Nematode burdens and cellular responses in the abomasal mucosa and blood of Florida Native, Rambouillet and crossbreed lambs

This experiment was carried out to compare the worm burden and cellular responses in the abomasal mucosa and blood of Florida Native and Rambouillet lambs and also in animals produced by crosses of these two breeds (generations F1 and F2). Animals were exposed to infection by gastrointestinal nematodes on three different occasions. The first infection was natural, occurring while they were suckling lambs. After weaning, they were kept indoors for 53 days and then were allowed to graze a contaminated pasture for 50 days for a second natural infection. The third infection was an artificial challenge with 6000 Haemonchus contortus infective larvae. The highest mean fecal egg counts (FEC) values were found in Rambouillet lambs followed in decreasing order by F1, F2 and Florida Native lambs. Throughout the trial, most of the high mean packed cell volumes and plasma protein levels were recorded in the F2 lambs; in contrast, most of the low values were found in the Rambouillet lambs. During the natural infection period, the highest percentages of larvae in the fecal cultures of the lambs were Haemonchus. However, high percentages of Trichostrongylus larvae were found particularly in Florida Native lambs. The mean number of blood eosinophils increased after the artificial challenge, reached a peak 21 days after infection and then declined. The highest and lowest blood eosinophil means were recorded in F2 and Florida Native lambs, respectively. The H. contortus burden was significantly higher in Rambouillet and in F1 lambs than in Florida Native and F2 lambs (p < 0.05), while no significant differences were recorded among eosinophil, mast cell and globule leucocyte counts in the abomasal mucosa (p > 0.05). The highest correlation coefficient recorded at the end of this study was between FEC and worm burden (r = 0.7). These two parameters showed a moderate negative correlation with PCV, plasma protein and mast cell counts in the abomasal mucosa. The results obtained in this study indicate that crossbreeding Florida Native and Rambouillet sheep can be a rapid way to combine and improve the characteristics of these two breeds. The parasitological results were promising. however, more studies will be necessary to verify the impact of crossbreeding in other traits. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Influence of dietary protein supply on resistance to experimental infections with Haemonchus contortus in Ile de France and Santa Ines lambs

The effect of Haemonchus contortus infection in sheep fed with a moderate and high protein content diet was evaluated in two breeds of sheep. Forty-eight Ile de France and Santa Ines lambs were maintained indoors since birth, in worm-free conditions. The lambs were allocated after weaning in four groups of six animals per breed, which were either infected or remain uninfected and given access to either a moderately or highly metabolizable protein diet. The moderately and highly metabolizable protein diets were calculated to supply 75 and 129 g metabolizable protein per kg of dry matter (MP/kg DM), respectively. The infection consisted of a trickle infection with 300 infective larvae, three times a week, for 12 weeks. Significant differences were observed for mast cell, globule leukocyte and eosinophil counts in the abomasal mucosa of the infected groups compared to the control of both breeds (P < 0.05), regardless of the diet supplied. Significantly higher IgA anti-L5 antibody was detected in the infected Santa Ines groups than in the infected Ile de France groups (P < 0.05). Increased metabolizable protein supply resulted in larger body weight gain and higher packed cell volumes for both breeds (P < 0.05). Both breeds showed an increased ability to withstand the pathophysiological effects of H. contortus infection when given access to the highly metabolizable protein diet. However, increased metabolizable protein supply resulted in reduced worm burdens in Santa Ines lambs but not in the Ile de France lambs (P < 0.05). The present results show that the increase in protein content in growing lamb diets may benefit resistance and resilience to gastrointestinal parasites but that these benefits may vary among breeds. (c) 2005 Elsevier B.V. All rights reserved.

Uveitis due to anaplasmosis in a newborn Holstein calf

Relata-se o caso de um bovino com, aproximadamente, seis horas de vida, apresentando histórico de febre, apatia, inapetência e desconforto ocular. No exame oftálmico rotineiro, encontraram-se valores do teste da lágrima de Schirmer aumentados, diminuição da pressão intra-ocular, hemorragia conjuntival, uveíte anterior, edema corneal e injeção ciliar em ambos os olhos. Coletou-se amostra de sangue para realização de esfregaço sangüíneo, hemograma e bioquímica sérica. No esfregaço visibilizaram-se corpúsculos de Anaplasma marginale em hemácias parasitadas. Quanto à bioquímica sérica, não foram observadas alterações. Os mesmos exames foram realizados na mãe do animal tendo como resultado a positividade para A. marginale. Para o controle da uveíte foi utilizada uma única aplicação de 0,5ml de betametasona a 5%, por via subconjuntival, em cada um dos olhos. Para o tratamento da anaplasmose, seguiu-se o protocolo a base de 10mg/kg de oxitetraciclina, por via intramuscular profunda, a cada 12 horas. Diante os achados oftálmicos e a presença de corpúsculos de A. marginale em hemácias parasitadas, contatou-se, ser um caso de uveíte crônica secundaria a doença sistêmica, factível com Anaplasmose.

Annual characteristics of estrous activity in wool and hair ewe lambs under subtropical conditions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Postweaning growth of the non-carcass components of Texel crossbred lambs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ingestive behavior and performance of female lambs grazing on Marandu palisadegrass under different stocking rates

The ingestive behavior and performance of female lambs grazing on Marandu pasture submitted to different stocking rates during the rainy and transition season were evaluated. The experimental area with 4,500 m² was divided into 45 paddocks of 100 m². Twenty-seven Santa Ines female lambs (purebred) with 4 months age and 22 kg of initial body weight were distributed in a completely randomized design, with nine replicates. Lambs were divided into 9 groups with the same initial weight and submitted to three stocking rates: 2, 3 and 4 lambs/paddock, which corresponded to 40, 60 and 80 lambs/ha, respectively. Each group of animals had a module of five paddocks, managed on intermittent grazing system, with 7 days of occupation and 28 d of rest. Increase on time grazing and reduction on time ruminating and resting were observed as stocking rates increased. There was 14% raise in time grazing and 41% decline on time resting by lambs subjected to the highest stocking rate compared with those in the lower stocking rate. The number of animals/ha promoted linear effect on average daily gain, which was higher for animals in the lowest stocking rate of 90 g/d. For gain per area, the best result was obtained with 60 animals/ha featuring an average value of 426 kg/ha.

Mineral requirements for growth of wool and hair lambs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Net and metabolizable protein requirements for body weight gain in hair and wool lambs

Protein is one of the limiting factors in animal production, and the knowledge of protein requirements by livestock is crucial for the success of a commercial animal raising enterprise. Thirty-four castrated lambs, 17 of them F1 Ideal x lie de France wool lambs and the remaining ones were Santa Ines hair lambs, with homogeneous initial BW, were used in the experiment. Five animals from each genotype were slaughtered in the beginning of the experimental period and used as reference. Diets (D) were composed of concentrate mix (C) and Cynodon sp. c.v. Tifton 85 hay (R), combined in three different ratios: D1 =60CAOR; D2=40C:60R and D3=20C:80R. Animals of each group of three lambs, that showed simultaneously an initial BW of 20 +/- 0.14 kg at the beginning of the dietary regimen, were slaughtered when one of them reached 35 kg, what always happened to be the one fed with D1. Net requirements for BW gain in wool lamb, fleece-free, ranged from 101 to 110 g of protein/kg BW, and for hair lamb ranged from 1 10 to 118 g of protein/kg BW. Net protein requirements for wool production ranged from 634 to 642 g/kg of produced wool. Hair lambs presented a 7.8-9.5% higher estimated net protein requirements than wool lambs, according to BW and daily weight gain (DG). Total net protein requirements for Santa Ines and wool lambs, with 30 kg of initial B W and an approximate 200 g mean DG, were 48.5 and 45.4 g/day, respectively. Metabolizable protein requirements for Santa Ines and wool lambs, with 20 kg of initial BW and an approximate 200 g mean DG were 59.4 g and 76.5 -/day, respectively. Net protein requirements for wool production was 64g/100g of produced wool. Thus, under the conditions of this experiment, it is concluded that hair lambs showed a higher concentration of protein in the body, more efficient use of the ingested protein and a consequent additional BW gain when fed isoproteic diets as compared to F1 Ideal x Ile de France wool lambs. (c) 2006 Elsevier B.V All rights reserved.

Net requirements of protein and energy for maintenance of wool and hair lambs in a tropical region

The objective of this work was to evaluate the total endogenous N losses, and protein and energy net requirements for maintenance in growing lambs. Thirty-four castrated lambs, 17 F1 Ideal X Ile de France wool and 17 Santa Inas hair lambs, averaging 20 +/- 0.14 kg BW, were used in the experiment. Five animals from each genotype were slaughtered at the beginning of the experiment and taken as controls. Diets (D) were composed of concentrate mix (C) and Cynodon sp. c.v. Tifton 85 hay (R), combined in three different ratios: D1 = 60C:40R; D2 = 40C:60R and D3 = 20C:80R. Animals of each group of three lambs, that showed BW of 20 kg at the beginning of the dietary regimen, were slaughtered when one of them reached 35 kg, what always happened to be the one fed with D1. Total endogenous N losses estimated for wool lambs were 250 mg N/kg BW0.75. For hair lambs, total endogenous N losses reached 324 mg N/kg BW0.75 . Hair lambs showed higher (P < 0.01) (29.9%) net requirements of protein for maintenance than wool lambs. In contrast, net energy (NE) requirement for maintenance was similar (P > 0.05) for both genotypes (74.27 kcal/kg BW0.75 per day), the average of the antilog of the two intercept values obtained from the estimated regression equations of heat production for zero metabolizable energy (ME) consumption. Further studies should be done to check if this trend is also true for metabolizable energy and protein in animals exhibiting BW gains in tropical region. (C) 2003 Elsevier B.V. B.V. All rights reserved.

SPECIES OF COCCIDIA OCCURRING IN LAMBS IN SAO-PAULO STATE, BRAZIL

The purpose of this experiment was to characterize the species of Eimeria affecting lambs and their infection pattern. Faecal samples were collected from each animal at 14-day intervals, beginning when lambs were 2 weeks old and ending when they were 32 weeks old. The oocysts were counted and identified as E. intricata, E. parva, E. pallida, E. crandallis, E. bakuensis, E. weybridgensis, E. ahsata and E. ovinoidalis. The highest oocyst counts were observed when the lambs were 4-8 weeks old.

Food intake and digestive efficiency in temperate wool and tropic semi-arid hair lambs fed different concentrate: forage ratio diets

This work was conducted to evaluate food intake and digestive efficiency of temperate wool and tropic semi-arid hair lambs, according to different concentrate: forage ratios in diet. Twenty-four lambs, averaging 90 +/- 1.8 days old and a mean body weight of 20 +/- 0.69 kg, 12 of them wool lambs, F, from Ideal x Ile de France crossing, and 12 others pure Santa Ines hair lambs, were distributed into a four replication 3 x 2 factorial arrangement consisting of three diets and two genotypes. Experimental diets consisted of: D1 = 60% concentrate mix (C) and 40% Cynodon sp. cv. Tifton-85 hay (F), D2 = 40% C and 60% F, and D3 = 20% C and 80% F. D1 was formulated for a daily gain of 300g per animal. Increasing forage levels in diets resulted in linear reductions (P < 0.01) in DM, OM, CP, TCH and metabolizable energy (ME) intake, and a linear increase (P < 0.01) in NDF ingestion. Tropic semi-arid hair lambs had higher DM, OM, NDF, CP, and TCH intake than temperate wool lambs. Although there were no genotype effects in OM and GE coefficient of digestibility, hair lambs showed more efficient (P < 0.05) digestibility of DM, CP, NDF and TCH. Increases in forage levels of diets corresponded to a negative linear effect (P < 0.01) in the apparent digestibility of DM, OM, CP, TCH and GE, while apparent digestibility of NDF increased linearly (P < 0.01). Total endogenous nitrogen (fecal plus urinary N) for F(1) Ideal x Ilede France wool and Santa Ines hair lambs were, respectively, 182 and 312 mg/kg(0.75) per day. Thus, Santa Ines tropic semi-arid hair lambs showed to be more responsive than F(1) Ideal x Ile de France temperate wool lambs to low quality fibrous diets. (C) 2004 Elsevier B.V. All rights reserved.

DIABETES AND EXPERIMENTAL PREGNANCY IN RATS - COURSE OF MATERNAL BLOOD-GLUCOSE LEVELS AND ITS REPERCUSSIONS ON THE BLOOD-GLUCOSE LEVELS AND PANCREAS OF NEWBORN PUPS

The objective of the present investigation was to determine the course of maternal blood glucose levels in pregnant rats and its repercussions on the glucose levels and pancreas of their newborn pups. Diabetes was induced by alloxan (42 mg/kg body weight) and streptozotocin (40 mg/kg). Sixty-two pregnant Wistar rats weighing 180 to 250 g were divided into a control group and two groups with moderate (120 to 200 mg/dl glucose) and severe diabetes (greater than 200 mg/dl glucose), respectively. Blood glucose levels were measured in the dams on the 1st, 14th, and 21st days of pregnancy and in the pups at birth. The results were pooled for each litter. The fetal pancreases were removed after cesarian section performed on the 21st day of pregnancy, pooled for each litter and processed for histopathologic examination by light microscopy. Maternal blood glucose levels were significantly increased compared with the first day of pregnancy in both normal and diabetic rats starting on the 14th day of pregnancy. Fetal blood glucose levels correlated with maternal levels. The histopathologic changes characterized by vacuolization and basophilia of the cytoplasm of endocrine pancreas of newborn pups from darns with moderate or severe diabetes suggested pancreatic hyperactivity.