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111.
Reena Kamal Triveni Dutt Manjunath Patel Amitava Dey Panch Kishore Bharti Poolangulam Chinnakkan Chandran 《Tropical animal health and production》2018,50(4):701-706
In tropical countries, at high temperatures, several physiological rearrangements occur in cows as they attempt to facilitate heat dissipation and/or reduce metabolic heat production. Following exposure to heat, cattle appear to acclimatize within 2–7 weeks. The failure of homeostasis at high temperatures may lead to reduced productivity or even death. The situation is even worse when humidity adds to high temperature. Livestock with elevated body temperature exhibit lower DMI and growth with less efficiency, reducing profitability for dairy farms in hot and humid climates. Shading of feed and water also offers production advantages. Although several elaborate methods for reducing heat stress in cows have been reported, simple shade materials appear to be the most cost-effective methods that are currently applicable to tropical developing countries. Different materials are being used to provide shade during warm weather. The shade material determines the microclimate—it should be light, strong, durable, weatherproof, good looking and a bad conductor of heat, and free from tendency to condense moisture inside. This review discusses various shade materials and their advantages and disadvantages in different situations. 相似文献
112.
Eric Lim Teik Chung Michael Predith Frisco Nobilly Anjas Asmara Samsudin Faez Firdaus Abdullah Jesse Teck Chwen Loh 《Tropical animal health and production》2018,50(8):1727-1732
Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant. 相似文献
113.
Shafarin MS Zamri-Saad M Khairani BS Saharee AA 《Tropical animal health and production》2008,40(5):335-340
This report describes the proliferation and transmission patterns of Pasteurella multocida B:2 among stressful goats, created through dexamethasone injections. Thirty seven clinically healthy adult goats were divided
into three groups consisted of 15 goats in group A, 11 goats in group B and the remaining 11 in group C. At the start of the
study, all goats of group A were exposed intranasally to 1.97 × 1010 CFU/ml of live P. multocida B:2. Dexamethasone was immediately administered intramuscularly for 3 consecutive days at a dosage rate of 1 mg/kg. The exposed
goats were observed for signs of HS for a period of 1 month. At the end of the 1-month period, 11 goats from group B were
introduced into and commingled with the surviving goats of group A before all goats from both groups were immediately injected
intramuscularly with dexamethasone for 3 consecutive days. The treatment with dexamethasone was then carried out at monthly
interval throughout the 3-month study period. Goats of group C were kept separately as negative control. Three surviving goats
from each group were killed at 2-week interval for a complete post-mortem examination. Two (13%) goats of group A were killed
within 24 hours after intranasal exposure to P. multocida B:2 while another two (13%) goats from the same group were killed on day 40, approximately 10 days after the second dexamethasone
injection. All four goats showed signs and lesions typical of haemorrhagic septicaemia. Bacteraemia was detected in 3 goats
of group A that were having rectal temperature higher than 41°C. The P. multocida B:2 isolation pattern was closely associated with dexamethasone injections when significantly (p < 0.05) higher rate of isolations
from both groups were observed after each dexamethasone injection. Transmission of P. multocida B:2 from goats of group A to group B was successful when P. multocida B:2 was isolated from goats of group B for a period of 28 days. There was a strong correlation between dexamethasone injections,
rate of bacterial isolation and serum cortisol level. The IgG level showed an increasing trend 2 weeks after exposure to P. multocida B:2 and remained high throughout the study period. 相似文献
114.
The aims of this study were to determine vertebral heart size (VHS) in stray cats and to compare different radiographic views. This study was performed on 50 adult stray cats. All cats were short-haired and non-obese and were considered to be healthy based on physical examination and electrocardiography. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken. The long and short axes of the heart were measured in millimetres. The thoracic vertebral length spanned by each dimension was measured caudally from the fourth thoracic vertebra. Mean+/-SD and the correlation coefficient between the measurements were calculated with standard statistical software. The sum of the long and short axes of the heart expressed as VHS was 7.3+/-0.49 vertebrae in right lateral, 7.3+/-0.55 vertebrae in left lateral, 7.5+/-0.68 vertebrae in dorsoventral and 7.5+/-0.53 vertebrae in ventrodorsal. The differences between right and left lateral as well as dorsoventral and ventrodorsal views were not significant (P>0.05). Absolute measurements and vertebral heart scale values were slightly smaller than those reported in the literature for mixed population of cats. It is, therefore, important to take the breed in to account. 相似文献
115.
After very hot summer, 22 sheep from 5 different flocks consisting of approximately 150-200 animals each were diagnosed with facial eczema in September 2005, in southwest Turkey. Photophobia, corneal opacity, severe ulcers of the facial skin, especially localized around the eyes and mouth, and 3% mortality were the most prominent clinical symptoms. GGT levels of the animals were very high and varying between 261- 328 U/l. While the activities of ALT and total bilirubin were elevated and AST was normal in affected sheep. Total bilirubin level was higher than normal. Seven of the 22 sheep were euthanatized and necropsy was performed on all of these animals. Severe icterus, hepatomegaly, enlarged gallbladder, congestion of mesenteric vessels were the common necropsy findings. Histopathological changes of the liver included necrosis of the hepatocytes, cholangiohepatitis characterized by mononuclear inflammatory cell infiltrate in the portal area and mild to severe fibrosis around bile ducts. A diagnosis of sporidesmin toxicosis was made based on the histopathology of the livers, the elevation in liver enzymes, and the development of cutaneous lesions consistent with photosensitization and high spore counts in the ruminal contents. Surviving sheep were treated with procaine penicillin + dihidrostreptomycin sulfate, multivitamin complexes and flunixin meglumine. Additionally, zinc sulphate was also given at a dose of 6 gr per 100 lt drinking water for 28 days. All treated sheep recovered. Pasture spore counts were between 96,300- 267,500 spores/g grass. 相似文献
116.
Randhawa SS Dua K Randhawa CS Randhawa SS Munshi SK 《Veterinary research communications》2008,32(8):599-608
The effect of biotin supplementation on various foot lesions and hoof ceramide composition of toe (wall) and sole portions
of hooves was studied in crossbred dairy cattle. Biotin supplementation was done for five months in 14 cattle at a farm and
the other 14 animals kept as control. A significant decline was observed in heel erosions and sole avulsions along with total
disappearance of white line fissures and double soles in the biotin supplemented cattle resulting in decrease in the overall
disease score. Thin layer chromatographs of the hoof lipids revealed 11 types of ceramides in sole lipids and 6 types of ceramides
in toe (wall) lipids. The ceramides were typed and identified according to their Rf values. A qualitative increase in the
density of thin layer chromatographs of sole lipids was observed in biotin supplemented cattle whereas a non-significant difference
in density of thin layer chromatographs of toe lipids was observed after supplementation of biotin. 相似文献
117.
Othman Alqaisi O. Assah Ndambi Mohammad Mohi Uddin Torsten Hemme 《Tropical animal health and production》2010,42(6):1063-1071
The development of the dairy industry plays an important role in the economy of Middle Eastern countries. Judged by its growth
rate, the dairy industry is viewed as one of the most progressive food industries in the Middle East. During the early 1970s,
countries established executive programs to promote dairy farming; the major objective was to attain self-sufficiency in milk
production. A massive investment was set up for importing top class cattle, complying with top industry operating standards,
and a simultaneous introduction of the latest technology in processing, packaging, and distributing. Milk production has grown
tremendously at rates of 6.6% and 4.9% in Syria and Saudi Arabia, respectively, between 2002 and 2007, which resulted in these
nations being almost self-sufficient. Regarding Jordan, milk production has not yet met this target. An excessive growth in
the dairy industry is quite noticeable in this region with an expanding capacity for exports. The aim of this study is to
show the most recent trends and future prospects of the dairy industries in Syria, Saudi Arabia, and Jordan. It also attempts
to investigate the drivers for the development of milk production, consumption, and trade in the region. 相似文献
118.
Krishna Mohan Vijay Kumar Mihir Sarkar B. S. Prakash 《Tropical animal health and production》2010,42(1):21-26
The objective of this study were (1) to establish the duration of behavioral estrus signs and timing of ovulation in Murrah
buffaloes (n = 10) and (2) to determine relationship between behavioral estrus signs with change in plasma estrogen concentrations.
Estrus and its behavioral signs were detected at hourly intervals by visual observations, per recta examination of genitalia
and bull parading four times in a day for 30 minutes each. Among the behavioral signs of estrus, swollen vulva (80%) was the
best indicator of estrus followed by excitement (70%). Among the duration of behavioral estrus signs the first and longest
duration of estrus signs was swollen vulva which was seen upto 19.8 ± 0.8 h after onset of estrus. The mean total duration
of estrus symptoms from appearance to disappearance of all the behavioral estrus symptoms was 23.5 ± 1.7 h. All the behavioral
estrus symptoms were observed during the period of estrogen surge. Endocrine profile during the periestrus period showed that
the mean peak concentrations of total estrogen 23.9 ± 3.9 pg/ml occurred at 8.8 ± 1.7 h after onset of estrus. The average
number of estrus symptoms observed per animal during onset of spontaneous estrus was 5.7. Ovulation occurred after 37.4 ± 1.7 h
after onset of estrus and 13.4 ± 1.0 h after end of total estrogen surge respectively. In conclusion, our results suggest
that all signs of behavioral estrus occurred during the preovulatory rise in estrogens. The first sign of estrus to be observed
was a swollen vulva and this symptom persisted the longest. 相似文献
119.
Prettimore Mafirakureva Bamusi Saidi Joshua Mbanga 《Tropical animal health and production》2017,49(1):47-54
Between January, 2013 and December, 2014, there was a lumpy skin disease (LSD) outbreak that affected cattle in different localities of Zimbabwe. The outbreak resulted in severe economic losses to the livestock industry. A retrospective study was conducted by examining stored veterinary records of the LSD outbreak at the Central Veterinary Laboratory (CVL) in Harare, Zimbabwe. Over the 2-year period, a total of 10,038 cases and 880 deaths (8.77 %) were recorded. LSD was reported from all regions of the country, with the highest incidence occurring in Mashonaland West (30.95 %) and Midlands province (14.59 %). The frequency of reported outbreaks was highest in March and April, with the lowest reported cases occurring in November. A total of 25 representative specimens (skin biopsies) were collected from nodular skin lesions of infected cattle, and after viral DNA isolation, the P32 gene was successfully amplified, by using PCR, in 88 % (22/25) of all assayed specimens. Out of the 22 samples that showed amplification, 16 (73 %) were selected for DNA sequencing, and from these, 13 sequences were submitted to GenBank and assigned accession numbers: KX033494, KX033495, KX033496, KX033497, KXO33498, KX033499, KX033500, KX033501, KX033502, KX033503, KX033504, KX033505 and KX033506. Phylogenetic analyses of the 13 sequences was done by using MEGA 7 and showed that the viruses formed two major clusters implying that at least two strains of LSDV are in circulation in Zimbabwe. This study provides the first report on the incidence and molecular characterisation of LSDV in Zimbabwe. 相似文献
120.
Cesar García-Hernández Javier Arece-García Rolando Rojo-Rubio German David Mendoza-Martínez Benito Albarrán-Portillo José Fernando Vázquez-Armijo Leonel Avendaño-Reyes Agustín Olmedo-Juárez Carine Marie-Magdeleine Yoel López-Leyva 《Tropical animal health and production》2017,49(1):55-61
Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5 mg of FCT kg?1 of body weight (BW); sterile water (control); and ivermectine (0.22 mg kg?1 of BW) as chemical group. The data were processed through repeated measurement analysis. Even though the three FCT doses decreased (P?<?0.05) the FEC, the highest reduction was obtained with 37.5 mg kg?1 of BW. No differences were observed in PCV and OMC. Higher ADG (P?<?0.05) was observed with 37.5 mg kg?1 of BW of FCT. The count of adult nematodes (females and males) in the higher dose of FCT was similar to chemical treatment. Dose of 37.5 mg kg?1 of BW decreased the parasite infection and improved the lamb performance. Therefore, this dose could be used as a nutraceutic product in sheep production. 相似文献