• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.538-546
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• 2008

Large-type goats eating dry forage secreted large volumes of saliva which resulted in the loss of $NaHCO_3$ from the blood and decreased plasma volume (hypovolemia). This research investigated whether or not the loss of $NaHCO_3$ from the blood and hypovolemia brought about by dry forage feeding actually depresses feed intake in large-type goats under free drinking conditions. The present experiment consisted of three treatments (NI, ASI, MI). All treatments in this experiment were carried out under free drinking conditions. In the NI control (NI), a solution was not infused. In the ASI treatment, i.v. infusion of artificial saliva was initiated 2 h before feeding and was continued for a total of 3 h concluding 1 h after the commencement of the feeding perod. In the MI treatment, mannitol solution was infused to replenish only water lost from the blood in the form of saliva. The hematocrit and plasma total protein concentrations during feeding in the NI control were observed to be higher than pre-feeding levels. This indicated that dry forage feeding-induced hypovolemia was caused by the accelerated secretion of saliva during the initial stages of feeding in freely drinking large-type goats. Increases in hematocrit and plasma total protein concentrations due to dry forage feeding were significantly suppressed by the ASI treatment. While hematocrit during feeding in the MI treatment was significantly lower than the NI control, plasma total protein concentrations were not different. From these results, it is clear that the MI treatment was less effective than the ASI treatment in mitigating the decreases in plasma volume brought about by dry forage feeding. This indicates that plasma volume increased during dry forage feeding in the ASI treatment which inhibited production of angiotensin II in the blood. The ASI treatment lessened the levels of suppression on dry forage feeding, but the MI treatment had no effect on it under free drinking conditions. The results indicate that despite the free drinking conditions, increases in saliva secretion during the initial stages of dry forage feeding in large-type goats caused $NaHCO_3$ to be lost from the blood into the rumen which in turn caused a decrease in circulating plasma volume and resulted in activation of the renin-angiotensin system and thus feeding was suppressed.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1182-1189
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• 2007

An intracerebroventricular (ICV) infusion of somatostatin 1-28 (SRIF) was used as a thirst-controlling peptide antagonist to investigate whether or not thirst-controlling peptides are involved in the significant decrease in feed intake during the initial stages of feeding large-type goats on dry forage. A continuous ICV infusion of SRIF was conducted at a small dose of $4{\mu}g$ ml/h for 27 h from day 1 to day 2. Goats (n = 5) were fed roughly crushed alfalfa hay cubes for 2 h twice daily and water was given ad libitum. Feed intake was measured during ICV infusion of artificial cerebrospinal fluid (ACSF) and SRIF. The feed intake during SRIF infusion increased significantly compared to that during ACSF infusion. In comparison to the ACSF treatment, plasma osmolality during the SRIF treatment significantly decreased during the first half of the 2 h feeding period. The factor causing the decrease in plasma osmolality during the ICV infusion of SRIF was a decrease in plasma Na, K, Cl, and Mg concentrations. In comparison to the ACSF infusion treatment, parotid saliva secretion volumes during the 2 h feeding period in the SRIF infusion treatment were significantly larger. While there was no significant difference in cumulative water intake (thirst levels) between the SRIF and the ACSF treatments upon conclusion of the 2 h feeding period, based on the plasma osmolality results it is thought that thirst level increases brought about by alfalfa hay cube feeding in the first half of the feeding period were reduced. It is thought that the somatostatin-induced increases in feed intake during the 2 h feeding period in the present experiment were caused by decreases in plasma osmolality brought about by the somatostatin infusion. As a result, it is suggested that the significant decrease in feed intake during the initial stages of feeding in large-type goats given roughly crushed alfalfa hay cubes, was due to the actions of thirst-controlling peptides.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.502-514
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• 2012

When ruminants consume dry forage, they also drink large volumes of water. The objective of this study was to clarify which factor produced when feed boluses enter the rumen is mainly responsible for the marked increase in water intake in the second hour of the 2 h feeding period in large-type goats fed on dry forage for 2 h twice daily. Six large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 2 to 6 years, weighing $85.1{\pm}4.89kg$) were used in two experiments. In experiment 1, the water deprivation (WD) control and the water availability (WA) treatment were conducted to compare changes in water intake during and after dry forage feeding. In experiment 2, a normal feeding conditions (NFC) control and a feed bolus removal (FBR) treatment were carried out to investigate whether decrease in circulating plasma volume or increase in plasma osmolality is mainly responsible for the marked increase in water intake in the second hour of the 2 h feeding period. The results of experiment 1 showed that in the WA treatment, small amounts of water were consumed during the first hour of feeding while the majority of water intake was observed during the second hour of the 2 h feeding period. Therefore, the amounts of water consumed in the second hour of the 2 h feeding period accounted for 82.8% of the total water intake. The results of experiment 2 indicated that in comparison with the NFC control, decrease in plasma volume in the FBR treatment, which was indicated by increase in hematocrit and plasma total protein concentrations, was higher (p<0.05) in the second hour of the 2 h feeding period. However, plasma osmolality in the FBR treatment was lower (p<0.05) than compared to the NFC control from 30 min after the start of feeding. Therefore, thirst level in the FBR treatment was 82.7% less (p<0.01) compared with that in the NFC control upon conclusion of the 30 min drinking period. The results of the study indicate that the increased plasma osmolality in the second hour of the 2 h feeding period is the main physiological stimulating factor of water intake during and after dry forage feeding in large-type goats.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.341-352
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• 2012

In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to determine whether or not marked decreases in dry forage intake after 40 min of feeding are mainly caused by the two factors, that is, ruminal distension and increased plasma osmolality induced thirst produced by dry forage feeding. Six large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 2 to 6 years, weighing $85.1{\pm}4.89kg$) were used in two experiments. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 am during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, saliva lost via the esophageal fistula was replenished by an intraruminal infusion of artificial parotid saliva (RIAPS) in sham feeding conditions (SFC) control, and the treatment was maintained under normal feeding conditions (NFC). In experiment 2, a RIAPS and non-insertion of a balloon (RIAPS-NB) control was conducted in the same manner as the SFC control of experiment 1. The intraruminal infusion of hypertonic solution and insertion of a balloon (RIHS-IB) treatment was carried out simultaneously to reproduce the effects of changing salt content and ruminal distension due to feed entering the rumen. The results of experiment 1 showed that due to the effects of multiple dry forage suppressing factors when feed boluses entered the rumen, eating rates in the NFC treatment decreased (p<0.05) after 40 min of feeding and cumulative dry forage intake for the 2 h feeding period reduced to 43.8% of the SFC control (p<0.01). The results of experiment 2 indicated that due to the two suppressing factors of ruminal distension and increased plasma osmolality induced thirst, eating rates in the RIHS-IB treatment were, as observed under NFC, reduced (p<0.05) and cumulative dry forage intake for the 2 h feeding period decreased to 34.0% of the RIAPS-NB control (p<0.01). The combined effects of ruminal distension and increased plasma osmolality accounted for 77.5% of the suppression of dry forage intake 40 min after the start of dry forage feeding. The results indicate that ruminal distension and increased plasma osmolality induced thirst are the main factors in the suppression of dry forage intake in large-type goats.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.159-169
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• 2016

The goats raised in the barn are usually fed on fresh grass. As dry forage can be stored for long periods in large amounts, dry forage feeding makes it possible to feed large numbers of goats in barns. This review explains the physiological factors involved in suppressing dry forage intake and the cause of drinking following dry forage feeding. Ruminants consume an enormous amount of dry forage in a short time. Eating rates of dry forage rapidly decreased in the first 40 min of feeding and subsequently declined gradually to low states in the remaining time of the feeding period. Saliva in large-type goats is secreted in large volume during the first hour after the commencement of dry forage feeding. It was elucidated that the marked suppression of dry forage intake during the first hour was caused by a feeding-induced hypovolemia and the loss of $NaHCO_3$ due to excessive salivation during the initial stages of dry forage feeding. On the other hand, it was indicated that the marked decrease in feed intake observed in the second hour of the 2 h feeding period was related to ruminal distension caused by the feed consumed and the copious amount of saliva secreted during dry forage feeding. In addition, results indicate that the marked decreases in dry forage intake after 40 min of feeding are caused by increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding. After 40 min of the 2 h dry forage feeding period, the feed salt content is absorbed into the rumen and plasma osmolality increases. The combined effects of ruminal distension and increased plasma osmolality accounted for 77.6% of the suppression of dry forage intake 40 min after the start of dry forage feeding. The results indicate that ruminal distension and increased plasma osmolality are the main physiological factors in suppression of dry forage intake in large-type goats. There was very little drinking behavior observed during the first hour of the 2 h feeding period most water consumption occurring in the second hour. The cause of this thirst sensation during the second hour of dry forage feeding period was not hypovolemia brought about by excessive salivation, but rather increases in plasma osmolality due to the ruminal absorption of salt from the consumed feed. This suggests the water intake following dry forage feeding is determined by the level of salt content in the feed.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1174-1183
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• 2010

In goats fed on dry forage twice a day, an esophageal fistula was used to investigate the physiological factors present in the marked suppression of dry forage intake that occurs after 40 min of feeding. The animals used in this study were five large-type male esophageal- and ruminal-fistulated goats. Roughly crushed alfalfa hay cubes with any large remaining chunks removed were used as feed for this research. The study was conducted under both normal feeding conditions (NFC) and sham feeding conditions (SFC). In the NFC control, the esophageal fistulae were closed by plugs and the animals ate dry forage in the normal manner. In the SFC treatment, before starting the experiment the plugs for closing the esophageal fistula were removed and the cannulae for collecting boluses were fitted into the fistulae. Therefore, the esophageal boluses were removed via an esophageal fistula before they entered the rumen. In the NFC control, eating rates sharply decreased in the first 40 min of feeding and were subsequently maintained at low levels. However, eating rates in the SFC treatment remained high after 40 min of the feeding period had elapsed and the goats ate continuously during the 2 h feeding period. In comparison with the NFC control ($1,794{\pm}203.80\;g$/2 h), cumulative dry forage intake in the SFC treatment ($3,182{\pm}381.69\;g$/2 h) was 77.4% greater (p<0.05) upon conclusion of the 2 h feeding period. In the SFC treatment, cumulative bolus output ($6,804{\pm}469.92\;g$/2 h) was about twofold the cumulative dry forage intake due to cumulative salivary secretion volume ($3,622{\pm}104.13\;g$/2 h) upon conclusion of the 2 h feeding period. The result indicates that large amounts of secreted saliva during dry forage feeding act in conjunction with consumed feed to form the ruminal load responsible for ruminal distension. The increased plasma total protein concentrations were higher in the SFC treatment than in the NFC control. However, plasma and ruminal fluid osmolalities increased in the NFC control during and after feeding but were mostly unchanged in the SFC treatment. In comparison with the NFC control ($3,440{\pm}548.04\;g$/30 min), thirst level in the SFC treatment ($1,360{\pm}467.02\;g$/30 min) was 60.5% significantly less (p<0.05) upon conclusion of the 30 min drinking period. The results of the present study indicate that In the second hour of the 2 h feeding period, dry forage intake is regulated by factors produced when boluses enter the rumen.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1069-1085
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• 2011

In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to clarify whether or not increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding suppress dry forage intake. Eight large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 3 to 6 years, weighing $72.3{\pm}2.74$ kg) were used in two experiments conducted under sham feeding conditions. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 h during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, an intraruminal infusion of artificial parotid saliva (RIAPS) in the control replenished saliva lost via the esophageal fistula and an intraruminal infusion of hypertonic solution (RIHS) in the treatment was carried out in order to reproduce the effects of changing salt content due to feed entering the rumen. In experiment 2, the RIHS control was conducted in the same manner as the RIHS treatment of experiment 1. The treatment group consisted of RIHS-with an intravenous infusion of artificial mixed saliva (VIAMS) treatment that was carried out for 3 h to prevent increases in plasma osmolality during feeding. The results of the RIHS treatment in experiment 1 showed that ruminal fluid osmolality increased and then an increase in plasma osmolality was observed. This resulted in the production of thirst sensations and the reduction of cumulative dry forage intake to 43.3% (p<0.05) of the RIAPS control. The results of the RIHS-VIAMS treatment in experiment 2 indicated that ruminal fluid osmolality was the same as the RIHS control but plasma osmolality significantly decreased, and thirst level was markedly reduced. This caused a significant increase of 31.4% (p<0.05) in cumulative dry forage intake in the RIHS-VIAMS treatment compared to the RIHS control. These results indicate that increases in ruminal fluid osmolality during dry forage feeding indirectly suppresses dry forage intake by causing an increase in plasma osmolality and subsequently inducing thirst sensations. The results of the present study suggest that marked decreases in dry forage intake after 40 min of feeding are caused by increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.1-18
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• 2013

The elements that determine the success of development projects on goats and the prerequisites for ensuring this are discussed in the context of the bewildering diversity of goat genetic resources, production systems, multifunctionality, and opportunities for responding to constraints for productivity enhancement. Key determinants for the success of pro-poor projects are the imperatives of realistic project design, resolution of priorities and positive impacts to increase investments and spur agricultural growth, and appropriate policy. Throughout the developing world, there exist 97% of the total world population of 921 million goats across all agroecological zones (AEZs), including 570 breeds and 64% share of the breeds. They occupy a very important biological and socioeconomic niche in farming systems making significant multifunctional contributions especially to food, nutrition and financial security, stability of farm households, and survival of the poor in the rural areas. Definitions are given of successful and failed projects. The analyses highlighted in successful projects the value of strong participatory efforts with farmers and climate change. Climate change effects on goats are inevitable and are mediated through heat stress, type of AEZ, water availability, quantity and quality of the available feed resources and type of production system. Within the prevailing production systems, improved integrated tree crops - ruminant systems are underestimated and are an important pathway to enhance C sequestration. Key development strategies and opportunities for research and development (R and D) are enormous, and include inter alia defining a policy framework, resolution of priority constraints using systems perspectives and community-based participatory activities, application of yield-enhancing technologies, intensification, scaling up, and impacts. The priority for development concerns the rainfed areas with large concentrations of ruminants in which goats, with a capacity to cope with heat tolerance, can be the entry point for development. Networks and networking are very important for the diffusion of information and can add value to R and D. Well formulated projects with clear priority setting and participatory R and D ensure success and the realisation of food security, improved livelihoods and self-reliance in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.936-940
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• 2008

The PCR-amplified prion protein (PrP) gene was sequenced to determine the frequency of scrapie-associated as well as novel PrP genotypes in 72 healthy goats representing five breeds. A total of six genotypes were detected, resulting from the three reported 143 (H/R), 154 (R/H) and 240 (S/P) and the two novel 39 (S/R) and 185 (I/F) amino acid polymorphisms. Of the four silent mutations 42 (a$\rightarrow$g), 138 (c$\rightarrow$t), 231 (c$\rightarrow$a) and 237 (g$\rightarrow$c) detected in this study, 237 (g$\rightarrow$c) is novel. A genotype (SIP/RFP) harboring three amino acid polymorphisms 39 (S/R), 185 (I/F) and 240 (S/P) was found in few goats. Although both scrapie-associated genotypes with 143 (H/R) and 154 (R/H) polymorphisms and others with 39 (S/R), 185 (I/F) and 240 (S/P) polymorphisms were present in the studied Pakistani goats, their frequency was lower than that of the wild-type genotype SHRIS/SHRIS (34.7%). These results emphasize the need for further sequencing of the PrP gene in a large number of goats representing the five studied breeds, so that overall PrP variability can be assessed in these breeds in research addressing future concerns about scrapie.

• Korean Journal of Veterinary Research
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• v.35 no.1
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• pp.137-142
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• 1995

Anaplasmosis is a tick-borne disease of large and small ruminants, causing losses through mortality, abortion, weight loss and reduced milk production. In one dairy farm, for example, 250 of a total of 800 imported goats were diagnosed with a mysterious type of anemia during the summer and autumn of 1992. The etiologic agent was identified as Anaplasma spp by acridine orange and ultrastructure by electron microscopy. In order to monitor variations in blood biochemical and hematological parameters associated with the disease, blood samples were collected by jugular venipuncture from 50 goats at 3 month intervals between the period of February and October, 1993. The levels of RBCs, HB and HCT decreased from $18.48{\pm}1.96$ to $13.47{\pm}2.48X10^6/mm^3$, $12.25{\pm}1.41$ to $9.54{\pm}1.77g/dl$, and $43.09{\pm}4.75$ to $30.93{\pm}5.78%$, respectively. The values of MCH(Mean corpuscular hemoglobin), MCHC(Mean corpuscular hemoglobin concentration) and PLT(Platelet) were elevated from $6.58{\pm}0.30$ to $7.05{\pm}0.47pg$, $28.40{\pm}1.20$ to $30.82{\pm}1.85g/dl$ and $1688.34{\pm}750$ to $2046.82{\pm}783X10^3/mm^3$, respectively. Percent parasitized erythrocytes(PPE) increased from $0.61{\pm}0.5$ to $2.22{\pm}1.9%$, clinical biochemical parameters aspartate aminotransferase and alanine aminotransferase were $66.64{\pm}23.1K.U$ and $14.90{\pm}6.59K.U$, respectively and persisted at high levels throughout the observation period. The level of albumin(2.46)0.52 g/dl) was decreased corresponding to an elevated globulin and a reduced albumin/globulin ratio in October as compared with the values in February. It is concluded that caprine anaplasmosis may be an important cause of anemia and hepatic malfunction in goats.