Growing hairs in shorn cattle / Crescimento do pelo em bovinos tosquiados

The shearing operation can provide double benefits to the cattle: they can become more heat tolerant and the tick infestation decreases. The cattle tick Rhipicephalus (Boophilus) microplus causes great losses to dairy cattle, especially to the Holstein cattle because they are very susceptible to this tick. Its control is becoming each day more difficult, owing to the increasing resistance to acaricides they are acquiring. The objective of this work was to study the growing of haircoat following shearing. We made our experiment with 17 animals, 7 females and 10 males. They were shaved on the anterior third (head, neck, dewlap, scapula and arm) of one side, at random. The work was performed in two steps: they were shorn for the first time on August 2nd 2012, with a size 10 blade in a clipper Oster model GoldenA5, which left the fur coat 2 mm long. Then we evaluated the hair length growing by collecting fortnightly three sample of hairs in the middle of the scapula, with  electric pliers, modified for this purpose, in both sides of the animals, sheared and non-sheared, until 30 days after this shearing. The three hair samples were put inside a little plastic bag per animal. Meanwhile, as we thought that the animals shearing had to be done closer to the skin, we decided to shear them again (in the same side shorn before), on October 2nd 2012. We changed our procedure using the same

O artigo não apresenta resumo em português.

Filiform papilla of holsteins tongue and its relation with the Rhipicephalus microplus tick resistance / Papila filiforme da língua de novilhas holandesas e sua relação com a resistência ao carrapato Rhipicephalus microplus

Several studies describe anatomical, morphological and histological analysis of domestic and wild animals tongue. The tongue is an extendable muscular organ that performs gripping, chewing, and swallowing food actions and executes tasting and mechanical body self-cleaning functions (grooming). The distribution of these tongue characteristics may vary, according to different species, but studies made with different animals classes reveal the filiform papilla acting in mechanical body cleaning function. In order to evaluate these mechanical functions, especially the self-cleaning one, we proposed to investigate filiform papillae length or its base dimensions would be related to the heifers resistance to Rhipicephalus microplus tick. Biopsies were performed in eight (8) Holstein heifers tongues, with a 6 mm diameter punch, in the anterior third of tongues, at the distance of 3 cm from its tip. The animals were anesthetized with xylazine hydrochloride 2%, a sedative, analgesic and muscle relaxant and received local anesthetic, hydrochloride 2.0 g lidocaine. After tissue removal, the local lesions received an ointment of triamcinolone acetonide, 1.0 mg g-1. The Holstein heifers were one year and half old and naturally infested with ticks in a paddock situated at Instituto de Zootecnia. We monitored their natural infestation by counting females ticks, greater than 4.5 mm, presents

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. I. Hair length and coat thickness / Resistência ao carrapato e tolerância ao calor em bovinos. I. Comprimento e espessura do pelame

To be heat adapted and Rhipicephalus (Boophilus) microplus tick resistant are important characteristics for cattle in the Brazilian sustainable livestock, because this ectoparasite causes serious harm to the health of susceptible animals and, in the tropics, not heat adapted cattle have poor performance. Besides, the control of this tick is increasingly difficult due to drug resistance. Relationship between tick infestation and heat tolerance traits, as the hair length and coat thickness, are important because animals with long hair are easily identifiable, helping in the disposal of the least adapted cattle. In order to infer the relationship between tick infestation and fur characteristics, 6 Nellore and 4 Black and White Holstein steers, with about seven months old, underwent an artificial infestation (with 10,000 larvae on the Holstein, and 20,000 larvae on the Nellore) in 16/April/2011. In days 20, 23 and 24 post-infestation, the bigger 10 females ticks found throughout the body were weighed and their egg mass weighed 14 days later. Hair length, HL (collected with pliers specially adapted for this purpose, and measured the 10 longest hair) and the coat thickness, CT (measured with a metal ruler inserted perpendicular to the skin) were evaluated in the middle of the shoulder on 11/April (5 days before artificial tick infestation) and on 12/May (26 days after artificial tick

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. II. Rectal temperature and respiratory frequency / Resistência ao carrapato e tolerância ao calor em bovinos. II. temperatura retal e frequencia respiratória

The heat and Rhipicephalus microplus tick infestation are limiting factors to the livestock production in the tropics. Therefore, in a tropical sustainable livestock, cattle should be tick resistant and heat tolerant. The relationship between the Rhipicephalus (Boophilus) microplus tick infestation and heat characteristics like rectal temperature and respiratory frequency was studied in 6 Nellore and 4 Holstein, seven-month-old steers. They were submitted to an artificial infestation (a.i.) with 10,000 larvae (Holstein) and 20,000 larvae (Nellore) of Rhipicephalus (Boophilus) microplus tick in 16/Apr/2011. Females ticks bigger than 4.0 mm were counted in the left side from day 19 to 27 after the artificial infestation. The infestation rate was calculated by summing and multiplying by two the number of ticks counted, assuming that females are half of infesting larvae (5,000 for Holstein and 10,000 for Nellore). In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH), weighing the egg mass of each female fourteen days after. The rectal temperature (RT, measured by a digital thermometer in the animals rectum) and respiratory frequency (RF, respiratory movements per minute) were measured on days 14/Apr (2 days before the a.i.) and on day 05/May (19 days after the a.i.). The RT and RF were m

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. III. Sweating rate / Resistência ao carrapato E tolerância ao calor em bovinos III. taxa de sudação

Cattle in a sustainable tropical livestock should be heat tolerant and resistant to ticks. The relationship between Rhipicephalus (Boophilus) microplus infestation and sweating rate, an important heat tolerance characteristic, was studied in six Nellore and four Holstein steers of seven-month-old. They were artificial infested (a.i.) with 10,000 (Holstein) and 20,000 (Nellore) larvae in 16/Apr/2011. In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH), weighing the egg mass of each female tick fourteen days after. The sweating rate (SRskin, measured by Scheleger and Turner, 1963, method, in a shaved area of shoulder skin) was evaluated in 14/Apr (2 days before the a.i.) and in 05/May (19 days after a.i.). In 14/Apr the Scheleger and Turner, 1963, method was done on the coat not shaved (SRcoat). The sweating rate was measured in the afternoon (from 2 P.M.), after 30 minutes of direct sunlight, on April. On May, the animals remained 60 minutes in direct sunlight because this day was colder. The experimental design was a non-probability sample restricted to the 10 available animals. Data from the steers sweating rate were analyzed using the General linear models of the SPSS® statistical package (version 12.0) using SRskin as dependent variable and breed and sampling date as independent

O artigo não apresenta resumo em português.

Growing hairs in shorn cattle / Crescimento do pelo em bovinos tosquiados

The shearing operation can provide double benefits to the cattle: they can become more heat tolerant and the tick infestation decreases. The cattle tick Rhipicephalus (Boophilus) microplus causes great losses to dairy cattle, especially to the Holstein cattle because they are very susceptible to this tick. Its control is becoming each day more difficult, owing to the increasing resistance to acaricides they are acquiring. The objective of this work was to study the growing of haircoat following shearing. We made our experiment with 17 animals, 7 females and 10 males. They were shaved on the anterior third (head, neck, dewlap, scapula and arm) of one side, at random. The work was performed in two steps: they were shorn for the first time on August 2nd 2012, with a size 10 blade in a clipper Oster model GoldenA5, which left the fur coat 2 mm long. Then we evaluated the hair length growing by collecting fortnightly three sample of hairs in the middle of the scapula, with  electric pliers, modified for this purpose, in both sides of the animals, sheared and non-sheared, until 30 days after this shearing. The three hair samples were put inside a little plastic bag per animal. Meanwhile, as we thought that the animals shearing had to be done closer to the skin, we decided to shear them again (in the same side shorn before), on October 2nd 2012. We changed our procedure using the same

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. III. Sweating rate / Resistência ao carrapato E tolerância ao calor em bovinos III. taxa de sudação

Cattle in a sustainable tropical livestock should be heat tolerant and resistant to ticks. The relationship between Rhipicephalus (Boophilus) microplus infestation and sweating rate, an important heat tolerance characteristic, was studied in six Nellore and four Holstein steers of seven-month-old. They were artificial infested (a.i.) with 10,000 (Holstein) and 20,000 (Nellore) larvae in 16/Apr/2011. In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH), weighing the egg mass of each female tick fourteen days after. The sweating rate (SRskin, measured by Scheleger and Turner, 1963, method, in a shaved area of shoulder skin) was evaluated in 14/Apr (2 days before the a.i.) and in 05/May (19 days after a.i.). In 14/Apr the Scheleger and Turner, 1963, method was done on the coat not shaved (SRcoat). The sweating rate was measured in the afternoon (from 2 P.M.), after 30 minutes of direct sunlight, on April. On May, the animals remained 60 minutes in direct sunlight because this day was colder. The experimental design was a non-probability sample restricted to the 10 available animals. Data from the steers sweating rate were analyzed using the General linear models of the SPSS® statistical package (version 12.0) using SRskin as dependent variable and breed and sampling date as independent

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. II. Rectal temperature and respiratory frequency / Resistência ao carrapato e tolerância ao calor em bovinos. II. temperatura retal e frequencia respiratória

The heat and Rhipicephalus microplus tick infestation are limiting factors to the livestock production in the tropics. Therefore, in a tropical sustainable livestock, cattle should be tick resistant and heat tolerant. The relationship between the Rhipicephalus (Boophilus) microplus tick infestation and heat characteristics like rectal temperature and respiratory frequency was studied in 6 Nellore and 4 Holstein, seven-month-old steers. They were submitted to an artificial infestation (a.i.) with 10,000 larvae (Holstein) and 20,000 larvae (Nellore) of Rhipicephalus (Boophilus) microplus tick in 16/Apr/2011. Females ticks bigger than 4.0 mm were counted in the left side from day 19 to 27 after the artificial infestation. The infestation rate was calculated by summing and multiplying by two the number of ticks counted, assuming that females are half of infesting larvae (5,000 for Holstein and 10,000 for Nellore). In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH), weighing the egg mass of each female fourteen days after. The rectal temperature (RT, measured by a digital thermometer in the animals rectum) and respiratory frequency (RF, respiratory movements per minute) were measured on days 14/Apr (2 days before the a.i.) and on day 05/May (19 days after the a.i.). The RT and RF were m

O artigo não apresenta resumo em português.

Tick resistance and heat tolerance characteristics in cattle. I. Hair length and coat thickness / Resistência ao carrapato e tolerância ao calor em bovinos. I. Comprimento e espessura do pelame

To be heat adapted and Rhipicephalus (Boophilus) microplus tick resistant are important characteristics for cattle in the Brazilian sustainable livestock, because this ectoparasite causes serious harm to the health of susceptible animals and, in the tropics, not heat adapted cattle have poor performance. Besides, the control of this tick is increasingly difficult due to drug resistance. Relationship between tick infestation and heat tolerance traits, as the hair length and coat thickness, are important because animals with long hair are easily identifiable, helping in the disposal of the least adapted cattle. In order to infer the relationship between tick infestation and fur characteristics, 6 Nellore and 4 Black and White Holstein steers, with about seven months old, underwent an artificial infestation (with 10,000 larvae on the Holstein, and 20,000 larvae on the Nellore) in 16/April/2011. In days 20, 23 and 24 post-infestation, the bigger 10 females ticks found throughout the body were weighed and their egg mass weighed 14 days later. Hair length, HL (collected with pliers specially adapted for this purpose, and measured the 10 longest hair) and the coat thickness, CT (measured with a metal ruler inserted perpendicular to the skin) were evaluated in the middle of the shoulder on 11/April (5 days before artificial tick infestation) and on 12/May (26 days after artificial tick

O artigo não apresenta resumo em português.

Filiform papilla of holsteins tongue and its relation with the Rhipicephalus microplus tick resistance / Papila filiforme da língua de novilhas holandesas e sua relação com a resistência ao carrapato Rhipicephalus microplus

Several studies describe anatomical, morphological and histological analysis of domestic and wild animals tongue. The tongue is an extendable muscular organ that performs gripping, chewing, and swallowing food actions and executes tasting and mechanical body self-cleaning functions (grooming). The distribution of these tongue characteristics may vary, according to different species, but studies made with different animals classes reveal the filiform papilla acting in mechanical body cleaning function. In order to evaluate these mechanical functions, especially the self-cleaning one, we proposed to investigate filiform papillae length or its base dimensions would be related to the heifers resistance to Rhipicephalus microplus tick. Biopsies were performed in eight (8) Holstein heifers tongues, with a 6 mm diameter punch, in the anterior third of tongues, at the distance of 3 cm from its tip. The animals were anesthetized with xylazine hydrochloride 2%, a sedative, analgesic and muscle relaxant and received local anesthetic, hydrochloride 2.0 g lidocaine. After tissue removal, the local lesions received an ointment of triamcinolone acetonide, 1.0 mg g-1. The Holstein heifers were one year and half old and naturally infested with ticks in a paddock situated at Instituto de Zootecnia. We monitored their natural infestation by counting females ticks, greater than 4.5 mm, presents

O artigo não apresenta resumo em português.