Evaluation of Inter-Observer Reliability of Animal Welfare Indicators: Which Is the Best Index to Use?

This study focuses on the problem of assessing inter-observer reliability (IOR) in the case of dichotomous categorical animal-based welfare indicators and the presence of two observers. Based on observations obtained from Animal Welfare Indicators (AWIN) project surveys conducted on nine dairy goat farms, and using udder asymmetry as an indicator, we compared the performance of the most popular agreement indexes available in the literature: Scott's π, Cohen's k, kPABAK, Holsti's H, Krippendorff's α, Hubert's Γ, Janson and Vegelius' J, Bangdiwala's B, Andrés and Marzo's ∆, and Gwet's γ(AC1). Confidence intervals were calculated using closed formulas of variance estimates for π, k, kPABAK, H, α, Γ, J, ∆, and γ(AC1), while the bootstrap and exact bootstrap methods were used for all the indexes. All the indexes and closed formulas of variance estimates were calculated using Microsoft Excel. The bootstrap method was performed with R software, while the exact bootstrap method was performed with SAS software. k, π, and α exhibited a paradoxical behavior, showing unacceptably low values even in the presence of very high concordance rates. B and γ(AC1) showed values very close to the concordance rate, independently of its value. Both bootstrap and exact bootstrap methods turned out to be simpler compared to the implementation of closed variance formulas and provided effective confidence intervals for all the considered indexes. The best approach for measuring IOR in these cases is the use of B or γ(AC1), with bootstrap or exact bootstrap methods for confidence interval calculation.

Sustainability of Four Dairy Farming Scenarios in an Alpine Environment: The Case Study of Toma di Lanzo Cheese.

The dairy sector accounts for a large share of all European agricultural production, at the same time however, it is one of the most ascribed sector contributors to the environmental impact of agriculture, particularly for greenhouse gas emissions. Simultaneously, it is a strategic sector for the economy but generates increasing debate in the community regarding the social aspects mainly related to the use of resources and the food-feed competition of livestock involving the reduction of human-edible crops. In this general framework, this study aims to compare four different dairy farming scenarios characterized by different use of environmental resources in the Alpine area, considering as a case study the production of the Toma di Lanzo cheese (a traditional cheese produced in the mountainous regions of Piedmont-Northwest Italy). The study envisaged the integrated use of three methodologies: Life Cycle Assessment, Life Cycle Costing and the assessment of human-edible feed conversion efficiency to jointly analyze environmental, economic and social aspects. The main results of this research highlighted how the utilization of local breeds, which maximize the efficiency in the use of territory resources, such as grasslands in a mountain environment, allowed dairy production to reduce emissions, when compared to the high-input traditional breeding systems. Although the mountain livestock systems have several critical issues mainly linked to social factors such as low generational turnover, work schedules, modest life quality of families, it is however possible to earn more income than in lowland scenarios. At the same time, this production system allows the Toma di Lanzo cheese-making heritage to be preserved. This mountain pasture cheese, to which superior organoleptic and nutritional characteristics are attributable, when compared to cheeses from the valley floor, incorporates traditional values, a link to the territory and the transmission of knowledge. With reference to food-feed competition in livestock involving the reduction of the use of human-edible crops and feedstuffs in animal diets, we found that grazing and grass-based feeding systems were one of the most sustainable ways to produce milk.

Effect of ruminally unprotected Echium oil on milk yield, composition and fatty acid profile in mid-lactation goats.

This study investigated the effects on goat milk yield and composition of a diet supplemented with Echium plantagineum oil (EPO). Twenty-four mid-lactation multiparous Camosciata goats were divided into two balanced groups and fed for 44 d a diet based on hay and concentrate, supplemented (EPO group, Echium) or not (CON group, control) with 40 ml of ruminally unprotected EPO. Individual milk yield was recorded and individual milk samples were collected at 11, 22, 33, and 44 d after supplementation. Milk samples were analysed for milk components and fatty acids (FA). Data were statistically analysed by repeated-measures analysis of variance. Milk yield, protein and lactose contents were significantly higher in EPO than CON group. The inclusion of EPO significantly decreased total saturated FA and total branched-chain FA, and contemporarily sharply increased trans biohydrogenation intermediates (P ⩽ 0.001). Milk concentration of α-linolenic, stearidonic and γ-linolenic acids increased by 23, 1000 and 67%, respectively (P ⩽ 0.001). Due to extensive ruminal biohydrogenation, their apparent transfer rate was less than 3%. As a consequence, the milk concentrations of very long-chain (VLC) polyunsaturated fatty acids (PUFA), such as eicosapentaenoic (20:5 n-3) and dihomo-γ-linolenic (20:3 n-6) acids, significantly increased with EPO treatment, but values remained very low. Docosahexaenoic acid (22:6 n-3) was undetectable in all analysed milk samples. Results show that ruminally unprotected EPO can enhance milk yield and protein and improve the overall goat milk FA profile. However, this kind of supplementation cannot be considered a valuable strategy to develop goat functional dairy products enriched with VLC n-3 PUFA for human consumption.

Milk yield, gross composition and fatty acid profile of dual-purpose Aosta Red Pied cows fed separate concentrate-forage versus total mixed ration.

This study was designed to evaluate the effects of two feeding methods on milk yield, composition and fatty acid (FA) profile obtained from dual-purpose cattle. Twenty-four Aosta Red Pied cows beyond peak of lactation were assigned to two groups and fed hay and concentrates in the proportions 0.69 and 0.31 on a dry matter basis for 10 weeks. Concentrates were offered separately from forages 6 times a day (separate ration, SR) or as a total mixed ration (TMR). The feeding method did not significantly influence dry matter intake (16.8 vs. 16.9 kg/head/day for SR- and TMR-fed cows, respectively), milk yield (17.4 vs. 17.5 kg/head/day), milk fat, protein and lactose contents (36.4 vs. 35.2, 33.5 vs. 32.8, and 47.3 vs. 47.4 g/kg) and yields (607.9 vs. 613.4, 567.4 vs. 572.7 and 805.5 vs. 829.7 g/head/day). The overall milk FA profile was very similar between groups. Milk concentrations of FA used as indirect markers of rumen function (C18:2 t10c12, odd- and branched-chain FA) and the extent of ruminal biohydrogenation were comparable (P > 0.05) between SR- and TMR-fed cows, suggesting that ruminal pH did not vary considerably as a consequence of the feeding strategy applied.