Intake Of Goats Research Articles

Effects of rumen-protected 5-hydroxytryptophan on circulating serotonin concentration, behaviour, and mammary gland involution in goats

The risk of acquiring new intramammary infections is high at the end of lactation, especially for the high milk-producing dairy animals. Resistance to bacterial infection increases following the completion of mammary gland involution after milking cessation. The serotonin precursor 5-hydroxytryptophan (5-HTP) could accelerate involution by increasing circulating serotonin levels, but ruminal microbes may degrade 5-HTP if orally administered to adult ruminants. It is unclear whether rumen-protected 5-HTP could effectively mediate circulating serotonin (5-hydroxytryptamine, 5-HT) and therefore accelerate mammary gland involution in ruminants. Goats were used as a model in the current study to investigate the effects of rumen-protected 5-HTP on behaviour, 5-HT metabolism, and mammary involution in ruminants. In the first experiment, 16 female Dazu black goats were assigned to one of four groups in a randomised block design. The treatments included a basal diet plus 0, 4, 20, or 100 mg/kg BW of rumen-protected 5-HTP. Serum was collected at 0, 3, 6, 12, and 24 h after offering the rumen-protected 5-HTP in the morning feed, and the behaviours were monitored. In the second experiment, 12 female Dazu black goats (Somatic cell count < 250 000) were randomly assigned to the control (basal diet) or rumen-protected 5-HTP group (basal diet plus 20 mg/kg BW). Milk or mammary secretions were manually collected aseptically on d −1, 1, 2, 3, 4, and 5 around weaning. The results depicted that rumen-protected 5-HTP supplementation elevated circulating 5-HTP and 5-hydroxyindole acetic acid concentrations, while 20 mg/kg BW of rumen-protected 5-HTP supplementation lowered the goats’ locomotive activity. A high concentration of rumen-protected 5-HTP (100 mg/kg BW) increased serum alkaline phosphatase and gamma-glutamyl transpeptidase concentrations. Moreover, oral supplementation with 20 mg/kg BW of rumen-protected 5-HTP accelerated mammary gland involution and reduced feed intake in goats after weaning. These results demonstrate that oral supplementation with rumen-protected 5-HTP influences 5-HT metabolism and accelerates mammary gland involution after milking cessation in ruminants.

Supplementation of crossbred boer goats with cottonseed meal and/or urea enhances estimated metabolizable protein intake, crude protein digestibility and nitrogen retention

This study aimed to determine feed intake, apparent digestibility, and nitrogen retention of crossbred Boer bucks supplemented with urea or cottonseed meal (CSM)when fed tropical Rhodes (Chloris gayana) grass hay (RGH) as a basal diet. Twelve eight-month-old bucks (23.9±1.1 kg live weight) were allocated to one of the four dietary treatments in a randomised block design. The treatments were 1) maize supplement (Control); or maize plus 2) urea supplement (M+U), 3) urea and CSM (M+UCSM); and (4) CSM (M+CSM). All bucks were held in individual metabolism crates for 21 days (11 days of adaptation and 10 days collection period) with ad libitum access to RGH and fresh drinking water in addition to the supplements. A one-way ANOVA and Duncan’s multiple range tests were used to test for differences between means at a significance level of P &lt; 0.05. Results indicated higher feed intake, apparent digestibility of crude protein and digestible nutrient intake in goats supplemented with M+CSM and M+UCSM, but not M+U alone. Supplementation with M+CSM increased nitrogen retention by 300%. Supplementation with M+UCSM and M+CSM increased the total feed intake of Boer goats on tropical grass hay by 13 and 20%, respectively. Supplementation with M+U, M+UCSM, and M+CSM improved the apparent digestibility of crude protein by 9.7, 15.7 and 15.1%, respectively. It can be concluded that total feed intake and nutrient digestibility was increased on growing Boer goats fed RGH as a basal diet supplemented with true protein from CSM or a mixture of true protein and rumen degradable protein from urea.

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

Simple SummaryGrazing/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.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/Kg0.75), 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 (R2 = 97.51, p = 0.0001), while the DMI was affected by in vitro DM digestibility and flavonoids (R2 = 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.

Effects of Replacing Grass with Foliage on Growth Rate and Feed Intake in Goats-A Systematic Review and Meta-Analysis.

Simple SummaryGoats are important as food sources and livelihood in several areas of the world, mainly in low-income countries. Free-range browsing is common, but to increase productivity and improve health, supplemental or complete feeding is increasing. Ruminant feeding has often been using grasses, but as goats are browsers, they may benefit from including foliage in the diet. This systematic review and meta-analysis focuses on the effect of including foliage in goat diets. The results show that foliage was often more nutrient-rich and increased dry matter intake as well as average daily weight gain in goats.Small ruminants such as goats have a higher preference for browse species than cattle and sheep. In a meta-analysis of 42 papers describing 117 experimental treatments found by a search performed in June 2021 in PubMed and Web of Knowledge, we examined the general effect of including foliage in the diet of goats, replacing grasses, on dry matter intake and average daily weight gain. The inclusion requirement for a paper was that it described a controlled trial with a control diet of grass and with grass replaced by foliage in the experimental diet. Publication bias was estimated by calculating the Fail-safe n. Random effects analyses were conducted, using effect size calculated as Hedges’ d. The results showed that inclusion of foliage increased feed intake (Hedges’ d = 1.350, SE = 0.388) and average daily weight gain (Hedges’ d = 1.417, SE = 0.444) compared with a grass-based control. The positive effect of foliage inclusion on dry matter intake was associated with lower neutral detergent fiber (NDF) and higher crude protein (CP) in the foliage than in the grass it replaced. The positive effect on average daily weight gain was associated with higher CP concentration in the foliage than in grass. Foliage inclusion level showed a quadratic relationship with dry matter intake, with maximum dry matter intake achieved at a level of 50–60%. There was wide variation between the studies reviewed, and this variation was not reduced by subgroup analysis based on different kinds of foliage. In conclusion, the addition of foliage to goat diets can increase feed intake and daily weight gain, as an effect of the dietary preferences of goats and of generally higher nutritional value in foliage species compared with natural/semi-natural grass species.

NUTRIENT INTAKE OF WEST AFRICAN DWARF GOATS FED DIETARY MODELS OF ENSILED CASSAVA PEEL MEAL FORTIFIED WITH CALCIUM-PHOSPHORUS SALT

Objective: This study was conducted to determine nutrient intake of growing West African Dwarf goats fed different dietary models of ensiled cassava peel meal fortified with Calcium-Phosphorus salt mix. Methods: Twenty (20) growing West African Dwarf female goats aged 6–8 months with an initial weight of 8.2 kg ± 0.25 were used for the study. They were randomly allotted to four dietary treatments with five goats per treatment in a completely randomized design. The dietary treatments were Diet 1 (block), Diet 2 (crunchy), Diet 3 (pellet), and Diet 4 (mash). Results: Results obtained indicated that dry matter intake ranged from 466.18 g/d to 575.53 g/day with significantly (p&lt;0.05) higher value in pellet model while crude protein intake was higher in mash model than other treatments. Ether extract and crude fiber intake values were higher 40.13 g/day and 148.08 g/day in pellet feed model. Ash intake ranged from 61.32 g/day to 95.86 g/day. Block and crunchy models had significantly (p&lt;0.05) higher value for ash intake while values obtained for nitrogen-free extract intake was also higher (p&lt;0.05) in pellet model 22.62 g/day than other models. Values of fiber fractions intake obtained were significantly (p&lt;0.05) influenced by dietary models with higher values for neutral detergent fiber, acid detergent fiber and hemicellulose in mash while acid detergent lignin was significantly (p&lt;0.05) for pellet model. Conclusion: It can be concluded that supplementing goat diets with different dietary models of ensiled cassava peel meal fortified with Calcium- Phosphorus salt mix can boost intake of goats for better productive performance and productivity.

Growth Performance and Feed Intake of Goats Fed Garlic (Allium sativum) Supplemented Diets

Growth Performance and Feed Intake of Goats Fed Garlic (Allium sativum) Supplemented Diets

PSX-23 Predicting feedstuff associative effects in goats

Abstract The objective was to develop means of predicting effects of supplementation on forage and total ME intake in goats. A database of treatment mean observations from the literature currently has 529 individual animal observations with ad libitum intake from 24 studies. Essential data were supplement and forage OM digestibility without supplementation or sufficient information for estimation, total diet OM digestibility, forage and supplement CP concentration and OM intake, and BW. Intake of ME was assumed 15.104 MJ/kg digested OM. For observations with supplementation, forage ME intake was the difference between total and supplement ME intake. The original database had 134 observations, although 24 were omitted because of questionable values and(or) unlikely estimates. Forage averaged 9.4 MJ/kg DM of ME (SD=1.77, 4.6–12.6), 59.1% OM digestibility without supplementation (SD=8.67, 42.9–77.1; AOMDIGFOR), and 8.1% CP (SD=3.72, 2.1–17.1) (PTCPFOR), and supplement was 12.3 MJ/kg ME (SD=1.38, 7.1–15.1) and 28.4% CP (SD=41.5, 0–288). Forage ME intake (MEIMBWFOR, kJ/kg BW0.75) was regressed against supplement ME intake (MEIMBWSUP, kJ/kg BW0.75), with inclusion of other variables tested. The equation explaining most variation (R2=0.77) was 155.9 ± 135.75 – (0.5403±0.04381 × MEIMBWSUP) – (41.0063±20.71841 × PTCPFOR) + (5.3497±2.31608 × AOMDIGFOR) + (0.74056±0.345002 × PTCPFOR × AOMDIGFOR), with P values of 0.253, &amp;lt; 0.001, 0.050, 0.023, and 0.034, respectively. The mean difference between observed and predicted MEIMBWFOR (379±15.0 and 382±12.8, respectively) was -3±7.4, with minimum and maximum values of -181 and 167, respectively. The equation for the regression of residual MEIMBWFOR (observed – predicted) against predicted values was -10±22.3 + (0.018±0.0553 × predicted MEIMBWFOR), with the intercept and slope not different from 0 (P = 0.670 and 0.739, respectively). Equations describing associative effects can be used to predict the quantity of a particular supplement with a given forage necessary to meet nutrient requirements of goats in specific production settings.

Predicting the growth and feed intake of Boer goats in a feedlot system

This research sought to develop a mathematical model to predict the growth and feed intake of Boer goat kids destined for slaughter. Data were collected from castrated kids that were housed in individual pens and fed diets that varied in energy content (11.3, 12.0, and 12.7 MJ metabolizable energy (ME)/kg feed). Growth and feed intake were monitored weekly for 20 weeks, from the time that the kids weighed 22.2 ± 3.5 kg until they were slaughtered at 48.3 ± 0.8 kg. The linear equation (bodyweight = 0.202 age – 5.241 (R2 = 0.84)) was found to predict the growth of kids between 126 and 266 days old. Correlations between expressions of intake and bodyweight were evaluated, cumulative feed intake and bodyweight being most highly correlated (r = 0.93). Linear models were developed to predict cumulative feed intake from bodyweight for goats fed each diet. Regression coefficients were compared between diets, with the slope of the equation for goats on the low energy diet (6.74 ± 0.25) being greater than that of the medium (5.80 ± 0.23) and high energy diets (5.82 ± 0.23). This indicates that goats on the medium and high energy diets gained weight more efficiently than those on the low energy diet. The results from this study can be used by goat producers to predict the growth and intake of goats and determine the ideal feedlot finishing period for optimal productivity.______________________________________________________________________________________Keywords: cumulative intake, dietary energy, modelling

Effects of ethyl ester supplementation to forage on short-term dry matter intake and preference by goats

ABSTRACTIn whole-crop maize silages with atypical smell and decreased acceptance by ruminants, high concentrations of the volatile organic compounds ethyl acetate (EA) and ethyl lactate (EL) were detected. The aim of this study was to evaluate the impact of different concentrations of ethyl esters added to forage on preference and short-term feed intake of goats. In the first of three trials, whole-crop maize silage was supplemented with different concentrations of EA and EL and then vacuum-stored before use. Forages sampled during the preference trial showed a good recovery of EL with a high accordance of target (naturally formed + supplemented) and analysed concentrations. Supplemented EA was not recovered, making transient storage of substrates before use in feeding trials equivocal. However, four treatments with different concentrations of EL (approximately 330, 560, 920 and 1300 mg/kg dry matter (DM)) were used for the preference trial. In Trials 2 and 3, EA and EL (with and without ethanol, respectively) were added to grass hay directly before offering the feed, each in concentrations of 0, 600 and 1200 mg/kg DM to have six treatments each. In all trials, each possible combination of treatments was offered to Saanen-type wethers (n = 10, Trial 1; n = 5, Trials 2 and 3) as free choice in preference trials. In Trial 1, there was only a weak impact of EL on preference behaviour as goats avoided medium EL concentrations, but did not avoid silages with higher concentrations. In Trials 2 and 3, there was no influence of added volatiles on short-term DM intake and preference at all. It can be concluded that it is unlikely that ethyl esters as single substance or in combination with ethanol affect preference behaviour and feed intake of ruminants. Possibly a combination or still unidentified fermentation products cause avoidance instead of a single compound.

Influencia de fuentes y concentraciones de saborizantes sobre el consumo de forraje en caprinos

The behavior of caprine to taste stimuli affects the consumption of dry matter (MS), and the inclusion of sensorial stimulators can increase productivity. The objective of this experiment was to evaluate different sources and concentrations of flavoring on forage intake in goats. The research was developed at the Dairy Cattle Experimental Station “Alfredo Volio Mata” of the University of Costa Rica, in Ochomogo, Cartago, Costa Rica during October 2015. A coffee-shop test was used in a block crossover model. Pennisetum purpureum cv King grass mixed with four flavors (acid, bitter, sweet and salty) in five different concentrations (0, 0.25, 0.5, 0.75 and 1.0%) was supplied to a group of goats. Goats showed the greater preference for forage mixed with a bitter flavor, and less preference for sweet and salty flavors. The forage intake on a dry basis showed by the animals when the acid flavor was applied, was 0.977 kg/d, when the sweet and salty flavorings were used the intake was 0.855 and 0.822 kg/d, respectively. These differences were significant. The goats consumed 68.28% of the amount of offered forage when the bitter flavor was used, but only consumed 56.43% of what was offered when the forage was acidified. When comparing the inclusion of any flavor with respect to an unflavored control treatment, no significant differences were observed in the consumption of dry matter or the degree of acceptance. No effect on dry matter consumption or acceptance percentage was observed when different concentrations of flavorings were used. The interaction between flavor and flavor concentration did not generate significant differences in any of the evaluated parameters.

Consumption of Goats' Milk Protects Mice From Carbon Tetrachloride-Induced Acute Hepatic Injury and Improves the Associated Gut Microbiota Imbalance.

Drugs used to treat liver diseases have serious side effects; it is important to search for safe functional foods with hepatoprotective functions and few side effects. In this study, potential hepatoprotective effects of goats’ milk and cows’ milk on mice with CCl4-induced acute hepatic injury were evaluated. We also elucidated the role of goats’ and cows’ milk on the regulation of CCl4-induced gut microbiota imbalance. In mice with liver damage induced by CCl4, administration of goats’ milk for 7 days prior to injection of CCl4 had beneficial effects on the indicators of liver damage within 1 day: the area of liver necrosis was small; activity of alanine transaminase (ALT) and aspartate transaminase (AST) and expression of the genes CYP2E1 and TNF-α were lower than that of model group of mice. By 7 days after CCl4 injection, there were no significant differences in liver damage indicators (ALT, AST, malondialdehyde, superoxide dismutase, and glutathione) between the goats’ milk group, which continued to receive goats’ milk, and the untreated control group of mice showing that goats’ milk continued to protect against liver damage. Throughout the entire experiment, the community of gut microbes from mice in the goats’ milk treatment was more similar to the untreated control group than to the cows’ milk group and the model group, indicating that intake of goats’ milk prior and post-CCl4 injection effectively prevented and alleviated the intestinal microbial disorder that caused by CCl4 in mice. Our research suggests that goats’ milk could be developed as a potential functional food to prevent/protect against liver injury.

Ensiled sugar beets as dietary component and their effect on preference and dry matter intake by goats

ABSTRACTThis study examines the influence of ensiled sugar beets (Beta vulgaris ssp. vulgaris) on preference and short-time dry matter (DM) intake of goats. Whole sugar beets were ensiled either without any silage additive (sugar beet silage (SBS)) or with a chemical additive (6 l/t) containing 85% formic and propionic acids (treated sugar beet silage (TBS)) and were chopped after ensiling. The influence of different proportions of SBS (0%, 6.25%, 12.5%, 18.75% and 25% of dietary DM) and TBS (0%, 5%, 10%, 15% and 20% of DM) in partial mixed rations on short-time DM intake by goats (adult Saanen type wethers; n = 10) was studied in two separate, independent trials. Preference behaviour was investigated by offering the goats two different experimental diets per day and offer each possible combination of them (n = 10) once throughout the trial. On this basis, the mean DM intake (within 30 min and 3 h) of each experimental diet was determined. Both sugar beet silages showed good fermentation quality with low pH. By using the chemical silage additive, the production of ethanol was reduced and considerable amounts of sugar were preserved. In the short-term preference experiment, increasing concentrations of sugar beet silage in the ration increased DM intake (p < 0.05) in a linear way with a strong preference for those diets containing high amounts of sugar beet silage. Initial DM intake after 30 min was 4–5 fold increased for diets containing the highest beet concentration. It is assumed that the preference was positively influenced by sugar and sweet taste or the associated higher concentration of metabolisable energy.

Effect of rumen-protected conjugated linoleic acid on ruminal biohydrogenation and transfer of fatty acids to milk in dairy goats

The objective of the study was to evaluate ruminal biohydrogenation (BH) and apparent transfer of long-chain (FA) from duodenum into milk in dairy goats fed Ca salts of palm oil (CaS, 45g/d) or lipid-encapsulated conjugated linoleic acids (LE-CLA, 45g/d providing 4.5g trans-10, cis-12 C18:2/d and 4.5g cis-9, trans-11 C18:2/d). Twelve lactating multiparous dairy Saanen or Alpine goats (65±3 days in milk) were randomly allocated to two experimental treatments (CaS vs LE-CLA) for a 3 wks experiment. The goats were fitted with a ruminal cannula and a T-type duodenal cannula for the measurement of duodenal flow by supplying 2.4g of Cr2O3/d through the rumen cannula during 3 wks: the first one was for reaching steady-state concentration of this marker in the digestive tract, the second wk was for measuring the daily flow of faecal chrome and nutrient faecal digestibility, and the third wk was for the duodenal sampling. LE-CLA did not affect intake, duodenal flow and apparent ruminal digestibility of DM, OM, NDF and starch. Compared to CaS, LE-CLA tended to decrease total digestibility of DM and NDF whereas total digestibility of starch was not affect by dietary treatments. The duodenal flow of FA was higher than FA intake in goats fed CaS or LE-CLA. LE-CLA increased the duodenal flows of C18:2 trans-10, cis-12, and C18:2 cis-9, trans-11, leading to a calculated 16% protection from BH for both FA. The LE-CLA treatment tended to decrease the duodenal flows of C18:2 cis-9, trans-12 and C18:2 trans-9, cis-12. The ruminal biohydrogenation of C18:1 cis-9, C18:2 cis-9, cis-12, and C18:3 cis-9, cis-12, cis-15 was not affected by the LE-CLA treatment. Average apparent transfer between the duodenum and milk fat was 22%, 44%, 36% and 22% for C18:2 trans-10, cis-12, C18:2 cis-9, trans-11+ C18:1 trans-11, C18:2 cis-9, cis-12 and C18:3 cis-9, cis-12, cis-15, respectively. Apparent transfer efficiency of long-chain FA was not affected by LE-CLA treatment.

Modelos não lineares para descrever o consumo, deposição de nutrientes no corpo e crescimento de cabritos Saanen x Alpina

The objective of this study was to evaluate nutrient intake in goats’ milk-fed goats varying in fat concentration (24.2, 34.4, 44.3, 65.6 and 82.1 g.kg-1 MS) to study Its effect on feed performance and feed conversion, during lactation and post-suckling, in a completely randomized design in a factorial scheme with 12 replicates per liquid diet initially. The experimental period began on the seventh day of life, with 60 Saanen and Alpina goats confined in individual metabolism cages, receiving 1.5 L / Milk / day divided into two meals at 08:00 and 15:00 until 15 days of life; From day 16 to day 52 of life was offered 2L / Milk in two meals, from day 53 and until day 67 of life the animals began to receive 1L / Milk in the afternoon; And from day 37 to day 195 of life Tifton-85 (Cynodon dactylon) ad libitum grass and 10 g/kg PV of concentrated feed were supplied for each animal. A slaughter reference was made to the seven days of life and four slaughterings during the experiment: 37, 67, 142 and 195 days of life. All statistical procedures were programmed in the SAS (9.0) through PROC NLIN adopting 0.05% probability for the Type I error. There was a difference (P<0.001) in the consumption of dry matter, protein, fat and non-fibrous carbohydrates In the lactation phase. There was an effect (P<0.001) for the deposition of crude fat, crude protein and mineral matter in the animal body during the lactation phase. However, after the substitution by the solid diet, the reduction in this difference is verified in the medium term.

The Effect of Supplementing Air-Dried Moringa stenopetala Leaf to Natural Grass Hay on Feed Intake and Growth Performances of Arsi-Bale Goats

The most constraining factor in goat production in the tropics is underfeeding mainly attributed to limitations of feed both in quantity and quality. This study was conducted to assess the effect of supplementing different levels of air-dried Moringa stenopetala leaf (MSL) as a protein source on nutrient intake and growth performances of Arsi-Bale male goats. A total of 24 yearling goats with average initial body weight of 13.6 ± 0.25 kg were used in the study. The goats were blocked by live weight into four groups (n = 6 per group) and the groups were then randomly allocated into four supplemented treatments. All goats received a basal diet of natural grass hay ad libitum and 340 g/head/day concentrate. The treatments were the control diet with no supplementation (Treatment 1, T1) and diets supplemented with MSL at a rate of 120 g/head/day (Treatment 2, T2), 170 g/head/day (Treatment 3, T3) and 220 g/head/day (Treatment 4, T4). The duration of the experiment was 75 days. The results indicated that the average daily feed intake was (p &lt; 0.001) higher in goats supplemented with T3 and T4 diets. The total dry matter, organic matter, and crude protein intakes of goats fed with T3 and T4 supplementations were (p &lt; 0.001) also higher than those reared in T1 and T2 diets. Goats reared in T3 and T4 diets had lower (p &lt; 0.05) feed conversion ratio than those fed with T1 and T2 diets. The final body weight in goats reared in T3 and T4 diets was 18.2 kg and 18.5 kg, respectively, being (p &lt; 0.05) higher than those of T1 (15.8 kg) and T2 (16.3 kg). The average daily weight gain in goats fed with T3 and T4 diets was 111 and 114 g/goat/day, respectively, which was (p &lt; 0.05) higher than those reared in the control (T1) (54.0 g/goat/day) and T2 (58.1 g/goat/day) diets. It can thus be concluded that goats reared at high level of MSL supplementation (T3 and T4) had better nutrient intake, feed conversion efficiency and growth performances, suggesting its potential as a good protein supplement to natural grass hay at the farmer’s management level.

Mediterranean Shrub Diversity and its Effect on Food Intake in Goats

Mediterranean ecosystem offers a variety of shrubs that were over long periods of time involved in the evolution of complex plant-animal interactions. Biochemical components of these plants enter different metabolic pathways after digestion and absorption, resulting in development of dietary preferences in browsing animals. Herbivores in general were found to perform better when grazing in a mixed plant community composed of diverse species, and show preferential feeding behavioure for mixed vs single species diet. Our findings demonstrate an asymptotic relationship among Mediterranean shrubs species diversity and their voluntary intake by goats. Shrub biomass intake showed linear increase when number of different shrubs in diet increased from one to three. However, goats did not further increase intake when the number of shrub species increased from four to eight. As the number of shrub species offered increased, goats exhibited more preferential feeding behaviour for Quercus pubescens, Fraxinus ornus, Rubus heteromorphus and Arbutus unedo and decreased the intake of Hedera helix, Juniperus oxycedrus and Helichrysum italicum. This asymptotic relationship indicates that the maintenance of plant species richness in Mediterranean shrublands can overall benefit domestic goat farming, goat’s productive performance, and the conservation of plant biodiversity.

Adaptive responses of calcium and phosphate homeostasis in goats to low nitrogen intake: renal aspects

In a previous study, in goats, we showed that apart from variations in dietary calcium (Ca) and phosphorus intake, also low dietary nitrogen (N) intake altered plasma concentrations of hormones, which regulate Ca and phosphate (Pi ) homeostasis. These hormonal responses in goats were in accordance with findings in monogastric animals and humans with low protein intake. In the aforementioned studies, alterations of electrolyte transport in the kidneys were also observed. However, whether renal electrolyte transport in goats is also involved in the adaptation of Ca and Pi homeostasis to low N intake remains unknown. Thus, the aim of the present study was to investigate whether in addition to the hormonal changes, as observed in our former study, renal Ca transport and renal Pi transport were also altered by low N intake in goats. Therefore, in kidney samples from the goats used in our former study, the protein expression of Ca and Pi transporters and of related regulatory proteins was examined. Furthermore, the uptake of Pi into isolated brush border membrane vesicles (BBMV) was detected. The results showed that the protein amount of the renal sodium-dependent Pi transporter NaPi IIa was elevated, and concomitantly, protein expression of its upstream regulators, the parathyroid hormone receptor and the extracellular signal-regulated kinases 1 and 2 was decreased. However, Pi uptake into renal BBMV was not enhanced. Furthermore, protein expression of the renal Ca channel, the transient receptor potential cation channel subfamily V member 5 (TRPV5) and of the vitamin D receptor was not influenced by dietary N reduction. We conclude that regulation of renal Pi transporter expression in goats is involved in the adaptation of electrolyte homeostasis to low N intake.

Evaluating the performance, carcass traits and conjugated linoleic acid content in muscle and adipose tissues of Black Bengal goats fed soybean oil and sunflower oil

An experiment was conducted to investigate the feeding of soybean oil (SOY) and sunflower oil (SUN) on performance, carcass traits and fatty acid (FA) composition, including conjugated linoleic acids (CLA) in meat of Black Bengal goats. Eighteen growing goats (initial body weight (BW) of 11.1±0.49kg and 9–12 months of age) were equally allotted into 3 groups (control, SOY and SUN) in a randomized complete block design (blocked according to initial BW). Goats were fed concentrate mixtures with similar nitrogen and calculated metabolizable energy content with added vegetable oils (SOY or SUN) at 45g/kg dietary dry matter or without oil (control), and berseem hay (60:40). A metabolic trial was conducted after 105 days of feeding, and carcass traits and fatty acid composition of longissimus dorsi muscle and subcutaneous adipose tissues were determined at 122 days of feeding. Oil supplementation did not affect (P>0.05) average daily gains and feed intake in goats. Digestibilities of nutrients except ether extract (EE), and intake, excretion and balance of nitrogen were also similar (P>0.05) among dietary treatments. Digestibility of EE in goats receiving both plant oils was higher (P<0.01) than control. Feeding of oils did not affect (P>0.05) carcass traits, and percentages of protein, fat and ash in muscle. While supplementing oils did not change (P>0.05) the proportion of total saturated FA, they lowered several medium-chain FA in muscle and adipose tissues. However, the proportion of total polyunsaturated FA (PUFA; P<0.001) and CLA cis-9, trans-11 (P<0.001) in these tissues were highest in SUN, followed by SOY, and control. Oils had no effect (P>0.05) on concentrations of serum glucose, cholesterol and protein, but increased (P<0.05) serum triglyceride concentration compared with control. In conclusion, feeding of SOY and SUN at a concentration of 45g/kg of total diets did not affect digestibility and performance, but increased the PUFA and CLA content in muscle and adipose tissues in Black Bengal goats with the greatest effect noted for SUN.

Foraging behaviour and diet selection of free-ranging sheep and goats in the Negev Desert, Israel

SUMMARYThe foraging behaviour and dietary selection of free-ranging Awassi sheep and Negev goats when shepherded in the Negev Desert was determined. Measurements were made for 9 weeks (W1–W9) from the beginning of February, following winter rains and emergence of annual plants, to the end of March, after the herbaceous vegetation dried up. Since sheep are grazers and goats are intermediate feeders, it was predicted that goats would browse more and consume proportionately more browse than sheep. These predictions were only partially supported. In fact, the foraging pattern was similar between sheep and goats (Mantel test, P&lt;0·05) until W8 and only towards the end, at W9, did patterns differ significantly (Mantel test, P=0·214) between these two ruminants. There was no difference (P=0·575) between sheep and goats in foraging; however, a period effect was found (P&lt;0·001). In February (W2), sheep and goats grazed 0·69 and 0·71 of the time allotted for foraging and neither species browsed. Browsing commenced only at the beginning of March (W4), when goats browsed 0·08 of the time and sheep 0·07 of the allotted time for foraging. The proportion of time spent browsing increased at the end of March (W9) when annuals disappeared, but the total time spent foraging decreased: goats browsed 0·29 and grazed 0·25, while sheep browsed 0·19 and grazed 0·26 of the time allotted for foraging. Goats increased the proportion of browse consumed gradually throughout the season, whereas sheep maintained a relatively higher proportion of herbaceous plants and only in late March (W8), at which time very little herbaceous plants were available, shifted abruptly to consume mainly browse. In W8, browse composed 0·85 of the dry matter (DM) intake in goats and 0·62 of the DM intake in sheep. A simultaneous analysis of foraging time allocation and relative diet composition revealed that both small ruminants were more efficient in consuming browse than herbaceous plants, more so in goats than sheep. It was concluded that vegetation availability and foraging habits affected dietary selection. Both sheep and goats only grazed when herbaceous plants were abundantly available; differences between ruminant species were apparent when herbaceous plants became scarcer, at which time goats browsed more and consumed proportionately more browse than sheep. The results contribute to better understanding of feeding behaviour and dietary selection of sheep and goats under natural desert pastures and could be useful in the management of mixed flocks.

The preference for water nipples vs. water bowls in dairy goats

BackgroundPrevious studies have reported that the design of the water dispensers can influence the water intake in farm animals. Horses and dairy cows seem to prefer to drink from an open surface whereas sheep and pigs apparently prefer water nipples, probably because of the worse water quality in water bowls. The aim of the present study was to examine the preference of dairy goats for water nipples or water bowls.MethodsIn each of the two experiments (exp. 1, dry goats, exp. 2 lactating goats), 42 dairy goats were allotted into 6 groups of 7 goats. In period 1, the goats had access to a water nipple. In period 2, they had access to a water bowl and in period 3 (preference test) they had access to both a water nipple and a water bowl. Water usage and wastage was recorded and water intake (water usage - water wastage) was calculated for each group for the two last days of each period. In experiment 2, water samples from each dispenser were analyzed for heterotrophy germs at 22°C, Escherichia coli and turbidity.ResultsWater usage was higher from water nipples than from water bowls both in experiment 1 (dry goats) and experiment 2 (lactating goats). There was however, no difference in water intake from water nipples and water bowls. In the preference test (period 3), the water intake tended to be higher from the water nipple than from the water bowl both for the dry goats (exp. 1) and lactating goats (exp. 2). Especially for the dry goats, the differences between groups were large. Turbidity and heterotrophy germs were much higher in the samples from the water bowls than from the water nipples.Water wastage from the water bowls was negligible compared to the water nipples. From the water nipples the water wastage was 30% and 23% of water usage for the dry and lactating goats respectively.ConclusionsWe conclude that type of water dispenser (nipple or bowl) was probably of minor importance for water intake in goats, but water bowls had a lower water quality.