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Ortíz-Domínguez GA, González-Pech PG, Torres-Acosta JFDJ, Ventura-Cordero J, Villalba J, Sandoval-Castro CA. Relevance of Individual Data When Assessing the Gastrointestinal Nematode Infection Level, Nutritional and Productive Variables in a Tropical Farm Context: The Median Isn't the Message. Animals (Basel) 2024; 14:603. [PMID: 38396571 PMCID: PMC10886404 DOI: 10.3390/ani14040603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/13/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
We evaluated the relationship between individual and herd GIN infection level, nutrition, production performance and anemia parameters in a tropical farm context. Fifty-four female goats were monitored to assess their body condition score (BCS, nutritional status indicator), live weight (LW) and LW gain (LWG, both used as production level indicators), FAMACHA© and hematocrit (HT, both used as anemia indicators). Goats browsed for 4 h in a tropical forest and received balanced feed and chopped grass. The eggs per gram of feces (EPG) indicated the GIN burden, with fecal samples obtained at 7:00 (AM) and 15:00 h (PM.) from each goat at six sampling points during the study. The variables and their relationship with GIN burdens were analyzed using Kruskall-Wallis, ANOVA and Friedman tests and Spearman correlations. The fecal samples obtained in the AM and PM can be equally representative of parasitic burdens (similar and highly correlated). However, the EPG of individual goats from periods of 30 days apart can be considered independent. The BCS and LWG varied between sampling times (p < 0.05), whereas EPG, LW and HT did not (p > 0.05). The GIN burden was negatively correlated with HT and BCS (-0.21, p = 0.01 for each one). The individual pattern of infection demonstrates the true impact of GINs on their hosts. Additionally, feeding and nutritional status may present important variations influencing the performance of the goats more than the impact of GINs under the farm conditions of the present study. However, GIN infection contributed to the variation in goat health and productivity in this tropical farm.
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Affiliation(s)
- Gabriel Andrés Ortíz-Domínguez
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, Mérida C.P. 97315, Yucatán, Mexico; (G.A.O.-D.); (P.G.G.-P.); (J.F.d.J.T.-A.)
| | - Pedro Geraldo González-Pech
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, Mérida C.P. 97315, Yucatán, Mexico; (G.A.O.-D.); (P.G.G.-P.); (J.F.d.J.T.-A.)
| | - Juan Felipe de Jesús Torres-Acosta
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, Mérida C.P. 97315, Yucatán, Mexico; (G.A.O.-D.); (P.G.G.-P.); (J.F.d.J.T.-A.)
| | - Javier Ventura-Cordero
- Facultad de Ciencias Agropecuarias, Universidad Autónoma de Campeche, Calle 53 S/N, Col. Unidad, Esfuerzo y Trabajo #2, Escárcega C.P. 24350, Campeche, Mexico;
| | - Juan Villalba
- Department of Wildland Resources, Utah State University, Logan, UT 84322, USA;
| | - Carlos Alfredo Sandoval-Castro
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, Mérida C.P. 97315, Yucatán, Mexico; (G.A.O.-D.); (P.G.G.-P.); (J.F.d.J.T.-A.)
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Zaragoza-Vera CV, Gonzalez-Garduño R, Arjona-Jimenez G, Zaragoza-Vera M, Aguilar-Caballero AJ, Torres-Chable OM. Optimum timing for assessing phenotypic resistance against gastrointestinal nematodes in Pelibuey ewes. Helminthologia 2023; 60:348-356. [PMID: 38222487 PMCID: PMC10787634 DOI: 10.2478/helm-2023-0038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 10/27/2023] [Indexed: 01/16/2024] Open
Abstract
The objective was to identify the optimal stage of production to evaluate the resistance of Pelibuey ewes against gastrointestinal nematodes (GIN). Faecal egg count (FEC) was used to classify the ewes as resistant, sensible or intermediate against GIN. Forty-seven ewes were mating during 30 d. The gestation was verified by ultrasonography, and the breeding date was used to calculate the productive stages. Faeces were taken weekly to determine the FEC. Blood samples were taken to determine the packed cell volume (PCV), the peripheral eosinophils count (PEC), plasma protein concentration (PP), and Immunoglobulin A (IgA) against Haemonchus contortus. The body condition score (BCS) was recorded at each visit. Six moments during the study (early, mid and late gestation; early, mid and late lactation) were considered. The ewes were classified according to FEC (mean FEC ± three standard errors). The higher FEC occurred during all lactation stages than during early and mid-gestation stages (P<0.05). PCV, PP, and BCS during early gestation stage were higher than shown during the lactation stages (P<0.01). The PEC and IgA were higher during all lactation stages than early and mid-gestation stages (P<0.05). Concerning the type of birth, double births showed higher FEC than single birth (P<0.01). The highest values of accuracy (100 %) and concordance (Youden's J = 1.0) were found during early lactation. Therefore, it is concluded that the optimal stage of production to evaluate phenotypic resistance against GIN infections in Pelibuey ewes was during the early lactation.
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Affiliation(s)
- C. V. Zaragoza-Vera
- Laboratorio de Enfermedades Tropicales y Transmitidas por Vectores, Division Academica de Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Km. 25, Carretera Villahermosa-Teapa, R/a La Huasteca 2. Seccion, C.P.86298Villahermosa, Tabasco, Mexico
| | - R. Gonzalez-Garduño
- Unidad Regional Universitaria Sursureste, Universidad Autónoma Chapingo, km 7.5 Carretera Teapa-Vicente Guerrero, Teapa, Tabasco, Mexico
| | - G. Arjona-Jimenez
- Laboratorio de Enfermedades Tropicales y Transmitidas por Vectores, Division Academica de Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Km. 25, Carretera Villahermosa-Teapa, R/a La Huasteca 2. Seccion, C.P.86298Villahermosa, Tabasco, Mexico
| | - M. Zaragoza-Vera
- Laboratorio de Enfermedades Tropicales y Transmitidas por Vectores, Division Academica de Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Km. 25, Carretera Villahermosa-Teapa, R/a La Huasteca 2. Seccion, C.P.86298Villahermosa, Tabasco, Mexico
| | - A. J. Aguilar-Caballero
- Facultad de Medicina Veterinaria y Zootecnia, Campus de Ciencias Biologicas y Agropecuarias, Universidad Autonoma de Yucatan, Km. 15.5, Carretera Merida-Xmatkuil, Apdo. postal 4-116, 97100Merida, Yucatan, Mexico
| | - O. M. Torres-Chable
- Laboratorio de Enfermedades Tropicales y Transmitidas por Vectores, Division Academica de Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Km. 25, Carretera Villahermosa-Teapa, R/a La Huasteca 2. Seccion, C.P.86298Villahermosa, Tabasco, Mexico
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Effect of three feeding levels on the pathogenesis and establishment of Haemonchus contortus in parasite-naïve Pelibuey hair sheep lambs during their first infection. Vet Parasitol 2022; 311:109811. [DOI: 10.1016/j.vetpar.2022.109811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 09/26/2022] [Accepted: 10/05/2022] [Indexed: 11/21/2022]
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Méndez-Ortiz FA, Sandoval-Castro CA, Sarmiento-Franco LA, Ventura-Cordero J, González-Pech PG, Vargas-Magaña JJ, Torres-Acosta JFJ. Impact of Dietary Condensed Tannins and Haemonchus contortus Infection in Growing Sheep: Effects on Nutrient Intake, Digestibility, and the Retention of Energy and Nitrogen. Acta Parasitol 2022; 67:196-206. [PMID: 34264442 DOI: 10.1007/s11686-021-00441-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/11/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE A controlled study evaluated the effect of condensed tannins (CT) from Gymnopodium floribundum leaf meal (GF), infection with Haemonchus contortus (I) and their interaction, on feed intake, diet digestibility and retention of N (NR) and energy (ER) in hair sheep lambs. METHODS Thirty-six, worm-free hair sheep lambs (14.9 ± 1.56 kg body weight) were housed in metabolic cages. Eighteen animals were infected with 6000 H. contortus L3, while other 18 lambs were kept non-infected. On day 28th post-infection (PI), infected lambs were assigned to three diet groups: a diet without GF (I-NONGF), a diet with GF (I + GF) and a diet with GF + polyethylene glycol (PEG) (I + GF + PEG). Non-infected (NI) lambs were assigned to similar diet groups: NI-NONGF, NI + GF and NI + GF + PEG. The packed cell volume (% PCV), ante-mortem faecal egg counts and post-mortem worm burdens were also evaluated. RESULTS Infection did not affect digestibility, NR and ER. Meanwhile, CT intake from the GF diet reduced the digestibility of dry matter, organic matter and crude protein, as well as NR, compared to lambs consuming the NONGF and GF + PEG diets (P < 0.05). Although, the digestible energy was similar between lambs consuming NONGF and GF + PEG diets, the ER was higher for lambs consuming the control NONGF diet. Diets did not affect the PCV, or the ante-mortem and post-mortem parasitological variables. CONCLUSION The costs on N and energy metabolism were mainly associated with the CT content of the GF diet, but other features of the diet such as the high lignin content, seemed to affect animals consuming GF meal. Meanwhile, the H. contortus infection had a non-significant impact.
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Affiliation(s)
- F A Méndez-Ortiz
- Escuela Superior de Ciencias Agropecuarias, Universidad Autónoma de Campeche, Calle 53 S/N, Col. Unidad, Esfuerzo y Trabajo #2, Escárcega, CP 24350, Campeche, Mexico
| | - C A Sandoval-Castro
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97315, Mérida, Yucatán, Mexico
| | - L A Sarmiento-Franco
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97315, Mérida, Yucatán, Mexico
| | - J Ventura-Cordero
- School of Biological Sciences, Queen's University Belfast, Chlorine Gardens, Belfast, BT9 5BL, UK
| | - P G González-Pech
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97315, Mérida, Yucatán, Mexico
| | - J J Vargas-Magaña
- Escuela Superior de Ciencias Agropecuarias, Universidad Autónoma de Campeche, Calle 53 S/N, Col. Unidad, Esfuerzo y Trabajo #2, Escárcega, CP 24350, Campeche, Mexico
| | - J F J Torres-Acosta
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97315, Mérida, Yucatán, Mexico.
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Hoste H, Meza-OCampos G, Marchand S, Sotiraki S, Sarasti K, Blomstrand BM, Williams AR, Thamsborg SM, Athanasiadou S, Enemark HL, Torres Acosta JF, Mancilla-Montelongo G, Castro CS, Costa-Junior LM, Louvandini H, Sousa DM, Salminen JP, Karonen M, Engstrom M, Charlier J, Niderkorn V, Morgan ER. Use of agro-industrial by-products containing tannins for the integrated control of gastrointestinal nematodes in ruminants. Parasite 2022; 29:10. [PMID: 35225785 PMCID: PMC8884022 DOI: 10.1051/parasite/2022010] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/26/2021] [Indexed: 01/19/2023] Open
Abstract
Previous studies have illustrated that different bioactive legume fodders containing condensed tannins might represent one of the options for integrated sustainable control of gastrointestinal nematodes (GIN) in ruminants, which may help address the worldwide development of resistance to synthetic anthelmintics. More recently, impetus has been given to assess the potential antiparasitic activity of less conventional resources, represented by different agro-industrial by-products (AIBPs). This review presents in vitro and in vivo results obtained with a range of tannin-containing AIBPs of various geographical and botanical origins, namely AIBP of nuts, temperate and tropical barks, carob, coffee and cocoa. They tend to confirm the "proof of concept" for their antiparasitic effects and also for other aspects of ruminant production in an agro-ecological context. Socio-economic aspects of the exploitation of such non-conventional resources are also discussed as potential models of the circular economy, by using waste. The different modes of use of these resources are presented in this review, as well as strengths, weaknesses, opportunities, and threats (SWOT) analyses to illustrate the advantages and limitations of on-farm use.
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Affiliation(s)
- Hervé Hoste
- Université de Toulouse, UMR 1225 IHAP INRAE/ENVT 31076 Toulouse France
| | | | - Sarah Marchand
- Université de Toulouse, UMR 1225 IHAP INRAE/ENVT 31076 Toulouse France
| | | | | | | | | | | | | | | | - Juan Felipe Torres Acosta
- CONACYT-Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán Carretera Mérida-Xmatkuil km 15.5 Mérida Yucatán 97000 México
| | - Gabriella Mancilla-Montelongo
- CONACYT-Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán Carretera Mérida-Xmatkuil km 15.5 Mérida Yucatán 97000 México
| | - Carlos Sandoval Castro
- CONACYT-Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán Carretera Mérida-Xmatkuil km 15.5 Mérida Yucatán 97000 México
| | - Livio M. Costa-Junior
- Laboratório de Controle de Parasitos, Centro de Ciências Biológicas e da Saúde, Departamento de Patologia, Universidade Federal do Maranhão, São Luis Maranhão MA 65080-805 Brazil
| | - Helder Louvandini
- Laboratório de Nutrição Animal, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo 13400-970 Piracicaba São Paulo Brazil
| | - Dauana Mesquita Sousa
- Laboratório de Controle de Parasitos, Centro de Ciências Biológicas e da Saúde, Departamento de Patologia, Universidade Federal do Maranhão, São Luis Maranhão MA 65080-805 Brazil
| | | | - Maarit Karonen
- Natural Chemistry Research Group, University of Turku 20014 Turku Finland
| | - Marika Engstrom
- Natural Chemistry Research Group, University of Turku 20014 Turku Finland
| | | | - Vincent Niderkorn
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores 63122 Saint-Genes Champanelle France
| | - Eric R. Morgan
- School of Biological Sciences, Queens University, Belfast BT9 5DL Northern Ireland United Kingdom
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Comparing the browsing behavior of inexperienced kids versus adult goats on heterogeneous vegetation. Appl Anim Behav Sci 2021. [DOI: 10.1016/j.applanim.2021.105240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Can-Celis A, Mancilla-Montelongo G, Castañeda-Ramírez GS, Chan-Pérez JI, Torres-Acosta JFDJ. Isolation of pure Trichostrongylus colubriformis strains from naturally infected sheep using two methodologies. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2020; 22:100474. [PMID: 33308728 DOI: 10.1016/j.vprsr.2020.100474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/23/2020] [Accepted: 09/21/2020] [Indexed: 11/26/2022]
Abstract
Two methodologies were tested to isolate pure Trichostrongylus colubriformis strains from naturally infected sheep. Also, the in vitro susceptibility status to commercial anthelmintic (AH) drugs was determined in these strains. These methods were performed in a tropical region of Mexico where naturally infected sheep and goats host Haemonchus contortus, T. colubriformis and Oesophagostomum columbianum. For the first strain, a group of 6 naturally infected lambs from the "Paraiso" farm were treated with closantel (subcutaneous (SC), 10 mg/kg). On day 10 post-treatment, the eggs per gram (EPG) of faeces were determined with the McMaster technique. The faeces from the two lambs with the highest EPG were used for coprocultures (4 days, 28 °C). The L3 larvae were recovered and identified as T. colubriformis (69%) and O. columbianum (31%). The latter was removed by 10-day refrigeration (4-5 °C) followed by sieving (25 μm), resulting in 100% T. colubriformis (PARAISO strain). The second strain was isolated using repeated doses of levamisole (LEV, SC 7.5 mg/kg) in an 8-year-old sheep. The sheep had 1700 EPG before the LEV treatments and maintained 1300 EPG after both LEV treatments (day 10). The coproculture (4 days, 28 °C) after the second treatment contained 100% T. colubriformis (FMVZ-UADY strain). The in vitro AH susceptibility was determined using the egg hatch test for benzimidazole (BZ), and the larval migration inhibition test for ivermectin (IVM) and LEV. The PARAISO strain was BZ- and LEV-susceptible, and IVM-resistant. Meanwhile, the FMVZ-UADY strain was BZ- and IVM-susceptible, and LEV-resistant. The conditions where these two protocols could be used in other parts of the world were discussed.
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Affiliation(s)
- Alhely Can-Celis
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97100 Mérida, Yucatán, Mexico
| | - Gabriela Mancilla-Montelongo
- CONACYT - Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97100 Mérida, Yucatán, Mexico
| | - Gloria Sarahi Castañeda-Ramírez
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97100 Mérida, Yucatán, Mexico
| | - José Israel Chan-Pérez
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97100 Mérida, Yucatán, Mexico
| | - Juan Felipe de Jesús Torres-Acosta
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Km 15.5 Carretera Mérida-Xmatkuil, CP 97100 Mérida, Yucatán, Mexico.
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Torres-Fajardo RA, González-Pech PG, Sandoval-Castro CA, Torres-Acosta JFDJ. Small Ruminant Production Based on Rangelands to Optimize Animal Nutrition and Health: Building an Interdisciplinary Approach to Evaluate Nutraceutical Plants. Animals (Basel) 2020; 10:E1799. [PMID: 33023017 PMCID: PMC7601357 DOI: 10.3390/ani10101799] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/16/2020] [Accepted: 09/30/2020] [Indexed: 12/12/2022] Open
Abstract
The plant kingdom can influence the productivity and health of herbivores at different levels. However, demonstrating this process in a scientific manner entails substantial endeavors from different disciplines. In the present review, we will describe the features of a native vegetation system traditionally used by small ruminants and use its particularities to build an interdisciplinary approach to evaluate the nutraceutical properties of plants. Initially, we will establish the context of the low deciduous forest (LDF), considering some botanical and nutritional aspects, as well as the presence of plant secondary compounds (PSC) and gastrointestinal nematodes (GIN). Furthermore, we will focus on coevolutionary aspects that undoubtedly shaped the plants-nutrients-PSC-GIN-herbivore relationship. In addition, the concept of nutraceutical will be discussed to provide clarity and aspects to be considered for their evaluation. Then, ethological, agronomical, nutritional, PSC, parasitological and animal species issues are deepened placing emphasis on methodological approaches. Special focus is given to condensed tannins, as they are the fourth largest group of PSCs and the most studied in livestock sciences. Validation of the nutraceutical properties of plants from native vegetation systems should be seen as a process derived from many scientific disciplines that feed into each other in a cyclic manner.
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Affiliation(s)
| | | | - Carlos Alfredo Sandoval-Castro
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida 97000, Yucatán, Mexico; (R.A.T.-F.); (P.G.G.-P.); (J.F.d.J.T.-A.)
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Aguirre-Serrano A, Ojeda-Robertos N, González-Garduño R, Peralta-Torres J, Luna-Palomera C, Torres-Acosta J. Influence of litter size at birth and weaning on the proportion of Pelibuey ewes treated with an anthelmintic in a targeted selective scheme in the hot humid tropics. Small Rumin Res 2020. [DOI: 10.1016/j.smallrumres.2020.106049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Criollo goats limit their grass intake in the early morning suggesting a prophylactic self-medication behaviour in a heterogeneous vegetation. Trop Anim Health Prod 2019; 51:2473-2479. [PMID: 31197723 DOI: 10.1007/s11250-019-01966-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 06/04/2019] [Indexed: 10/26/2022]
Abstract
The present study compared the feeding behaviour of goats in the early morning (EM = 7:00-8:30 a.m.) and late morning (LM = 9:30-11:00 a.m.) in response to their natural gastrointestinal nematode (GIN) infection status. Twelve female adult goats (37 ± 7.7 kg live weight (LW); 5 ± 1 years) with browsing experience in the tropical deciduous forest were divided into two groups (n = 6): INF group, with natural GIN infection, and non-infected (NI) group, dewormed with moxidectin (0.4 mg/kg LW subcutaneous). Feeding behaviour (dry matter intake (DMI)) of two resource types (grasses vs. shrubs + herbs) was estimated by direct observation for 4 weeks on two grazing moments (EM vs. LM). Environmental temperature and relative humidity at pasture level were measured twice weekly. The GIN egg counts and goats' LW were measured on days 0, 14 and 28. Temperature (mean ± standard deviation) at EM (26.2 ± 1.5 °C) was lower than at LM (38.7 ± 1 °C; P < 0.01). Humidity was higher on the EM (85.1 ± 2.6%) compared to LM (60.4 ± 5.6%; P < 0.01). Irrespective of the infection status, goats consumed similar amounts of grass and shrubs + herbs during EM (P > 0.05). On the other hand, the experimental groups consumed more grass than shrubs + herbs during LM (P < 0.05). The latter suggested prophylactic behaviours strategies to (a) avoid GIN infective larvae, (b) balance the protein:energy ratio of the diet and (c) avoid saturation of detoxification pathways for the secondary compounds consumed from shrubs + herbs. The constant consumption of shrubs + herbs during the study may have reduced the GIN egg count of the INF group.
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