Gastrointestinal Nematodes of Goats: Host-parasite Relationship Differences in Breeds at Summer Mountain Pasture in Northern Italy

Control of gastrointestinal helminths in small ruminants to prevent anthelmintic resistance: the Italian experience

Helminth infections are ubiquitous in grazing ruminants and cause significant costs due to production losses. Moreover, anthelmintic resistance (AR) in parasites is now widespread throughout Europe and poses a major threat to the sustainability of modern ruminant livestock farming. Epidemiological data on the prevalence and distribution of gastrointestinal nematodes, cestodes and liver- and rumen-flukes in Italian small ruminants are outdated and fragmentary. However, anthelmintics are commonly used to control these infections and often without prior diagnosis. Compared to other European countries, few reports of AR in small ruminants against levamisole, ivermectin and benzimidazoles have been published in Italy, but recent studies suggest that this phenomenon is spreading. Increased and integrated research efforts in developing innovative approaches to control helminth infections and AR are needed and must be tailored to the peculiarities of each context in order to be effectively implemented. This manuscript provides an overview on helminth prevalence and distribution, sustainable treatment strategies and integrated control approaches in small ruminants in Italy. The implementation of targeted treatments and targeted selective treatments is discussed based on different parameters, such as fecal egg count, degree of anaemia (FAMACHA© method), milk production and body condition score. In addition, several Italian studies have also investigated the implementation of alternative strategies such as the use of different natural bioactive compounds or genetic selection for resistance and resilience to helminth infections. These concrete solutions for helminth management in small ruminant farms in the country are reported and discussed, representing a valid example for other Mediterranean countries.

In Vitro Evaluations and Comparison of the Efficacy of Two Commercial Products Containing Condensed Tannins and of Saifoin (Onobrychis viciifolia Scop.) Hay against Gastrointestinal Nematodes of Goats

Gastrointestinal nematodes (GINs) is a limiting health factor for dairy goats, and the integration of the diet with fodder containing condensed tannins (CT) is becoming increasingly important to control GINs. To preliminary evaluate their potential role as part of GIN control in goat breeding, the in vitro anthelmintic efficacy of the CTs of Silvafeed BYPRO (SBP), Silvafeed Q powder (SQ), and sainfoin hay (SH) was evaluated, and the untargeted metabolomics profiling of the selected formulations was performed. CTs were extracted in water and in ethanol, their concentration was determined, and their chemical characterization was conducted using High-Performance Liquid Chromatography (HPLC) coupled to High-Resolution Mass Spectrometry (HRMS) platform. The in vitro anthelmintic activity of the extracts was evaluated using the Eggs Hatch Test (EHT) and the Larval Migration Inhibition Test (LMIT) using different extract concentrations (150, 300, 600, and 1200 μg/mL). The metabolomic profile of the ethanol extract showed a high number of flavonoids, while the water extract showed higher levels of hydrolysable tannins. The ethanol extracts were effective on both eggs hatching and larvae migration at low concentrations (150 μg/mL) for the three analyzed samples, while the water extracts showed more varied results: SH showed the greatest ovicidal efficacy (concentration 150 μg/mL, %IH = 40.9), while SBP and SQ were more effective against the larvae migration (concentration 600 μg/mL, %LMI = 69.7% and 88%), respectively. The integration of CT-rich fodder into the diet may be considered for the control of GIN infection in goats.

Comparison of Female Verzaschese and Camosciata delle Alpi Goats' Hematological Parameters in The Context of Adaptation to Local Environmental Conditions in Semi-Extensive Systems in Italy

Local livestock breeds are pivotal to ensure sustainable agriculture and represent a real genetic resource in the context of genetic variability reduction. This study aimed at broadening the knowledge about hematological values in female Verzaschese and Camosciata delle Alpi goats (an Italian local and a cosmopolitan goat breed, respectively) and investigating factors affecting them (i.e., breed, age, season). Blood samples were collected monthly from 34 Verzaschese and 37 Camosciata delle Alpi female goats kept under the same semi-extensive farming system for a whole year. The main hematological parameters were evaluated, and descriptive as well as inferential statistical analyses were performed. Reference intervals for complete blood cell count were established and several inter-breed differences were found. In particular, most of the red blood cell parameters were higher in Verzaschese than Camosciata delle Alpi (p < 0.05) suggesting a greater gastrointestinal parasites’ resilience of the local breed. The age effect (p < 0.05) was consistent with the literature while the season effect (p < 0.05) could be explained by the melatonin immunostimulant action and gastrointestinal parasitism influence. Overall, differences in blood values could be attributed to physiological changes and adaptive strategies developed through centuries highlighting the remarkable rusticity and adaptation to the environment and farming system of the local breed.

COMPARISON OF NATURALLY OCCURRING EIMERIA INFECTIONS IN ALPINE AND NERA DI VERZASCA GOAT BREEDS REARED IN A SUB-ALPINE ENVIRONMENT

The present study aimed to describe the natural trend of Eimeria spp. oocysts shedding in different breeds of adult goats raised in a sub-Alpine ecosystem by quantitative copromicroscopic analysis. A 1-yr long longitudinal study was planned in a goat herd composed of non-native (Alpine) and autochthonous (Nera di Verzasca) breeds. FLOTAC double technique was implemented to analyze individual fecal samples collected monthly from 2 groups (non-native and native) of 10 goats each. A generalized linear mixed model, in which each goat was included as a random intercept effect, identified 4 predictors of logarithmically transformed oocysts per gram shedding: the number of days from parturition (F = 27.744; P < 0.001), the interaction between the goat breed and the number of days from parturition (F = 8.407; P = 0.004), the interaction between the number of days from parturition and the number of parturitions (F = 6.371; P = 0.012), and the interaction between the monthly rainfalls and temperatures (F = 4.536; P = 0.023). These results indicate that the physiological status (number of days from parturition) of adult goats and its interaction with other individual features (number of parturitions and breed) can affect Eimeria spp. oocysts shedding. Besides, a combination of climatic variables can pose a risk for Eimeria spp. infection in goats reared in the sub-Alpine environment.