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

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 \u3c 0.05), whereas EPG, LW and HT did not (p \u3e 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

¿La suplementación energética de las ovejas puede influenciar el desempeño conductual de sus corderos neonatos?

The present work evaluated the effect of an energetic supplement (an extra 15% of the requirement) intake during the last month of gestation on the suckling behavior of neonatal lambs born from these ewes. The study was performed in a semi-intensive and commercial flock under hot sub humid tropical conditions. 12 Pelibuey ewes and their 20 newborn lambs were included. Five lamb behaviors were evaluated: number of vocalizations (NV), attempts to stand up (ASU), latency to keep stands (LKS), started looking for the udder (SLU) and achieved an effective suckling (AES). Twelve lambs conformed the control group [CG] and came from seven ewes which received an energetic supplementation of 7.37 megajoules of metabolizable energy per day (MJ EM/d). Likewise, eight lambs conformed the treatment group [TG] and came from five ewes which received a high energetic supplementation of 10.85 MJ EM/d. Both groups of ewes gave birth simultaneously. Response variables were initially categorized in low-or-high intensity using their quartile distribution and considering the median value as the reference point and analyzed post-hoc with the Fisher test. Behaviors of high and low intensity in lambs were similar in four of the five variables observed for both treatments. A significant difference was observed in the frequency of ASU, in lambs born from treated ewes when compared with lambs born from control ewes (P = 0.0281). The present results suggest that under semi-extensive breeding systems, the extra supplementation of ewes at 15 % of their energetic requirements during the last pregnancy month is reflected just in a slight improvement of the lamb’s behaviors.El presente trabajo evaluó el efecto del consumo de un suplemento energético (15 % extra del requerimiento) durante el último mes de gestación sobre la conducta de amamantamiento de los corderos neonatos nacidos de estas ovejas. El estudio se realizó en una granja comercial semi-intensiva bajo condiciones tropicales cálidas subhúmedas. Se incluyeron 12 ovejas Pelibuey y sus 20 corderos recién nacidos. Se evaluaron cinco conductas del neonato: número de vocalizaciones (NV), intentos para ponerse en pie (IQP), latencia para ponerse pie (LDP), comienzo de la búsqueda de la ubre (BU) y amamantamiento efectivo (AE). Doce corderos conformaron el grupo control [GC] y provenían de 7 ovejas que recibieron una suplementación energética de 7.37 mega julios de energía metabolizable por día (MJ EM/d). Por su parte, ocho corderos conformaron el grupo tratado [GT] y provenían de 5 ovejas que recibieron una suplementación energética alta (10.85 MJ EM/d). Ambos grupos parieron de manera simultánea. Las variables de respuesta fueron inicialmente categorizadas como de baja o alta intensidad utilizando la distribución de sus cuartiles y considerando el valor de la mediana como punto de corte y analizadas post-hoc a través de la prueba de Fisher. Las conductas de alta y baja intensidad de los neonatos fueron similares en cuatro de los cinco comportamientos observados en ambos tratamientos. Se observó una diferencia significativa en la frecuencia de intentos para ponerse de pie en los corderos de ovejas tratadas comparados a los corderos de ovejas control (P = 0.0281). Estos resultados sugieren que en sistemas de crianza semi-intensivos, la suplementación extra del 15 % de las madres durante el último mes de gestación solo se refleja en una ligera mejoría de las conductas de sus neonatos

Age of Haemonchus contortus third stage infective larvae is a factor influencing the in vitro assessment of anthelmintic properties of tannin containing plant extracts

The larval exsheathment inhibition assay (LEIA) of infective larvae (L3) is an in vitro method used to evaluate the anthelmintic (AH) activity of tannin-containing plant extracts against different species of gastrointestinal nematodes, including Haemonchus contortus. Some conditions remain to be defined in order to standardize the LEIA, i.e. the optimal age of larvae produced from donor animals to use in the assays. Therefore, this study aimed at identifying the effect of age and age-related vitality of H. contortus infective larvae produced under tropical conditions, on the in vitro AH activity measured with the LEIA. The same acetone:water (70:30) extract from Acacia pennatula leaves was used to perform respective LEIA tests with H. contortus L3 of different ages (1–7 weeks). Each week, the L3 were tested against different concentrations of extract (1200, 600, 400, 200, 100, 40μg/mL of extract) plus a PBS control. Bioassays were performed with a benzimidazole (Bz) resistant H. contortus (Paraíso) strain. In order to identify changes in L3 vitality on different weeks (1–7), two assays testing larval motility were included only with PBS: the larval migration assay (LMA) and the larval motility observation assay (LMOA). Mean effective concentrations causing 50% and 90% exsheathment inhibition (EC50, EC90) were obtained for every week using respective Probit analyses. On the first week, the larvae had lowest EC50 and EC90 (39.4 and 65.6μg/mL) compared to older larvae (P0.05), while older larvae tended to show higher EC50 and EC90 (P<0.05). Motility showed strong negative correlations with age of larvae (r≥−0.83; P <0.05) and EC50 (r≥−0.80; P<0.05), suggesting that the lower extract efficacy could be associated with decaying vitality of larvae associated with age. More stable efficacy results were found between two to five weeks of age

Is there a negative association between the content of condensed tannins, total phenols, and total tannins of tropical plant extracts and in vitro anthelmintic activity against Haemonchus contortus eggs?

In vitro studies using plant extracts suggest a relationship between their polyphenol contents and their anthelmintic (AH) activity against Haemonchus contortus. High polyphenol content appears to increase the efficacy of plant extracts against H. contortus as assessed by the larval exsheathment inhibition assay (LEIA) while appearing to reduce the AH efficacy measured using the egg hatch assay (EHA). In addition, some plants lack AH activity. Therefore, the present study investigated the relationship between the contents of condensed tannins (CT), total phenols (TP), and total tannins (TT) in methanol:water extracts (70:30) obtained from ten tropical plant species consumed by small ruminants as well as their AH activity against H. contortus evaluated by LEIA and EHA. Extracts of Acacia collinsii, Lysiloma latisiliquum, Havardia albicans, Senegalia gaumeri, Mimosa bahamensis, Piscidia piscipula, Acacia pennatula, Gymnopodium floribundum, Leucaena leucocephala, and Bunchosia swartziana were examined. Positive correlations were found between the effective concentration 50% (EC50) (EHA) of extracts and their CT (r = 0.6809, P < 0.05, n = 10) and TP (r = 0.9152, P < 0.05, n = 10) content, suggesting that their concentration negatively affected AH activity against eggs. Based on the LEIA, there was no significant association between the EC50 and the CT, TP, or TT of all extracts evaluated. Thus, if sheep and goats consume a complex feed mixture with high amounts of CT, TP, and TT, it might be difficult to observe an AH effect against H. contortus egg hatching. However, the AH effect upon L3 establishment might be feasible

An in vitro approach to evaluate the nutraceutical value of plant foliage against Haemonchus contortus

Nutraceutical plants provide nutrients for the animal as well as secondary compounds that can affect the biology and survival of gastrointestinal nematodes (GIN). Current screening of nutraceutical plants is based on in vitro evidence of anthelmintic (AH) activity against different life stages of GIN, but nutritional information is omitted or scarce. This study proposes an integral in vitro screening protocol to identify the nutraceutical value of the foliage from plant species consumed by small ruminants, using Haemonchus contortus as a biological model. The leaves from Acacia collinsii, A. pennatula, Bunchosia swartziana, Gymnopodium floribundum, Havardia albicans, Leucaena leucocephala, Lysiloma latisiliquum, Mimosa bahamensis, Piscidia piscipula, and Senegalia gaumeri were evaluated for their chemical composition and in vitro digestibility. Acetone:water extracts (70:30) from leaves of each plant were evaluated using the egg hatch assay and larval exsheathment inhibition assay. Respective effective concentrations 50% (EC50) were determined for each assay. The ten plant species showed good nutritional value for ruminants, including crude protein (> 10%), metabolizable energy (> 2.9 MJ/kg DM), and varied CT content (from 1.0 to 37.6%). The best AH activity against H. contortus eggs (EC50 = 401.8 μg/mL) and L3 (EC50 = 83.1 μg/mL) was observed for S. gaumeri extract. Although all the plant species showed in vitro nutraceutical potential, the leaves of S. gaumeri had the best values. The proposed in vitro protocol showed to be useful for the integral assessment of the nutraceutical potential of different plant species as it included the nutritional value and the AH activity against eggs and L3 in the selected plant species

Nutraceutical Potential of the Low Deciduous Forest to Improve Small Ruminant Nutrition and Health: A Systematic Review

Nutraceuticals are defined as livestock feeds that combine their nutritional value with their beneficial effects on animal health. We analyzed the outcomes from nearly 20 years of research assessing the nutraceutical properties of plants consumed by sheep and goats in low deciduous forests. A systematic review of different databases suggested 31 peer-reviewed manuscripts according to pre-established criteria. Amongst these, 16 manuscripts described in vitro evaluations investigating the bioactivity of plant secondary compounds in the extracts of 12 plant species. Most of these studies used the abomasal nematode Haemonchus contortus as the parasite model. Meanwhile, 11 manuscripts reported in vivo trials under controlled pen conditions, evaluating the relationships between the intake of leaves from different plant species and their secondary compounds and animal nutrition, performance, and gastrointestinal nematode infections. Additionally, four manuscripts described studies under natural feeding conditions. Altogether, the studies showed the inherent complexity of the relationship between small ruminants, plants, nutrients, secondary compounds, and gastrointestinal nematodes in natural feeding systems. Several plant species can be considered good candidates for nutraceutical use. Our findings warrant future work to understand the relationship between plants, ruminants, and their parasites, with the aim to improve the sustainability of production systems based on the native vegetation of tropical forests

¿La suplementación energética de las ovejas puede influenciar el desempeño conductual de sus corderos neonatos?

The present work evaluated the effect of an energetic supplement (an extra 15% of the requirement) intake during the last month of gestation on the suckling behavior of neonatal lambs born from these ewes. The study was performed in a semi-intensive and commercial flock under hot sub humid tropical conditions. 12 Pelibuey ewes and their 20 newborn lambs were included. Five lamb behaviors were evaluated: number of vocalizations (NV), attempts to stand up (ASU), latency to keep stands (LKS), started looking for the udder (SLU) and achieved an effective suckling (AES). Twelve lambs conformed the control group [CG] and came from seven ewes which received an energetic supplementation of 7.37 megajoules of metabolizable energy per day (MJ EM/d). Likewise, eight lambs conformed the treatment group [TG] and came from five ewes which received a high energetic supplementation of 10.85 MJ EM/d. Both groups of ewes gave birth simultaneously. Response variables were initially categorized in low-or-high intensity using their quartile distribution and considering the median value as the reference point and analyzed post-hoc with the Fisher test. Behaviors of high and low intensity in lambs were similar in four of the five variables observed for both treatments. A significant difference was observed in the frequency of ASU, in lambs born from treated ewes when compared with lambs born from control ewes (P = 0.0281). The present results suggest that under semi-extensive breeding systems, the extra supplementation of ewes at 15 % of their energetic requirements during the last pregnancy month is reflected just in a slight improvement of the lamb’s behaviors.El presente trabajo evaluó el efecto del consumo de un suplemento energético (15 % extra del requerimiento) durante el último mes de gestación sobre la conducta de amamantamiento de los corderos neonatos nacidos de estas ovejas. El estudio se realizó en una granja comercial semi-intensiva bajo condiciones tropicales cálidas subhúmedas. Se incluyeron 12 ovejas Pelibuey y sus 20 corderos recién nacidos. Se evaluaron cinco conductas del neonato: número de vocalizaciones (NV), intentos para ponerse en pie (IQP), latencia para ponerse pie (LDP), comienzo de la búsqueda de la ubre (BU) y amamantamiento efectivo (AE). Doce corderos conformaron el grupo control [GC] y provenían de 7 ovejas que recibieron una suplementación energética de 7.37 mega julios de energía metabolizable por día (MJ EM/d). Por su parte, ocho corderos conformaron el grupo tratado [GT] y provenían de 5 ovejas que recibieron una suplementación energética alta (10.85 MJ EM/d). Ambos grupos parieron de manera simultánea. Las variables de respuesta fueron inicialmente categorizadas como de baja o alta intensidad utilizando la distribución de sus cuartiles y considerando el valor de la mediana como punto de corte y analizadas post-hoc a través de la prueba de Fisher. Las conductas de alta y baja intensidad de los neonatos fueron similares en cuatro de los cinco comportamientos observados en ambos tratamientos. Se observó una diferencia significativa en la frecuencia de intentos para ponerse de pie en los corderos de ovejas tratadas comparados a los corderos de ovejas control (P = 0.0281). Estos resultados sugieren que en sistemas de crianza semi-intensivos, la suplementación extra del 15 % de las madres durante el último mes de gestación solo se refleja en una ligera mejoría de las conductas de sus neonatos

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

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 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

Selection of Forage Resources by Juvenile Goats in a Cafeteria Trial: Effect of Browsing Experience, Nutrient and Secondary Compound Content

SIMPLE SUMMARY: Grazing/browsing goats ingest a diverse diet selected from the forage resources available in the range/paddock intending to meet their nutritional requirements. Intake and selection of any given forage can be modified by several factors, such as its nutrient content, including secondary compounds, as well as its biomass availability in the environment. The animal’s previous browsing experience can also be an important factor driving intake and selection. Therefore, the present study evaluated all these factors as well as their interaction. The results showed that the goats’ browsing experience guided the selection and intake towards those forage resources of better nutritional quality when there was no restriction in forage supply, as is the case for cafeteria trials. Goats with browsing experience showed their ability to limit secondary compounds and optimize their selection and intake for plants with better digestibility. This cafeteria protocol made it possible to identify the selection and consumption pattern of plant species with limited availability in the natural vegetation. This methodology could help identifying the forage resources that may be useful for small ruminant feeding, versus those resources that are not consumed by goats despite having a suitable chemical composition and in vitro digestibility or a high abundance. ABSTRACT: We evaluated the effect of browsing experience, nutritional quality and secondary compounds of forage resources, and the interaction between these factors on the selection and intake of goats in a cafeteria trial. Twelve juvenile Criollo goats from 7 to 9 months of age, weighing 22 ± 3 kg, were divided into two groups: (a) browser goats group (n = 6, BG), and (b) naïve goats group (n = 6, NG), formed according to their previous browsing experience (with and without, respectively). Animals were housed in individual pens. The cafeteria experiment lasted 21 days considering pen adaptation, foliage adaptation, and measurements, which included the selection index (SI) of experimental forage resources (Chesson’s alpha) and their dry matter intake (DMI/Kg(0.75)), using a multiple Latin square design. Furthermore, correlation and regression analyses were used to assess the relationship between the aforementioned factors. The NG did not show any selection pattern, while the BG selected Piscidia piscipula and Senegalia gaumeri (p = 0.0002). The BG consumed smaller amounts of secondary compounds compared to NG (p = 0.0001). In the BG, the flavonoids affected negatively their selection (R(2) = 97.51, p = 0.0001), while the DMI was affected by in vitro DM digestibility and flavonoids (R(2) = 99.85; p = 0.0001). For the NG, the crude protein and organic matter contents were associated with DMI, but none had a significant relationship with SI. The BG selected and consumed forages with suitable nutritional quality avoiding those with high content of secondary compounds such as flavonoids. Conversely, NG did not show a clear pattern for their selection or intake

A Review of the Impact of Climate Change on the Epidemiology of Gastrointestinal Nematode Infections in Small Ruminants and Wildlife in Tropical Conditions

Climate change is causing detrimental changes in living organisms, including pathogens. This review aimed to determine how climate change has impacted livestock system management, and consequently, what factors influenced the gastrointestinal nematodes epidemiology in small ruminants under tropical conditions. The latter is orientated to find out the possible solutions responding to climate change adverse effects. Climate factors that affect the patterns of transmission of gastrointestinal parasites of domesticated ruminants are reviewed. Climate change has modified the behavior of several animal species, including parasites. For this reason, new control methods are required for controlling parasitic infections in livestock animals. After a pertinent literature analysis, conclusions and perspectives of control are given