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21.
The effect of a single intramammary infusion of a biological response modifier in cows at drying off
Bibiana Elisabet Dallard H. H. Ortega I. A. Iguzquiza N. R. Salvetti O. A. Quaino L. F. Calvinho 《Veterinary research communications》2010,34(6):519-532
Biological response modifiers (BRM) are compounds that interact with the immune system to regulate specific aspects of host
response. The objective of this study was to describe clinical and morphological changes during involution of bovine mammary
gland following a single-dose infusion of a BRM containing lipopolysaccharide and cellular fractions of Escherichia coli incorporated into liposomes. A massive leukocyte response and increased subepithelial stroma infiltration of mononuclear
cells, eosinophils and mast cells was observed in BRM-treated quarters compared with untreated controls; however, morphologic
parameters assessed at 11 days post infusion were indicative of only slightly accelerated involution compared with untreated
controls. In addition, BRM infusion at the end of lactation did not interfere with mammary epithelial cell proliferation and
caused only mild systemic effects. 相似文献
22.
Schlanser JR Patterson JS Kiupel M Hencken C Sikarskie JG Harrison TM 《Journal of zoo and wildlife medicine》2012,43(2):407-411
A 21-yr-old male North American river otter (Lontra canadensis) with a chronic history of degenerative osteoarthritis was evaluated for acute posterior paralysis. Because no definitive cause was identified and a poor prognosis was expected, the otter was euthanatized. A malignant neoplasm of adrenal gland origin with disseminated metastases to the central nervous system, lymph nodes, diaphragm, pancreas, spleen, and liver was diagnosed on postmortem examination. No clinical signs of disseminated neoplasia had been noted throughout the otter's history. The adrenal neoplasm was composed of nests of epithelial cells surrounded by a fine fibrovascular stroma. Neoplastic cells were immunohistochemically positive for chromogranin A, PGP9.5, metencephalin, and endorphin and negative for melan A and inhibin, confirming a diagnosis of a malignant pheochromocytoma. On the basis of the necropsy finding, metastasis of the pheochromocytoma might have contributed to the observed clinical signs. 相似文献
23.
Monde Mapekula Michael Chimonyo Cletos Mapiye Kennedy Dzama 《Tropical animal health and production》2010,42(7):1413-1419
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities.
The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern
Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected
households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l
per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early
lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee
or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had
the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities
of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems. 相似文献
24.
Kagira JM Kanyari PN Githigia SM Maingi N Ng'ang'a JC Gachohi JM 《Tropical animal health and production》2012,44(3):657-664
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This
study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from
135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique.
The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also
administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode
eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free
range pigs in Busia District, which can be used when implementing integrated control measures. 相似文献
25.
Jemberu Dessie Solomon Melaku Firew Tegegne Kurt J. Peters 《Tropical animal health and production》2010,42(5):841-848
The experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at Wogda (Ethiopia) to determine
the effect of supplementation of graded levels of concentrate mix (CM) on feed intake, digestibility, and body weight (BW)
change in hay-based feeding of Simada sheep. Twenty-yearling Simada sheep with a mean initial BW of 17.9 ± 0.81 kg (mean ±
SD) were used in randomized complete block design arranged into five blocks of four animals. The four dietary treatments that
consisted of hay alone (T1), hay +150 g dry matter (DM; T2, low), hay +250 g DM (T3, medium), and hay +350 g DM (T4, high)
CM were randomly assigned to each sheep within a block. The CM consisted of wheat bran (WB), noug seed (Guizotia abyssinica) meal and safflower (Carthamus tinctorius) seed meal at the ratio of (2:1:1), respectively. Supplementation with T2 and T3 increased (P < 0.001) total DM and organic matter intake than the control treatment. Overall, supplementation improved (P < 0.001) crude protein intake, digestibility, feed conversion efficiency, BW gain, and profitability compared to the control,
whereas sheep on the high than the low and medium level of supplementation performed better in these parameters among the
supplemented treatments. From the results of this study, T4 is recommended as the best level of supplementation since it resulted
in better nutrient utilization, animal performance, and profitability. 相似文献
26.
Sawalha MN Kridli RT Jawasreh KI Meza-Herrera CA 《Tropical animal health and production》2011,43(7):1345-1350
This experiment was conducted to evaluate the effect of administering hormonal treatments (melatonin and progestagen/equine chronic gonadotropin (eCG)) on advancing puberty in Awassi ewe lambs. Fifty-one 6-month-old ewe lambs of similar body weights (around 28 kg) were randomly assigned into four treatment groups; control (CON; n?=?14), melatonin (MEL; n?=?13), melatonin plus progestagen–eCG (MELPP; n?=?11), and progestagen–eCG (PP; n?=?13). Ewe lambs in the PP and MELPP groups were fitted with intravaginal progestagen sponges containing 60 mg medroxyprogesterone acetate for 14 days; 400 IU eCG were administered to each of these ewe lambs on the day of sponge removal. Ewe lambs in the MEL and MELPP groups received subcutaneous melatonin implants (Regulin®, 18 mg melatonin) 36 days before sponge insertion. Hormonal treatment had no effect on ewe lamb body weight change. Estrous behavior was greater (p?0.001) in the PP and MELPP groups than in the CON and MEL ewe lambs. The duration from ram introduction to onset of estrus was shorter (p?0.05) in the CON, PP, and MELPP than in the MEL ewe lambs. The number of ewe lambs showing luteal activity was greater (p?0.001) in the MELPP and PP than in the CON and MEL groups. Lambing rate from mating during the first cycle following ram introduction differed significantly (p?0.01) among treatments being greater in the MELPP and PP than in the CON and MEL groups. Based on these results, it can be concluded that progestagen–eCG appears to be more effective than melatonin in inducing reproductive activity. However, the majority of ewe lambs in the current study either failed to cycle or stopped cycling following the induced estrus. Such failure in advancing puberty may be related to body weight of ewe lambs at the time of mating. 相似文献
27.
S. Kennou Sebei R. Bergaoui M. Ben Hamouda R. G. Cooper 《Tropical animal health and production》2009,41(7):1427-1438
The aim of the current investigation was to determine wild ostrich reproductive behaviour in Orbata Nature Reserve by observing
16 hens and 28 cocks over a seven-year period. Intense laying commenced in January, one month after the cessation of the rainy
season, and 92% of the eggs were produced during the dry season (January to May, peaking in March). Over the seven years,
1,322 eggs were laid in 69 nests, which corresponded to an annual average production of 19.2 ± 9.1 eggs/nest and 11.8 eggs/hen.
24 nests (34.78%) were non-brooded, 17 nests (24.64%) were deserted in the course of incubation, and 28 nests (40.58%) possessed
hatched eggs. All the non-incubated nests had egg losses equivalent to 46.6 ± 12.6%. Hatchability success of incubated eggs
was 41.9 ± 12.0%. Ostriches tended to dig their nests adjacent to the reserve enclosure which had direct access by road and
track, the latter subjecting them to human disturbance and predation. The systematic obstruction of these nests stimulated
ostriches to build additional nests within the reserve perimeter. The authors discussed the results recorded in an ostrich
flock in relation to the environmental factors (climatic factors, food disponibility and predation) and suggested possibilities
for improved wildlife management. 相似文献
28.
Effects of tea saponins on rumen microbiota,rumen fermentation,methane production and growth performance—a review 总被引:1,自引:0,他引:1
Reducing methane emission from ruminant animals has implications not only for global environmental protection but also for
efficient animal production. Tea saponins (TS) extracted from seeds, leaves or roots of tea plant are pentacyclic triterpenes.
They have a lasting antiprotozoal effect, but little effect on the methanogen population in sheep. There was no significant
correlation between the protozoa counts and methanogens. The TS decreased methanogen activity. It seems that TS influenced
the activity of the methanogens indirectly via the depressed ciliate protozoal population. The TS addition decreased fungal
population in the medium containing rumen liquor in in vitro fermentation, but no such effect was observed in the rumen liquor
of sheep fed TS. Tea saponins had a minor effect on the pattern of rumen fermentation and hence on nutrient digestion. When
added at 3 g/day in diets, TS could improve daily weight gain and feed efficiency in goats. No positive associative effect
existed between TS and disodium fumarate or soybean oil on methane suppression. Inclusion of TS in diets may be an effective
way for improving feed efficiency in ruminants. 相似文献
29.
30.
Avian mycobacteriosis is an important disease in companion, captive, exotic, and wild birds worldwide. Mycobacterium avium is the most widely distributed and pathogenic organism causing tuberculous lesions in birds. Multiple factors including age, stress, immune status, and preexisting disease determine the pathogenicity of M. avium, and the disease can manifest itself in a variety of forms. Mycobacteriosis can cause severe losses in zoo aviaries, including the loss of rare and endangered bird species. We report a case of systemic avian mycobacteriosis in an adult, free-living male American bald eagle (Haliaeetus leucocephalus) that presented to the Diagnostic Center for Population and Animal Health in November 2003. 相似文献