested on-farm and the use of the local Tyrolean Grey cattle breed. Results reveal that feeding management has a significant effect on the amount of CH4 emissions. The low-input production system produced less CH4 per cow and per day compared with the high-input production system. However, if calculated per kilogram of milk, the high-input scenario produced proportionally less CH4 than the low-input one. Findings of this study highlight the potential to assess in a fast and cost-effective way the CH4 emission in different dairy production systems. This information contributes to the debate about the future of sustainable milk production in mountain regions, where the production of feed resources is climatically constrained, and could be useful for breeding purposes toward lower CH4-emissions.

In vitro evaluation of the effects of methanolic plant extracts on the embryonation rate of Ascaridia galli eggs.

The present study aims to find efficient alternatives to synthetic anthelmintics among ethno-veterinary herbs. Ascaridia galli eggs isolated from the worm uterus were exposed in vitro to methanolic extracts (ME) of nine plant species such as Achillea millefolium (AM), Artemisia absinthium (AA), Artemisia vulgaris (AV), Cicerbita alpina (CA), Cichorium intybus (CI), Inula helenium (IH), Origanum vulgare (OV), Tanacetum vulgare (TV), Tanacetum parthenium (TP). Flubendazole (FL), 0.5% formalin with dimethylsulfoxide and Petri dishes without the addition of reagents were used as positive, negative and untreated control respectively. The effects of the different ME at concentrations 0.500, 0.325, 0.200 mg/ml were assessed on the embryonic development (ED) of the eggs in duplicate. Logit analysis was used to calculate EC50 values. A generalized linear mixed model, having plant species and concentration as fixed effect and day as repeated measure, was used to determine differences in ED. Estimated EC50 was the lowest for FL at 0.11 mg/ml. CA and TV followed with 0.27 mg/ml and 0.32 mg/ml. ED for FL was significantly lower (25%) than that of CA (47%). The analysis showed 0.5 mg/ml of the ME of CA and TV significantly affected the ED at 35% and 42% inhibitions respectively. The ED for all ME showed similar pattern i.e., relatively higher efficacy in the first experimental week compared to the rest of the experimental period. The effect from all multicomponent extracts is time and dose dependent. The plants have promising results in inhibiting ED, contributing to the identification of alternative anthelmintic treatments.

A copro-antigen ELISA for the detection of ascarid infections in chickens.

A reliable method of diagnosing the most prevalent helminth infections in chickens is vital for developing effective control strategies. Ascaridia galli and Heterakisgallinarum are phylogenetically close nematode species that can elicit the development of cross-reactive antibodies in chickens. Therefore, an enzyme-linked immunoassay (ELISA) based on Ascaridia galli antigens in faeces of chickens to detect and quantify infections with both A. galli and H. gallinarum was developed. The ELISA utilised polyclonal antibodies that were obtained from rabbits immunised with soluble antigens isolated from A. galli. In two separate experiments, chickens were kept as uninfected controls or were orally infected with either 100 or 1000 of embryonated eggs of A. galli or H.gallinarum. Faecal samples were collected after 28-30 weeks post-infection. The ELISA was then used to quantify the concentration of soluble worm antigens in faecal samples, i.e., the amount of antigen per gram faeces, APG. The APG from infected chickens was significantly higher than non-infected groups in both experiments (P 0.001). Both 100 and 1000 infection dose groups were not significantly different (P = 0.999) in the experiment with H. gallinarum, whereas in the experiment with A. galli, APG was significantly higher in the 1000 infection group (P 0.001). A receiver operation characteristics (ROC) analysis that evaluates the qualitative performance of diagnostics tests was used to calculate the assay parameters within each mono-infection experiment. The result showed that the assay had a high diagnostics accuracy with an area-under-curve (AUC) of 0.99 in detecting infection in A. galli infected chickens and a moderate-high accuracy (AUC = 0.89) in birds infected with H. gallinarum. The diagnostic sensitivity and specificity of the assay at the optimal cut-off point equivalent to Youden index were 93% and 100% for detecting infections in A. galli experiment and 85% and 92% in H. gallinarum experiment, respectively. The correlation between faecal antigen concentration and all worm burden parameters was positive but generally low (r < 0.33), which provided less information about infection intensities. Nonetheless, these results indicate that a reliable and accurate qualitative diagnosis of the two most prevalent intestinal nematodes in chickens can be achieved using a non-invasive copro-antigen ELISA assay.

Effects of Housing and Management Factors on Selected Indicators of the Welfare Quality® Protocol in Loose-Housed Dairy Cows.

The objective of this study was to examine the effects of housing and management factors on animal welfare indicators in dairy cows using a benchmarking approach. In total, 63 conventional dairy cattle farms with zero-grazing in Northern Germany were assessed using selected animal welfare indicators (body condition score, integument alterations, lameness, milk somatic cell count, and social behaviour) of the Welfare Quality® protocol. Additionally, housing characteristics such as designs of barns, cubicles, and floors were documented during farm visits and farmers were interviewed concerning their common management routines. Farms were categorized into a high welfare or low welfare group by calculating upper and lower tertiles for each of the animal welfare indicators separately. Both groups were compared regarding housing conditions and management practices using univariable and multivariable logistic regressions. Several associations between housing and management factors and animal welfare indicators were demonstrated in univariable analysis (p < 0.20). Significant effects within multivariable logistic regression analysis were determined for lameness (routine use of foot-baths), milk somatic cell count (milking frequency) and social behaviour (cow-to-stall ratio) (p < 0.05). Comparing farms with higher and lower animal welfare status can provide useful information about effective options to improve animal welfare.

Effects of Different Housing Systems during Suckling and Rearing Period on Skin and Tail Lesions, Tail Losses and Performance of Growing and Finishing Pigs.

Feasible alternatives to stressful weaning and tail-docking are needed to inhibit tail biting. Therefore, we investigated the effects of housing systems for 1106 pigs that were weaned from: (1) conventional farrowing crates (FC), (2) free-farrowing pens (FF), or (3) group housing of lactating sows (GH) into (1) conventional rearing pens (Conv) or (2) piglets remained in their farrowing pens for rearing (Reaf). Tails were docked or left undocked batchwise. All pigs were regrouped for the fattening period. Pigs were scored for skin lesions, tail lesions and losses. After weaning, Conv-GH pigs had significantly less skin lesions than Conv-FC and Conv-FF pigs. After regrouping for fattening, Reaf-GH pigs had significantly less skin lesions than Conv pigs, Reaf-FC and Reaf-FF. The frequency of tail lesions of undocked Conv pigs peaked in week 4 (66.8%). Two weeks later, Reaf undocked pigs reached their maximum (36.2%). At the end of fattening, 99.3% of undocked Conv pigs and 43.1% of undocked Reaf pigs lost parts of their tail. In conclusion, the co-mingling of piglets during suckling reduced the incidence of skin lesions. Rearing in the farrowing pen significantly reduced the incidence of tail lesions and losses for undocked pigs. No housing system negatively affected the performance.

Effect of low and high concentrate supplementation on health and welfare indicators in different breeds in small-scale mountain dairy farms.

We investigated and compared the effects of low and high concentrate supplementation in terms of animal welfare, health and reproductive performance in two different dairy cow breeds on small-scale mountain farms. 64 South Tyrolean dairy farms were evaluated using an on-farm assessment for animal-based and resource-based welfare indicators, data from test day records, and a questionnaire for the farmer. Farms were divided into four groups: low input Tyrolean Grey (L-TG), low input Brown Swiss (L-BS), high input Tyrolean Grey (H-TG) and high input Brown Swiss (H-BS). Effects of intensity level, breed and their interaction were calculated and analyzed statistically. The predominant husbandry system across all groups was tie-stall. The average energy-corrected milk yield increased with increasing concentrate level, with L-TG showing the lowest and H-BS showing the highest milk yield. Age at first calving was lowest in H-BS when compared to all other systems, while numbers of lactations were higher in L-TG compared to H-BS. Feed efficiency (percentage of milk out of roughage) was significantly higher in L-TG and L-BS when compared to H-TG and H-BS. L-BS showed the poorest results for most of the welfare indicators such as lean cows, lesions and percentage of dirty animals. In conclusion, a higher concentrate level in diets does not lead automatically to lower animal welfare for dairy cows in alpine regions. Indeed, keeping high yielding breeds in extensive systems seems to be challenging. The dual-purpose breed TG showed some clear advantages in that calving interval was lower and the number of lactations greater.

Impact of Nematode Infections on Non-specific and Vaccine-Induced Humoral Immunity in Dual-Purpose or Layer-Type Chicken Genotypes.

Nematode infections may induce immune-modulatory effects and influence host-immune responses to other pathogens. The aim of the study was to investigate whether a mixed nematode-infection influences non-specific and vaccine-induced humoral immunity against Newcastle Disease Virus (NDV), Infectious Bronchitis Virus (IBV), and Avian Metapneumovirus (AMPV) in already vaccinated hens of a dual-purpose (Lohmann Dual, LD) or a layer genotype (Lohmann Brown Plus; LB). Until 17 weeks-of-age, LD (n = 70) and LB (n = 109) hens were vaccinated against major bacterial and viral diseases and coccidiosis. At 24 weeks-of-age, the hens received either a placebo or an oral inoculation of 1,000 infectious eggs of A. galli and H. gallinarum. Plasma total immunoglobulin (Ig) isotypes (IgY, IgM, IgA) levels and vaccine-induced antibody titers against NDV, IBV, and AMPV were determined from 2 to 18 weeks post-infection (wpi). Infections had no suppressing effect on total Ig isotypes IgY, IgM, and IgA as well as on vaccine-induced antibody titers against NDV, IBV, and AMPV (P > 0.05). Overall, LB hens had higher levels of IgY, IgM, and IgA than those of LD hens (P < 0.05). There were no differences between IBV titers of the two genotypes (P > 0.05). Independent of infection status of the hens, NDV titers were higher in LB hens than in LD hens at wpi 2 (P < 0.05), but not in following weeks (P > 0.05). Uninfected LD hens had lower AMPV titers than their infected counterparts at 6 and 14 wpi (P < 0.05). Regardless of nematode infection, LD hens revealed a higher risk of responding weak to vaccination against NDV (odds ratio = 5.45; P = 0.021) and AMPV (odds ratio = 13.99, P < 0.001) than did LB hens (P > 0.05). We conclude that nematode infections have no adverse effects on non-specific and vaccine-induced humoral immunity in either genotype. LB hens have higher levels of total immunoglobulin isotypes than LD hens. Except for IBV, vaccine-induced humoral immune responses show a dependency on genotype. Dual-purpose hens show lower responsiveness to vaccinations against NDV and AMPV, possibly due to factors associated with increased body fat reserves in this genotype.

Environmental and biodiversity effects of different beef production systems.

Agricultural livestock production ranks among the most environmental impactful industry sectors at the global level, and within the livestock sector, beef production accounts for a large proportion of environmental damage. Beef production in Alpine mountain regions, such as in South Tyrol (Italy), is a small, but increasing agricultural sector. Thus, the aim of this study was to examine the environmental impact of different organic and conventional beef production systems in South Tyrol and to compare their environmental impact and effect on biodiversity under Alpine production conditions. Live cycle assessment (LCA) approach was used and 1 kg of live weight (LW) was chosen as functional unit (FU). Global warming potential (GWP, kg CO2-eq), acidification potential (AP, g SO2-eq), eutrophication potential (EP, g PO4-eq), non-renewable energy use (NRE, MJ-eq), land occupation (LO, m2 organic land/year) and biodiversity damage potential (BDP) expressed in potential disappeared fraction (PDF) were investigated. The study involved 18 beef cattle farms in the South Tyrolean region: Conventional calf-fattening farms (CCF = 6), organic suckler cow farms (SCF = 6), and conventional heifer/ox fattening farms (HOF = 6). The CCF system showed a higher environmental impact compared to SCF and HOF systems for all impact categories (P < 0.05). Between the organic and the conventional system (SCF and HOF), no significant differences (P > 0.05) were found for most of the considered impact categories (means ± SEM per FU): GWP: 19.8 vs 17.1 ± 4.2 kg CO2-eq, AP: 11.4 vs 9.3 ± 4.7 g SO2-eq, EP: 4.1 vs 2.8 ± 1.2, NRE: 21.9 vs 13.8 ± 7 MJ-eq, SCF and HOF respectively. Only for LO (70.8 vs 44.1 ± 17.7 m2 organic/y, P < 0.01, SCF and HOF respectively) and the effect on BDP (-1.93 vs -0.85 ± 0.35, PDF, P < 0.01, SCF and HOF respectively) differences between organic and conventional production methods could be revealed. The study showed that beef cattle husbandry in the Alpine area has a satisfactory environmental performance. In particular, the systems studied showed a positive impact in terms of biodiversity.

Anthelmintic resistance in gastrointestinal nematodes in sheep raised under mountain farming conditions in Northern Italy.

Anthelmintic resistance (AR) in sheep raised under mountain farming conditions in South Tyrol (Northern Italy) was assessed on eight farms (n=99 animals). A faecal egg count reduction (FECR) test was done after routine anthelmintic treatments. Furthermore, on 27 farms (n=306 animals), a FECR test was conducted after oral formulations of a macrocyclic lactone (ML), benzimidazole (BZ) (partly in combination with salicylanilide (SA)) or a combination of imidazothiazole and SA were applied under controlled conditions on the same farm. Following routine treatments, three of five ML-treated flocks showed an adequate efficacy, while the other two reached a FECR of only around 75 per cent. A wide range of gastrointestinal nematode genera were identified in one flock following the treatment. From the three BZ-treated flocks, only one showed an adequate FECR, both other farms reached 68 per cent and 84 per cent, respectively. Under controlled conditions, FECR ranged between 77 per cent and 81 per cent indicating AR for all the applied anthelmintics. Trichostrongylus species, Teladorsagia species and Haemonchus species were identified after ML treatment, Teladorsagia species after BZ treatment and Trichostrongylus species and Haemonchus species after combined BZ and SA application. Taking into consideration that underdosing might have affected results of the routine treatments, a high prevalence of AR was found in sheep under mountain farming conditions.

Resistance and tolerance to mixed nematode infections in relation to performance level in laying hens.

Modern chickens have been genetically developed to perform high under optimal conditions. We hypothesized that high-performance is associated with a higher sensitivity to environmental challenges in laying hens. By using nematode infections as an environmental stressor, we assessed performance-level associated host responses in a high (i.e. Lohmann Brown Plus, LB) and in a lower performing, a so-called dual-purpose chicken genotype (i.e. Lohmann Dual, LD). The hens were infected with 1000 eggs of Ascaridia galli and Heterakis gallinarum at 24 weeks of age. Hen performance parameters, humoral immune responses in plasma and egg yolks and worm burdens were assessed at several occasions over a period of 18 weeks post infection (wpi). While infections had no significant effect on feed intake (P = 0.130) and body weight in both genotypes (P = 0.392), feed conversion efficiency was negatively affected by infections (P = 0.017). Infections reduced both laying rate and egg weight and thereby per capita egg mass in both genotypes (P < 0.05). While laying rate in infected LB hens decreased significantly (P < 0.05) in the early infection period (i.e. by 3 wpi), the decrease in LD hens appeared much later (i.e. by 14 wpi). Worm burdens resulting from the experimental infection were not different between the genotypes for both worm species (P > 0.05), whereas LB hens were more susceptible (P < 0.05) to re-infections than LD hens. Changes in humoral immune responses (i.e. ascarid-specific IgY antibodies in plasma and egg yolks) of the two genotypes over time reflected closely the corresponding changes in larval counts of the hens, descending from both experimental and subsequent natural infections in both genotypes. Infections caused a shift in egg size classes, leading to smaller frequency of larger eggs in both genotypes. Infections reduced egg weight (P = 0.018) and led to a reduced fat content in the egg yolks (P = 0.045). The proportion of poly-unsaturated fatty acids (PUFA), especially n-6-PUFA, was also lower in egg yolks of the infected hens (P = 0.032). We conclude that tolerance to nematode infections in laying hens is dependent on host-performance level. The impairment in host tolerance was both genotype and time dependent, likely due to differences in genetic programming for production peak and persistency of the two genotypes. The two genotypes exhibited similar levels of resistance after a fully controlled experimental infection, but the high performing hens were more susceptible to subsequent natural infections. Infections negatively affected economically important egg-quality traits, including egg weight, fat content and fatty acid profiles in egg yolks.

Resistance and tolerance to mixed nematode infections in chicken genotypes with extremely different growth rates.

Fast growing broilers are less able to cope with fitness related challenges. As the allocation of metabolic resources may be traded off between performance and defence functions in parasitized hosts, we hypothesized that fast growing broilers are more sensitive to mixed nematode infections compared with slower growing genotypes under the same environmental conditions. Therefore, we compared male birds of genotypes selected for either meat production (Ross-308, R) or egg production (Lohmann Brown Plus, LB) or for both purposes (Lohmann Dual, LD), to assess their resistance and tolerance to mixed nematode infections with Ascaridia galli and Heterakis gallinarum. While infections reduced feed intake in all three genotypes, feed conversion efficiency was not affected. Infections impaired growth performance only in R birds, indicating lower tolerance in the fast growing genotype compared with slower growing LB and LD genotypes. Impaired tolerance in R birds was associated with a relative nutrient scarcity due to an infection-induced lower feed intake. Resistance to experimentally induced infections depended on host genotype as well as on the worm species involved. Overall, the A. galli burden was higher in R than LB, whereas the burden of LD was not different from that of R and LB. In contrast, the H. gallinarum burden of first generation worms was similar in the three genotypes. Susceptibility to re-infection with H. gallinarum was higher in LB than in LD, whereas very low levels of re-infection were observed in R birds. Our data collectively suggest that resistance and tolerance to mixed nematode infections are sensitive to growth rate in chickens. These differences amongst genotypes may partly be associated with a mismatch between the actual nutrient supply and genotype-specific nutrient requirements.

Foot Pad Health as Part of On-Farm-Monitoring in Turkey Flocks.

Currently, there is no consistent approach to on-farm and post-mortem foot pad (FP) assessment in turkey husbandry in sampling of both feet, sample sizes of birds and scoring schemes during the production period. Therefore, in a field study, 11,400 turkeys, i.e., 22,800 feet, were macroscopically scored at 4-week intervals, 60 birds per flock per date, in accordance with the scale system of Hocking et al. (1). Spearman's rho was calculated between the foot pad dermatitis (FPD) score of both feet of an individual turkey. Sample size for FPD monitoring was calculated for several flock sizes, considering expected FPD prevalence and the error and confidence level (α = 0.01, 0.05, 0.1). To compare macroscopic to histological findings, ten excised FPs were histopathologically investigated by hematoxylin & eosin staining. To align manual macroscopic FPD evaluations with a technical system, 20 photographic images of FPD were measured using the ImageJ program. The scores of both feet of an individual turkey correlated between r = 0.252 and r = 1.000. Thus, both feet of a bird should be monitored, while the worse foot should be evaluated. As an exemplary sample size for on-farm FPD assessment, 77 turkey poults were calculated in a flock of 4,000 birds with an expected FPD prevalence of 40% and α = 0.1. The sample size of monitored birds within a flock should differ and depend on flock size and expected FPD prevalence. Histopathological findings showed normal and non-affected structures of a macroscopic Score 0 and a moderate ulcer of the macroscopic Score 1 and Score 2. The applied assessment scheme should distinguish first alterations and scar tissue as separate scores to differentiate the need for management intervention vs. the success of management measures that were already implemented. FPD affected areas were given lower Scores and assessed to be healthier when evaluated by an image system, compared to a manual assessment. Furthermore, with regard to an increase in camera-based assessments, the boundary of the metatarsal pad needs to be clarified. In conclusion, a new scoring system is required, as the size of the FP cannot be clearly defined and different tissue textures, as well as valid sample sizes are not currently sufficiently considered.