Response Of Goats Research Articles

Drinking water intake, milk production, and grazing behaviour of alpine dairy goats in response to daytime water restriction on temperate pastures

Certain local breeds of goats have adapted to severe water restriction in arid and semi-arid regions, but little is known about the adaptability of high-producing dairy goats to water restriction while grazing under temperate conditions. The aim of this study was to assess effects of water restriction of lactating Alpine goats during the daytime at pasture (8 h/d) on herd-level drinking water intake and individual milk production and grazing time. Goats remained in the barn between evening and morning milkings, where each animal was offered 600 g of concentrate and 400 g of hay each day, with free access to water. Twenty four goats were used in a crossover design, for two consecutive 14-d periods. The study was conducted in early summer, with a daily mean ambient temperature of 18.2 ± 3.5 °C (range of 13–27 °C over all the study days), a mean temperature-humidity index of 64 ± 4.9 (range of 56–76). Goats had access to a high-quality multispecies pasture with a mean of 216 ± 44 g DM/kg fresh matter. Total drinking water intake averaged 5.57 L/d and did not differ significantly between treatments. Goats with water access at pasture drank a mean of 1.88 L of water per day during the grazing period, but drank 2.24 L less per day in the barn than goats without water access at pasture. Drinking water intake increased by 0.57 L per day for each °C increase in daily mean ambient temperature. Daily milk production, milk composition, body weight, and daily grazing time did not differ between treatments. Only the duration of the first morning meal at pasture differed significantly between treatments. Thus, water restriction for 8 h per day during grazing periods does not seem to influence the variables measured for Alpine dairy goats under temperate conditions.

Effect of glucose infusion on glucose and insulin metabolism in early- and mid-lactation ewes and goats fed diets differing in starch and highly digestible fiber concentration

This study aimed to test possible metabolic differences between ewes and goats in response to an intravenous glucose infusion. Thirty-six animals, 18 mature Sarda dairy ewes and 18 mature Saanen goats (from 15 to 150 ± 11 d in milk [DIM], mean ± SD; body weight: 49.8 ± 6.8 kg for ewes, 60.6 ± 7.3 kg for goats) were compared simultaneously. In early lactation, both species received the same high-starch diet (HS: 20.4% starch, 35.4% neutral detergent fiber [NDF], on dry matter [DM] basis), whereas from 92 ± 11 DIM both species were randomly allocated to 2 dietary treatments: HS (20.0% starch, 36.7% NDF, on DM basis) and low-starch (LS: 7.8% starch, 48.8% NDF, on DM basis) diets. At 50 and 150 ± 11 DIM, ewes and goats were challenged with an intravenous glucose tolerance test and peripheral concentrations of glucose and insulin were determined 15 min before and 5, 10, 15, 30, 45, 90, and 180 min after glucose infusion. In early lactation, baseline plasma glucose and insulin concentrations tended to be higher in ewes than in goats (glucose: 55.8 vs. 42.9 ± 7.3 mg/dL; insulin: 0.13 vs. 0.05 ± 0.04 µg/L). After glucose infusion, glucose and insulin concentrations were higher in ewes than in goats (278.6 vs. 247.6 ± 13.1 mg/dL; 0.82 vs. 0.46 ± 0.12 µg/L). In mid-lactation, the dietary treatment (HS vs. LS) did not affect glucose and insulin metabolism. Baseline plasma glucose was numerically highest in ewes, while baseline insulin was higher in ewes than in goats (0.39 vs. 0.12 ± 0.099 µg/L). After glucose infusion, glucose concentration did not differ between ewes and goats, while insulin concentration was highest in ewes. Compared with goats, ewes showed in both periods a higher peak insulin, insulin increment, linear insulin area under the curve, insulin resistance index, and lower insulin sensitivity indices. In conclusion, despite the limitations associated with the use of intravenous glucose tolerance test to assess glucose regulation mechanisms, this study indicated large species differences in both early and mid-lactation and a more evident anabolic status in the ewes compared with the goats.

Feed intake and milk yield and composition of lactating dairy goats in response to partial substitution of soybean meal for formaldehyde-treated sesame meal in the diet

ABSTRACT This study was conducted to evaluate the effect of substitution of soybean meal (SBM) for formaldehyde-treated sesame meal (FTSM) on nutrient intake and digestibility, ruminal and blood parameters and milk production and composition in lactating Murciano-Granadina goats. Forty lactating goats were randomly assigned to one of the following four treatments: (1) diet with 16.5% CP, containing SBM (CON); (2) diet with 16.5% CP, containing untreated SM (USM); (3) diet with 16.5% CP, containing FTSM (FT); and (4) diet with 14.5% CP containing FTSM (LPFT). The results showed that nutrient intake was highest in the FT group (p < 0.001), while it was similar between the CON and LPFT groups, except for the intake of CP, which was higher in the CON group. The FT and LPFT had lower ruminal pH compared to CON and USM groups (p < 0.001), with goats in group FT having the highest volatile fatty acids (VFA) production (p < 0.001). The highest propionate concentration was observed in the LPFT treatment (p < 0.001), followed by the FT, CON, and USM treatments. Goats offered USM and LPFT treatments presented the highest and lowest acetate: propionate values, respectively, among the experimental groups (p < 0.001). The results also showed that LPFT goats had the lowest blood urea nitrogen (BUN) level (p = 0.004), while FT goats presented a lower non-esterified FA (NEFA) level compared with CON and LPFT goats (p = 0.01). Goats offered the FT diet had the highest milk yield (p = 0.002) and energy-corrected milk yield (p < 0.001) among all dietary groups. The highest milk fat (p < 0.001), protein (p = 0.001), lactose (p = 0.007), total solids (p = 0.003), and solids-not-fat (SNF) (p = 0.003) contents were observed in FT goats, which didn’t differ from USM goats. The inclusion of formaldehyde-treated SM increased the percentage of C18:3 (p < 0.001) and C20:1 (p = 0.04) FAs compared with USM and CON treatments. Milk from USM, FT, and LPFT goats had lower levels of saturated (p < 0.001) and medium-chain FAs (p = 0.014) compared with CON goats, whereas milk from CON goats had lower levels of unsaturated, monounsaturated, and long-chain FAs compared to other groups (p < 0.001). The lowest and the highest concentrations of polyunsaturated FAs were observed in CON and LPFT goats, respectively (p = 0.001). It can be concluded that SBM can be advantageously replaced by formaldehyde-treated SM in the diet as a feasible alternative to improve feed intake and production performance of dairy goats.

Changes in the gene expression profile of the mammary gland lipogenic enzymes in Saanen goats in response to dietary fats.

The second half of the first pregnancy is a critical period in the growth and development of the mammary gland. The use of functional compounds during this period may positively impact livestock performance. In this study, changes in lipogenic enzyme gene expression in the mammary gland of Saanen goats in response to different dietary fat sources were analysed. Goats from four groups (10 each) received these diets from the last two months of pregnancy through four months of lactation: C-, no added fat (negative control group), C+, with saturated palm oil (positive control group), SB, with roasted soybeans (omega-6 group) and FS, with extruded flaxseed (omega-3 group). The fat content was about 4% of dry matter. Milk yield, milk fatty acid profile, milk health index (HI) and gene expression of four lipogenic enzymes in mammary tissue were measured. The FS group had significantly higher milk production with lower omega-6 to omega-3, monounsaturated to polyunsaturated, and total saturated fatty acids compared to other groups. The shorter and longer than16-carbon chain of total milk fatty acid indicates significantly higher values for the C- and C+ groups, respectively. The milk HI for the SB group was significantly higher. The gene expression profile for acetyl-coenzyme A carboxylase was higher in the C- group than other experimental groups. The results show that manipulation of the diet with unsaturated fat supplements improved milk production, synthesis of milk fat and molecular expression of lipogenic enzymes in mammary tissue in primiparous Saanen goats.

The expression of nutrient chemosensing gate molecules in the ileum and colon is altered for goats fed on a high-grain diet.

Limited knowledge is clarified about alterations in the related expression of nutrient chemosensors in the distal small intestine and hindgut under a high-grain (HG) diet in small ruminants. Herein, this study was performed to investigate the expression changes related to nutrient sensing and transport in the ileal and colonic epithelium of goats in response to feeding an HG diet. Twelve Liuyang black goats (similar age and weight) were randomly assigned into two groups: an HG diet (concentrate: hay = 90:10) and a CON diet (concentrate: hay = 55:45). Immunohistochemistry was applied to detect morphological changes in the gut epithelium together with altered expression of chemosensors in the ileum and colon. The results showed that feeding an HG diet increased ileal villus height and depth and induced mucosal sloughing in the colon. The expressions of the nutrient transporters GLUT2, GLUT5, SGLT2, CD36, rBAT, EAAT3, and LAT2 and sensing receptors GPR43 and T1R1 were promoted in the ileum under HG conditions. Moreover, feeding an HG diet also enhanced the expression of GLUT2, SGLT2, CD36, and GPR43 in the colon. These findings indicate that adaptation of the gastrointestinal tract to the HG diet promoted the absorption of glucose, fatty acids, and amino acids in goats.

Liveweight gain and metabolisable energy requirements of young entire male Australian Rangeland goats in response to supplementation

Context High international demand for goat meat and high prices for goat in Australia have resulted in a transition from opportunistic harvesting to more managed production systems for Rangeland goats. There is limited information available to establish feeding strategies to maximise growth rates of Rangeland goats within these developing managed production systems. Aims The aim of these experiments was to determine the response to supplements and the metabolisable energy requirements for maintenance and liveweight gain of young entire male Rangeland goats. Methods Dose–response relationships to various supplements were established in two experiments with young entire male Rangeland goats. In Experiment 1, 54 goats were allocated to rolled-wheat grain, rolled-sorghum grain, or lucerne pellet supplements offered from 0 (control) to 24 g dry matter/kg liveweight.day. In Experiment 2, 24 goats were allocated to a commercial starch-based pellet offered from 0 (control) to ad libitum. In both experiments, goats were held in individual pens and offered their daily supplement allowances with ad libitum access to Mitchell grass hay and drinking water for 70 days. Key results Total intake (30 to 32 g dry matter/kg liveweight.day) increased in a linear fashion with an increasing intake of all supplements. Maximum intake of rolled-wheat, rolled-sorghum, lucerne pellets and the commercial starch-based pellet supplements ranged from 18 to 22 g dry matter/kg liveweight.day. Unsupplemented goats lost liveweight (−20 to −32 g/day), while supplemented goats gained liveweight (0 to 126 g/day) in a linear fashion with an increasing supplement and metabolisable energy intake for all supplements, with the highest response in goats supplemented with the commercial starch-based pellets. Estimated metabolisable energy requirements to maintain liveweight (372 kJ/kg liveweight0.75.day) and for liveweight gain (35 kJ/g) of the goats were the same in both experiments. Conclusion Liveweight gain increased in a linear fashion with metabolisable energy intake, with the maximum rates of liveweight gain occurring when starch-based supplement intake was approximately 20 g dry matter/kg liveweight.day. Implications Supplementation with starch-based rations will increase liveweight gain and decrease age at turn-off of young entire male Rangeland goats; however, the local availability and cost of these supplements need to be considered.

Metabolic and behavior responses of lactating goats under heat stress

Heat stress (HS) negatively affects animal performance, but little is known about energetic metabolism and behavior changes in dairy goats under HS conditions. Eight multiparous Murciano-Granadina dairy goats (43.3 ± 1.6 kg BW; 2 ± 0.04 L milk/d; 81 ± 3 days of lactation) were kept in metabolism cages and randomly assigned to two treatments varying in the temperature humidity index (THI). The design was crossover (two 28-d periods), and treatments were: 1) thermal neutral (TN; 15–20C, 40–45% humidity, THI = 59–65), and 2) heat stress (HS, 12 h/d at 37°C and 40%, and 12 h/d at 30°C and 40%, THI = 86 and 77, respectively). Jugular silicon catheters were fitted, and glucose tolerance test (0.25 g/kg BW), insulin tolerance test (4.6 μg/kg BW) and epinephrine challenge (2 μg/kg BW) were conducted. Before and after each metabolite administration, blood samples were collected for the analysis of insulin, glucose, and nonesterified fatty acids (NEFA). Also, behavior variables (position changes, duration of remaining standing, as well as eating and drinking bouts and duration) were observed at day 3 of each period by video cameras. Heat stress reduced (P < 0.01) feed intake (−29%), milk yield (−10%), milk fat (–12%), milk protein (–14%), and milk casein (–13%). Goats in both groups had similar blood NEFA after insulin administration, but NEFA values were greater (P < 0.05) in TN than HS goats after epinephrine infusion. The HS goats secreted lower (P < 0.05) amounts of insulin than TN goats in response to the glucose tolerance test. Additionally, TN and HS goats had similar number of eating bouts, but the duration of each bout was shorter in HS than in TN. Also, HS had greater number of drinking bouts with no differences in drinking bout durations between groups. In conclusion, body lipid tissue of HS goats became more resistant to lipolysis, making them unable to mobilize body fat reserves despite the negative energy balance. In addition, the reduction in feed intake by HS was because of the shorter time of eating bouts, whereas the greater water consumption was related to the increase in drinking bouts.

Changes in the Rumen Bacteriome Structure and Enzymatic Activities of Goats in Response to Dietary Supplementation with Schizochytrium spp.

With the aim to produce functional dairy products enriched with polyunsaturated fatty acids (PUFA) by using feed supplements, radical changes could occur in the rumen microbiome. This work investigated the alterations of the rumen bacteriome of goats fed with PUFA-rich marine microalgae Schizochytrium spp. For the trial, twenty-four goats were divided into four homogenous clusters (six goats/treatment) according to their fat-corrected (4%) milk yield, body weight, and age; they were individually fed with alfalfa hay and a concentrate (F/C = 50/50). The concentrate of the control group (CON) contained no microalgae, while those of the treated groups were supplemented daily with 20 (ALG20), 40 (ALG40), and 60 g (ALG60) of Schizochytrium spp./goat. Rumen fluid samples were collected using a stomach tube during the 20th and 40th days of the experiment. The microbiome analysis using a 16S rRNA sequencing platform revealed that Firmicutes were decreased in microalgae-fed goats, while Bacteroidetes showed a tendency to increase in the ALG40 group due to the enhancement of Prevotellaceae. Cellulolytic bacteria, namely Treponema bryantii, Ruminococcus gauvreauii, R. albus, and R. flavefaciens, were decreased in the ALG40 group, resulting in an overall decrease of cellulase activity. In contrast, the amylolytic potential was significantly enhanced due to an upsurge in Ruminobacter amylophilus, Succinivibrio dextrinosolvens, and Fretibacterium fastidiosum populations. In conclusion, supplementing goats’ diets with 20 g Schizochytrium spp. could be considered a sustainable and efficient nutritional strategy to modulate rumen microbiome towards the development of dairy products enriched with bioactive compounds, while higher levels induced substantial shifts in determinant microbes’ populations.

Unpalatable plants induce a species-specific associational effect on neighboring communities

In grazing conditions, unpalatable species may induce either associational defense or neighbor contrast susceptibility in neighboring communities. Using surveys from eight grasslands, we tested whether various unpalatable species have the same impacts on neighboring communities in response to grazing. The studied unpalatable species were: Phlomis cancellata (an unpalatable nonpoisonous plant), Euphorbia boissieriana, E.microsciadia (poisonous plants), and Seseli transcaucasicum (a highly poisonous plant). Our results showed that, in the ungrazed grasslands, communities containing P. cancellata had lower biodiversity than communities without it. In the moderately- and heavily grazed grasslands, P. cancellata induced associational defense in the neighboring communities. In heavily grazed grasslands, both Euphorbia species promoted neighbor contrast susceptibility in the neighboring communities. Similarly, S. transcaucasicum in a heavily grazed grassland, induced neighbor contrast susceptibility. Different responses of plant community vulnerability among the studied unpalatable plants might be due to herbivore different foraging decisions. Accordingly, grazers selectively choose from other patches when facing P. cancellata and other plant individuals when there is a poisonous plant in a patch. Our results suggested that grazing intensity may not substantially affect the foraging decisions of sheep and goats in response to unpalatable species. We recommend monitoring the abundance of poisonous species to maintain the sustainable use of grasslands.

Physiological status naturally infected gastrointestinal goats in response to polyherbal supplementation and Melastoma malabathricum extract

This study aimed to determine the effect of polyherbal supplementation and Melastoma malabathricum extract on the physiological status of naturally infected gastrointestinal parasite on Peranakan Etawa goats. Twenty goats were divided into five treatments, in which four treatments were infected animals and one treatment was used as an uninfected control animal. The five treatments were: T1= Non-polyherbal pellets + Ivermectin, T2= Andrographis paniculata + Curcuma mangga + Nigella sativa, T3= Andrographis paniculata + Curcuma domestica + Nigella sativa, T4= Curcuma mangga + Curcuma domestica + Nigella sativa, and T5= Uninfected control + Non-polyherbal pellets. Melastoma malabathricum extract was also given to T2, T3, and T4 to substitute Ivermectin. Parameters measured were rectal temperature, respiration rate, pulse rate, HTC, and THI. Results showed that there was no significant difference among the treatments on respiration rate, but highly significant (p<0.01) on rectal temperature and pulse rate. The pulse rate was significantly higher (p<0.05) in uninfected animals having THI value of 77-86 representing the hot condition for goats. Those goats could adopt its environment during the study as indicated by the HTC value of 2.15-2.28. Results also showed that HTC value was strongly correlated with the respiration rate (coefficient correlation 0.9987).

Alterations in the Rumen Particle-Associated Microbiota of Goats in Response to Dietary Supplementation Levels of Schizochytrium spp.

Fat rich microorganisms, such as microalgae Schizochytrium spp., are potential biotechnological tools in the modulation of rumen microbiome towards ecofriendly and high nutritional value end-products. However, limited in vivo trials have been reported on the topic. The aim of this study was to contribute to the knowledge on the effect of fat rich microalgae on the methanogenic and feed degrading particle-associated microbes in goats’ rumen content. For the trial, twenty-four goats were divided into four homogenous clusters (six goats/treatment) according to their fat corrected (4%) milk yield, body weight and age and individually were fed with alfalfa hay and concentrate feeds (F/C = 50/50). The concentrate of the control group (CON) contained no microalgae, while those of the treated groups were supplemented daily with 20 (ALG20), 40 (ALG40), and 60 (ALG60) g of Schizochytrium spp./goat. The relative abundances of total Archaea, methanogens, Methanomassiliicoccales, Methanobrevibacter spp., Methanosphaera stadmanae and Methanobacterium formicicum were significantly (p &lt; 0.05) decreased in microalgae-fed goats compared to the CON ones. Moreover, a significant decline in the relative abundances of Firmicutes, Ruminococcus flavefaciens, Butyrivibrio fibrosolvents, and Neocallimastigales in the rumen particle-associated microbiota of microalgae supplemented goats were observed. In conclusion, goats’ diets supplementation with Schizochytrium spp., could be considered a sustainable nutritional strategy for methanogens inhibition in their rumen particle-associated microbiota.

A novel modelling approach to quantify the response of dairy goats to a high-concentrate diet

High-producing ruminants need high-concentrate diets to satisfy their nutrient requirements and meet performance objectives. However, such diets induce sub-acute ruminal acidosis (SARA), which will adversely affect dry matter intake and lead to lower production performance. This work develops a novel modelling approach to quantify the capacity of dairy goats to adapt to a high-concentrate diet challenge at the individual level. The animal model used was dairy goats (from Saanen or Alpine breed), and rumen pH was used as the indicator of the response. A three-step modelling procedure was developed to quantify daily scores and produce a single global index for animals’ adaptive response to the new diet. The first step summarizes the post-prandial kinetics of rumen acid status using three synthetic variables. In the second step, the effect of time on the response of goats is described, in the short and long terms. In the last step, a metric based on phase trajectories ranks goats for their resilience capacity. This modelling procedure showed a high variability among the goats in response to the new diet, highlighting in particular their daily and general strategies to buffer the effect of the diet change. Two main categories of adaptive strategies were observed: (i) acid status increased, but the goats tried to minimize its variations, and (ii) acid status oscillated between increases and decreases. Such phenotyping, alongside other behavioral, digestive, and metabolic measures, can help to determine biomarkers of goats’ capacity to adapt to diets of higher nutritive value and to increase production performance without compromising their health status. Quantifying the capacity of goats to buffer the effect of highly fermentable diets helps to better adapt feed to animals in precision livestock farming. This procedure is generic and can be adapted to any indicator of animal health and performance. In particular, several indicators can be combined to assess multi-performance, which is of major interest in the context of selection for robust animals.

Alterations in Rumen Bacterial Community and Metabolome Characteristics of Cashmere Goats in Response to Dietary Nutrient Density.

Simple SummaryDietary energy and protein play important roles in rumen fermentation. However, the impacts of dietary energy and protein on the relationships between rumen bacterial composition and ruminal metabolites were not extensively studied. In this study, we investigated the rumen fermentation status in response to different energy and protein levels, which was vital for the rumen health and resulted in the potential positive effects on the host health and production. Thereby, quantitative polymerase chain reaction analysis and 16S rRNA gene sequencing showed that the bacterial richness was significantly reduced, and the rumen bacterial composition was significantly altered with the increasing levels of dietary energy and protein. Metabolomics analysis revealed that the dominant differential metabolites were amino acids, peptides, and analogs. Moreover, high-energy and high-protein diets could enhance the ruminal antioxidative capacity by increasing the concentration of some metabolites. Correlation analysis implied that high energy and protein levels could enhance the catechol concentration by Prevotella_1 and Ruminococcus_2. This study can help to improve the dietary energy and protein use efficiency in goats.This study was conducted to investigate the impacts of dietary energy and protein on rumen bacterial composition and ruminal metabolites. A total of 12 ruminal samples were collected from Shaanbei white cashmere goats which were divided into two groups, including high-energy and high-protein (Group H; crude protein, CP: 9.37% in dry matter; metabolic energy, ME: 9.24 MJ/kg) and control (Group C; CP: 8.73%; ME: 8.60 MJ/kg) groups. Thereby, 16S rRNA gene sequencing and a quantitative polymerase chain reaction were performed to identify the rumen bacterial community. Metabolomics analysis was done to investigate the rumen metabolites and the related metabolic pathways in Groups C and H. The high-energy and high-protein diets increased the relative abundance of phylum Bacteroidetes and genera Prevotella_1 and Succiniclasticum, while decreasing the number of Proteobacteria (p < 0.05). The dominant differential metabolites were amino acids, peptides, and analogs. Tyrosine metabolism played an important role among the nine main metabolic pathways. Correlation analysis revealed that both Prevotella_1 (r = 0.608, p < 0.05) and Ruminococcus_2 (r = 0.613, p < 0.05) showed a positive correlation with catechol. Our findings revealed that the diets with high energy and protein levels in Group H significantly altered the composition of ruminal bacteria and metabolites, which can help to improve the dietary energy and protein use efficiency in goats.

Evaluation of the immunogenicity and efficacy of BCG and MTBVAC vaccines using a natural transmission model of tuberculosis

Effective vaccines against tuberculosis (TB) are needed in order to prevent TB transmission in human and animal populations. Evaluation of TB vaccines may be facilitated by using reliable animal models that mimic host pathophysiology and natural transmission of the disease as closely as possible. In this study, we evaluated the immunogenicity and efficacy of two attenuated vaccines, BCG and MTBVAC, after each was given to 17 goats (2 months old) and then exposed for 9 months to goats infected with M. caprae. In general, MTBVAC-vaccinated goats showed higher interferon-gamma release than BCG vaccinated goats in response to bovine protein purified derivative and ESAT-6/CFP-10 antigens and the response was significantly higher than that observed in the control group until challenge. All animals showed lesions consistent with TB at the end of the study. Goats that received either vaccine showed significantly lower scores for pulmonary lymph nodes and total lesions than unvaccinated controls. Both MTBVAC and BCG vaccines proved to be immunogenic and effective in reducing severity of TB pathology caused by M. caprae. Our model system of natural TB transmission may be useful for evaluating and optimizing vaccines.

Changes in Ear Postures of Kid Goats in Response to Ear Tagging

No study yet is undertaken to measure pain caused by ear tagging in kid goats using ear postures. Therefore, the purpose of this study was to elucidate the effect of ear tagging procedure on pain in black Karadi kids using ear position and frequency of ear changes. Twenty black Karadi kids, aged 10-14 days, were used in this study. Ear postures were scored using focal sampling and recorded with instantaneous time sampling to measure the duration of each ear posture. Each kid was observed separately for 6 minutes before and 6 minutes after the ear tagging process with 30 seconds intervals. A total of 24 ear posture samples were recorded from each kid. Results revealed that Ear tagging significantly increased ears backward (P&lt;0.01) and decreased ears plane (P&lt;0.001). However, no significant effect of ear tagging was found on ears forward (P&lt;0.19) and asymmetrical postures (P&lt;0.43). In addition, number of ear posture changes was significantly (P&lt;0.001) increased after ear tagging. It was concluded that observing ear postures of kids directly after painful husbandry procedures such as ear tagging is a reliable non-invasive method to assess pain caused by these painful methods and hence helps better understands animal welfare.

Intake, milk yield and grazing behaviour of strip-grazing Alpine dairy goats in response to daily pasture allowance

Grazing management has an important impact on dairy ruminants’ performance. References on the intake and milk yield of dairy goats under strip-grazing systems in temperate regions are scarce. In order to study the effect of pasture allowance on pasture intake (PI), milk yield and grazing behaviour, a trial was carried out in spring with 36 Alpine goats in mid-lactation. Three daily pasture allowances (PA=1.7, 2.6 and 3.5 kg dry matter (DM)/day, namely Low, Medium and High, respectively) were compared in a 3 × 3 Latin square design replicated six times during three successive 14-day periods. Goats individually received 268 g DM of concentrate twice daily at each milking and had access 11 h/day to pasture (from 0830 to 1600 h and from 1730 to 2100 h). Pasture intake increased with PA, and more so between Low and Medium than between Medium and High (+216 v. +101 g DM/kg DM of PA). Milk yield was lower on Low than on Medium and High (2.79 v. 3.13 kg/day), as were milk fat and protein yields. Grazing time averaged 476 min/day and was lowest on Low and greatest on Medium. Pasture intake rate was 30 g DM/h lower on Low and Medium than on High. It is concluded that under temperate conditions, when goats are supplemented with 536 g DM of concentrate and have enough access time to pasture (11 h/day), a medium pasture allowance close to 2.6 kg DM/day may be sufficient to maximise milk yield.

Changes in Ear Postures of Kid Goats in Response to Ear Tagging

No study yet is undertaken to measure pain caused by ear tagging in kid goats using ear postures. Therefore, the purpose of this study was to elucidate the effect of ear tagging procedure on pain in black Karadi kids using ear position and frequency of ear changes. Twenty black Karadi kids, aged 10-14 days, were used in this study. Ear postures were scored using focal sampling and recorded with instantaneous time sampling to measure the duration of each ear posture. Each kid was observed separately for 6 minutes before and 6 minutes after the ear tagging process with 30 seconds intervals. A total of 24 ear posture samples were recorded from each kid. Results revealed that Ear tagging significantly increased ears backward (P<0.01) and decreased ears plane (P<0.001). However, no significant effect of ear tagging was found on ears forward (P<0.19) and asymmetrical postures (P<0.43). In addition, number of ear posture changes was significantly (P<0.001) increased after ear tagging. It was concluded that observing ear postures of kids directly after painful husbandry procedures such as ear tagging is a reliable non-invasive method to assess pain caused by these painful methods and hence helps better understands animal welfare.

Selective behavior of Creole goats in response to the functional heterogeneity of native forage species in the central Monte desert, Argentina

The changes in forage availability and the physicochemical variability of plants influence the diet selection by herbivores. In this study, the foraging behavior of Creole goats was studied in terms of botanical composition of the diet, food availability and physicochemical properties of vegetation. The study was performed in a desert rangeland in the northeast (NE) Mendoza region in Argentina. Experiments with grazing goats were made in dry (winter) and wet (summer) seasons and cafeteria experiments (feeding trial) were performed during the summer. Food availability was estimated from forage species cover. Botanical composition of the goat's diet was determined by microhistological analysis of fecal samples. Morphological parts of forage species consumed by goats were sampled and analyzed to determine chemical traits (plant nutrients and secondary metabolites) in both seasons. Also, during summer, the two morphological traits of browse species stem specific density (SSD) and specific leaf area (SLA) were evaluated. In the experiments with grazing goats, diet selection was evaluated based on Ivlev's electivity index (Iˆ) and, in cafeteria experiments, preference was estimated based on the number of bites. Diet selection varied between the two seasons. Grazing goats showed differences in the patterns of diet selection related to changes in forage availability. The botanical composition of the diet had a greater (p<0.001) participation of woody species in relation to grass species in both seasons, but the herbaceous stratum was more utilized by goats during the summer according to their higher availability. Correlations between diet and availability were positive in both seasons, but not significant in summer. The models including crude protein (CP), neutral detergent fiber (NDF) and total phenols (TP) had substantial support for predicting variation in diet selection in summer and winter. In both seasons the preference increased as the concentrations of CP, NDF and TP increased, but the effect of CP was significant only in winter. Thus, goats selected supplementary food mixtures (mixed diet) and tannins were not considered dissuasive but, rather, were maintained below a certain threshold. In summer, SSD was negatively and significantly related to diet selection by grazing goats. This morphological trait allowed explaining a greater percentage of the variation in Iˆ (36%) with regard to the variation explained by the chemical variables (16%). In cafeteria experiments, in summer, the optimization of nutrient intake rate through consumption of species with low SSD values represented a best explanation for the preferences observed, whereas the hypotheses of minimization of secondary metabolites and maximization of nutrients were not able to fully explain the preferences observed in cafeteria experiments. To conclude, dietary decisions by goats in desert rangelands could be interpreted in terms of intake rate optimization and complementation of nutrients and secondary compounds, rather than by explanations involving the isolated effects of nutrient intake maximization or tannin intake minimization.

Rates of oxalic acid degradation in the rumen of sheep and goats in response to different levels of oxalic acid administration

AbstractOxalic acid is found in high concentrations in some plants consumed by ruminants and may cause renal toxicity. To determine whether exposure to oxalic acid affects the capacity of the rumen of sheep and goats to degrade the compound, 20 animals (10 sheep and 10 goats) were dosed with free oxalic acid by gelatin capsule twice daily for 3 weeks at one of five levels (0·0, 0·3, 0·6, 0·9 and 1·2 mmol/kg live weight (M) per day). Rumen samples were collected by stomach tube in the week prior to the start of dosing and in each week of the 3-week experiment. Oxalic acid degradation capacity was measured by adding uC-labelled oxalic acid to rumen fluid in vitro and capturing evolved 14CO2. Rates of degradation increased with increasing level of administration (2·30, 4·71, 6·74, 9·83 and 13·90 mmol of oxalic acid degraded per I rumen fluid per day for doses 0·0, 0·3, 0·6, 0·9 and 1·2 mmol/kg M per day, respectively; P &lt; 0·001). Rates of degradation increased during the dosing period (P &lt; 0·001) with the largest increases occurring in the 1st week of dosing. Goats showed a greater response than sheep, with a higher mean oxalic acid degradation capacity (9·04 v. 5·95 mmol of oxalic acid degraded per I rumen fluid, P &lt; 0·05). Oxalic acid administration did not influence plasma calcium concentration or cause renal function impairment as measured by plasma creatinine concentrations. The experiment demonstrated adaptation in the rumen to potential toxins in the host diet and suggests that the rumen micro-organisms of goats may have been more adapted to degrading oxalic acid than sheep.

PHYSICAL CHARACTERISTICS OF THE VOCALIZATIONS OF DOMESTIC GOAT DOESCAPRA HIRCUSIN RESPONSE TO THEIR OFFSPRING'S CRIES

ABSTRACT The vocalizations emitted by adult female domestic goats in response to their offspring's bleats were recorded, and sonograms were made and analyzed. The calls were segmented, atonal, and broad banded between 200 and 4,840 Hz. The energy was concentrated, on the average, around 1,258 Hz, a frequency close to the optimal hearing capabilities of the species. There were statistically significant individual differences for duration, number of segments, number of harmonics, peak frequency and fundamental frequency. Furthermore, using a discriminant function analysis we were able to correctly assign 76% of the calls to the individuals that emitted them. We concluded that the does have individually distinctive vocalizations, and that the physical characteristics of the bleats allow for locatability and ease of detection of the signal. Therefore, it is possible for the kids to be able to recognize and locate their mothers on the basis of auditory cues.