Refinar búsqueda
Resultados 1-9 de 9
Growth and reproductive performance, during exposure to ammonia, of gilts afflicted with pneumonia and atrophic rhinitis.
1993
Diekman M.A. | Scheidt A.B. | Sutton A.L. | Green M.L. | Clapper J.A. | Kelly D.T. | Van Alstine W.G.
From 2 to 4.5 months of age, 80 crossbred gilts were reared in a conventional grower unit where they were naturally exposed to mycoplasmal and bacterial pathogens that cause pneumonia and atrophic rhinitis. At 4.5 months of age, gilts were moved to environmentally regulated rooms (4.9 X 7.3 m) and assigned at random to 1 of 2 treatment groups: low aerial concentration of ammonia (4 to 12 ppm; mean, 7 ppm) or moderate aerial concentration of ammonia (26 to 45 ppm, mean, 35 ppm). Low concentration of ammonia was obtained by flushing of manure pits weekly, whereas moderate concentration of ammonia was maintained by adding anhydrous ammonia to manure pits that were not flushed. Gilts were weighed biweekly. Mean daily gain (MDG) was less (P < 0.01) for gilts exposed to moderate concentration of ammonia than for gilts exposed to low concentration of ammonia after 2 weeks in their respective environments. By 4 and 6 weeks, however, MDG was similar between the 2 treatment groups. After 6 weeks in these environments, 20 gilts from each treatment group were slaughtered, and prevalence and severity of lung lesions and snout grades were determined. At slaughter, body weight was greater (P < 0.01) in gilts exposed to low, rather than moderate, ammonia concentration (94.5 vs 86.8 kg; SEM, 3.3 kg). Percentage of lung tissue containing lesions (18 vs 12) and snout grade (2.8 vs 3.1) were similar between gilts exposed to low or moderate concentration of ammonia. The remaining 20 gilts in each treatment group were maintained in their respective environments, exposed daily to mature boars and bred at first estrus. Age at puberty was similar between gilts exposed to low or moderate concentration of ammonia (208 vs 205 days; SEM, 1.3 days), even though weight at puberty was less (P < 0.03) for gilts exposed to low concentration of ammonia than for gilts exposed to moderate concentration of ammonia (109.7 vs 118.2 kg; SEM, 4.5 kg).
Mostrar más [+] Menos [-]Effect of subchronic oral exposure to zearalenone on the reproductive system of rabbit bucks
2018
Tsouloufi, Theodora K. | Tsakmakidis, loannis A. | Tsousis, Georgios | Papaioannou, Nikolaos | Tzika, Eleni | Kritsepi-Konstantinou, Maria
OBJECTIVE To determine the effect of subchronic oral exposure to zearalenone (ZEA) at a daily dose of 50 μg of ZEA/kg of body weight (an environmentally relevant concentration) on the reproductive system of rabbit bucks. ANIMALS 8 healthy sexually mature New Zealand White rabbits. PROCEDURES During the experimental period (March to June), each rabbit underwent a 7-week control protocol and then a 7-week treatment protocol. Water (0.5 mL) or ZEA solution (50 μg/kg [0.5 mL]) was administered orally once daily during the control and treatment period, respectively; ejaculates were collected weekly. Studied end points included semen quality variables (spermatozoa kinetics, morphology, viability, and DNA fragmentation), serum testosterone concentration, and results of histologic examination of the testes and epididymides following euthanasia at the end of the experimental period. RESULTS Treatment with ZEA solution resulted in significant increases in spermatozoa beat-cross frequency, in the percentages of spermatozoa with head and midpiece abnormalities, and in the percentages of DNA-fragmented spermatozoa, compared with effects of the control treatment. Serum testosterone concentration, other spermatozoa velocity variables, and percentages of progressive and total motility, rapidly or slowly moving spermatozoa, and live spermatozoa did not differ significantly between the 2 periods. Histologic examination revealed no patterns of abnormal findings in the testes and epididymides. CONCLUSIONS AND CLINICAL RELEVANCE Oral treatment with ZEA solution at an environmentally relevant concentration caused minor interference with rabbit bucks' sperm quality. Although mostly considered mild, the sperm quality changes warrant further investigation in terms of fertilizing capacity impairment.
Mostrar más [+] Menos [-]Ultrasonographic assessment of the thyroid gland and adjacent anatomic structures in Indo-Pacific bottlenose dolphins (Tursiops aduncus)
2012
Objective: To evaluate the use of ultrasonography for thyroid gland assessment in healthy Indo-Pacific bottlenose dolphins (Tursiops aduncus), describe the ultrasonographic appearance of the thyroid gland and adjacent anatomic structures, and identify potential associations between variations in thyroid gland morphology and demographic features in this species. Animals: 18 captive Indo-Pacific bottlenose dolphins. Procedures: 1,404 ultrasonographic examinations of the thyroid gland and adjacent anatomic structures (eg, cervical lymph nodes, musculature, and vasculature) were performed during the > 3-year study period. Shape, echogenicity, and homogeneity of thyroid glands were assessed, and glands were categorized into morphological configurations on the basis of results of 2-D and 3-D ultrasonographic evaluation. Associations between demographic factors and thyroid gland morphology were assessed. Results: Thyroid lobes appeared elliptical or fusiform in the transverse scan plane and round to oval in longitudinal scan planes; morphologically, glands comprised 2 lobes joined by an isthmus or a roughly diamond-shaped structure located on the ventral surface of the trachea. Major blood vessels and cervical lymph nodes were identified. Thyroid parenchyma was typically uniform and homogeneous, with echogenic reticulations and well-defined borders. Thyroid glands were hypoechoic or isoechoic relative to the sternocephalicus muscle; echogenicity was greater in adolescents than in adults. Thyroid gland volume differed between sexes, between sexually mature and immature dolphins, and among age groups and was positively correlated with body length and weight. Conclusions and Clinical Relevance: Ultrasonography provided a reliable and repeatable method for evaluation of thyroid glands and adjacent anatomic structures in live dolphins.
Mostrar más [+] Menos [-]Prevalence of True Anoestrus and Delayed Puberty in Cattle.
2009
Bhattacharyya, H. K. | Makhdoomi, D. M. | Hafiz, A.
An overall prevalence of 20.07% true anoestrus and delayed puberty in cattle was recorded out of 2202 gynaecological cases presented to the clinical complex and different clinical camps held at different locations of Kashmir valley over a period of three years (2005_2008). The highest prevalence of true anoestrus in cows was recorded in the 1st parity when they attained approximately 3 years of age and during autumn season.
Mostrar más [+] Menos [-]Ameliorative effects of exogenous gonadotropins on reproductive profiles of replacement gilts with delayed puberty in a farm in Thailand
2017
Am-In, N. (Chulalongkorn University, Bangkok (Thailand). Faculty of Veterinary Science, Department of Obstetrics, Gynaecology and Reproduction) | Roongsitthichai, A.
Serum oestradiol-17â and progesterone concentration at puberty in piglets weaned at different days.
2010
Gogoi, Ruprekha | Sarmah, B. K. | Sarmah, B. C. | Deka, B. C. | Kalita, D.
Eight female piglets from each of three farrowed crossbred (75% Hampshire x 25% Local) gilts grouped as A, B and C were weaned at 28, 42 and 56 days respectively. Piglets of each weaned groups were divided into two sub-groups _ 'a' and 'b' consisting of 4 piglets in each. Piglets of sub-groups _ 'a' were supplemented with strategic mineral mixture while the piglets of sub-group 'b' were offered commercial mineral mixture. There was significant (P0.01) rise of serum oestradiol-17â at the pubertal oestrus compared to the levels before puberty in gilts. Oestradiol concentration did not differ significantly among piglets weaned at different days of age and between piglets supplemented with strategic and commercial mineral mixture. Serum progesterone was lowest during oestrus and highest on day 10 of the oestrus cycle in all the groups. Progesterone concentration in the piglets weaned at different days of age did not differ significantly. However, the level was found significantly (P 0.05) high in piglets supplemented with strategic mixture over the piglets supplemented with commercial mineral mixture.
Mostrar más [+] Menos [-]The use of plasma progesterone profiles to determine the puberty in Korean native heifers
1993
Kang, B.K. | Choi, H.S. | Shon, C.H. (Chonnam National University, Kwangju (Korea Republic). College of Veterinary Medicine) | Suh, K.H. (National Animal Breeding Institute, Sunghwan (Korea Republic))
The age at puberty and breeding season in Korean native goats
1992
Kang, B.K. | Choi, H.S. | Park, Y.J. | Park, B.J. | Son, C.H. (Chonnam Nat'l Univ., Kwangju (Korea Republic). Coll. of Veterinary Medicine)
On the gonadal maturation and growth curves of females of saguiru prata (Steindachnerina insculpta Fernandez-Yepez, 1948), in Ibitinga reservoir, Sao Paulo state, Brazil
1991
Santos, R.A. dos | Camara, J.J.C. da | Campos, E.C. | Mandelli Junior, J.